Newsletter No. 10, Spring 2003 - USGS · Page 2 MARGINS Newsletter No. 10, Spring 2003 ment...

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In This Issue:

Published bi-annually by the

MARGINS OfficeLamont-Doherty Earth Observatory

of Columbia University

61 Route 9W, P.O. Box 1000

Palisades, NY 10964-8000

USA

Science Article

Costa Rica margin, ODP Leg 205

Editorial

Marine Mammals, Event Response

Data Management Article

Efficiency, Quality, Integration

Workshop reports

SEIZE 2003 Theoretical Institute

Science & Policy Updates

Marine Mammals & Air Guns

EUROMARGINS on its way

Funded MARGINS Programs 2003

MARGINS Post-docs

Steering Committee Highlights

Office Update Website update

Contact Information

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The character of the incoming plate sub-ducting at convergent margins and theprocesses affecting it as it passes belowthe shallow forearc may play a major rolein the nature and extent of hazardousinterplate seismicity as well as the mag-nitude of volcanism and the chemistry oflavas produced in the overlying volcanicarc. The fate of incoming sediments andocean crust, and of their associatedvolatiles, as they pass through the shal-low levels of a subduction zone (0-50 kmdepth) has profound effects on the behav-ior of the seismogenic zone, which pro-duces most of the world’s destructiveearthquakes and tsunamis. Fluid pressureand sediment porosity influence faultlocalization, deformation style andstrength, and may control the updip limitof the seismogenic zone (e.g., Scholz,1998; Moore and Saffer, 2001). Fluidswithin both fault zones and sedimentsunderthrust at the trench affect earlystructural development and are a keyagent in transport of chemical species.The mineralogy and chemistry of anysubducted sediments and their dehydra-tion reactions during subduction may af-fect the physical properties of the deepersubduction interface and, hence, downdiplimits of the seismogenic zone.

The escape of fluids to the surfacefrom the downgoing plate at depth maysupport a deep biosphere, contributesmethane and higher hydrocarbons for gashydrate formation, affects seawaterchemistry for selected elements, and isintimately linked to deformation, fault-ing, and the evolution of the décollement.The distillation and loss of some volatilesand fluid-soluble elements from the shal-low slab record reactions and processeswithin the seismogenic zone. They also

ODP Leg 205 Explores Active Fluid Flow Across

the Costa Rica Convergent Margin to Investigate

the Subducton Factory and Seismogenic Zone

LEG 205 SHIPBOARD SCIENTIFIC PARTYJulie Morris*, Heinrich Villinger, Adam Klaus, Dawn Cardace, Peter Clift, ValerieChavagnac, Toshio Hisamitsu, Miriam Kastner, Marion Pfender, Demian Saffer,

Cara Santelli, Burkhard Schramm, Liz Screaton, Evan Solomon, Michael Strasser

*Corresponding Author:Department of Earth and Planetary Sciences, Washington University in St. Louis,Campus Box 1169, One Brookings Drive, Saint Louis, MO 63130, USA

play a central role in the supply of re-sidual volatiles to the deeper Earth andchange the composition of the slab de-livered to the depths of magmatism be-neath volcanic arcs. Processes operatingin the shallow subduction zone thus af-fect the way the slab contributes to con-tinent-building magmatism, explosivevolcanism, ore formation and, ultimately,the evolution of the mantle through time.The subduction signature recorded in thechemistry of arc volcanics constrains thenature and sometimes the volume of thesediments transported through theseismogenic zone to the depths ofmagmatism. The arc thus acts as a flowmonitor for the transport of sediments todepths greater than those that can bedrilled or imaged seismically.

Sailing from Acapulco Mexico onSeptember 13, 2002, a team of interna-tional scientists joined co-chiefs HeinerVillinger (University of Bremen, Ger-many) and Julie Morris (WashingtonUniversity USA) and Ocean Drilling Pro-gram (ODP) Staff Scientist Adam Klausaboard the JOIDES Resolution (See Fig.1). Leg 205 was intended to investigateactive fluid flow in both the subductingplate and along the decollement zone off-shore of the Nicoya peninsula (see Fig.2). A primary goal of the cruise was toinstall long term sea floor observatories(CORK-IIs) to monitor and sample fluidflow for a period of ~5years.

Central America is a focus area forthe U.S. MARGINS program, and is alsounder intensive study by German scien-tists. It is an important area for studiesrelated to MARGINS Seismogenic Zoneand Subduction Factory initiatives forseveral reasons. As one of the few mod-ern arcs subducting a carbonate-rich sedi-

MARGINS Newsletter No. 10, Spring 2003

ment section, Central America permitsstudy of CO

2 recycling through a subduc-

tion zone.A large body of work also shows that

there are differences in seismicity and arcmagmatism along the length of the Cen-tral American margin that appear to cor-relate with changing sediment dynamicsalong strike. The Nicoya section of theCosta Rica margin appears to have Mw= 7 or greater earthquakes at a 40- to 50-year recurrence interval, with the lastsuch event in 1950 (Guendel, 1986). Cou-pling between the downgoing and over-riding plates is estimated from Global Po-sitioning System (GPS) data to be 40%-60% (T. Dixon, pers. comm., 2001) andappears to start ~15 km arcward of thetrench. Nicaragua is characterized by agreater frequency of magnitude 7 orlarger earthquakes, including the 1992tsunamogenic earthquake. In detail, theupdip limit of seismicity appears to be at~ 20 km depth north of the fracture zonetrace shown in Figure 2 and at ~10 kmdepth to the south (Newman et al., 2002).

There are also significant changes involcanism between Nicaragua and CostaRica, with an offset in the volcanic chainjust north of the northernmost Nicoyapeninsula (Fig. 2). In Nicaragua, the arc-trench gap is 180-190 km and the volca-noes lie approximately 180-200 kmabove the Waditi-Benioff Zone of thedowngoing slab. In Costa Rica, the arc-

trench gap narrows to ~165 km and theseismic zone is approximately 120-130km below the volcanoes (Protti et al.,1994). Nicaraguan volcanoes tend to besmaller than those of Costa Rica; whenaveraged over the last 100-130 ka,

magma production rates (com-piled in Patino et al., 2000) aremuch lower in Nicaragua thanCosta Rica being ~14 and 44km3/km arc length per millionyears, respectively. In the chem-istry of the arc volcanics, 10Bedata, radiogenic isotopes, andtrace element studies of Nica-ragua lavas (Reagan et al.,1994; Patino et al., 2000) sug-gest that the entire sedimentsection is subducting to thedepths of magma generation,producing in the lavas a strongsignature from the hemipelagicsediments at the top of the in-coming sediment section. In

contrast, the Costa Rican lavas have amuch lesser sediment signature, littlecontribution from the uppermost hemi-pelagic sediments of the incoming plate,and a proportionally larger contributionfrom the basal carbonate section.

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Leg 205(Fig. 3)

M i d d l eNicaragua

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Nicaragua Volcanic Front

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Figure 1. Photograph of shipboardscience party for Leg 205 infront of re-entry cone.Standing rear: MatthiasHaeckel, Paola Vannucchi.Standing Center: EvanSolomon, Marion Pfender,Burkhard Schramm, LizScreaton, Valerie Chav-agnac, Julie Morris, Dem-ian Saffer, Heiner Villinger.Kneeling: Michael Strasser,Dawn Cardace, Peter Clift,Cara Santelli, Moe KyawThu, Toshio Hisamitsu.Seated front: Adam Klaus.Not shown: Miriam Kast-ner.

Figure 2. Leg 205 Costa Rica drilling area (red box) and isochrons derived from seafloormagnetic anomalies (Barckhausen et al., 2001). Numbers indicate crustal age inmillion years. Tectonic boundaries, convergence direction and rate (arrow; de Metset al., 1990) as well as arc volcanoes (triangles) are shown. Note offset in volcanicarc between Nicaragua and Costa Rica. FS = Fisher Seamount, QSC = QuesadaSharp Contortion.

Science Article


Science objectives for Leg 205 (seeFig. 3) translated to two primary foci,both related to seismogenic zone and sub-duction factory questions. The first wasto characterize and monitor two of thethree hydrologic systems inferred fromLeg 170 drilling (Kimura, Silver et al.,1996): in the igneous section of the sub-ducting oceanic plate and across thedecollement zone. The second was todetermine the igneous and alteration his-tory of the uppermost part of the downgoing plate at reference Site 1253, alongwith the inferred distribution of fracturepermeability in the core and borehole.During Leg 205, we carried out targetedcoring and logging at the reference Site1253 on the incoming oceanic plate, andinstalled a CORK-II. Inboard of the de-formation front, we cored a thrust fault

within the prism and the decollementzone at Site 1254. Attempts to install aCORK II at this site failed, due to a combi-nation of operational problems and hole con-ditions. A CORK-II was successfully in-stalled in the decollement zone at Site 1255,0.4 km inboard of the deformation front.

In the vicinity of Site 1253, both heatflow data and the chemistry of porefluidssampled from deep sediments suggestthat there is extensive flow of cool fluidsin the basement of the incoming oceaniccrust, created at the East Pacific Rise at~ 24Ma. Heat flow in the Leg 205 vicin-ity (Langseth and Silver, 1996, TICO-FLUX I and II, METEOR Cruise 54-2)averages about 30 mW/m2, about 1/3 ofthe expected value from lithosphericcooling (Stein and Stein, 1992) and in-crease to an average value of about 110mW/m2 south of the Fracture Zone Trace(See Fig 1). Plates north and south of theFZT have approximately the same age soone would expect them to show similaraverage heat flow. That the crust northof the FZT is significantly cooler impliesthat a substantial amount of its heat isprobably being removed by fluid circu-lation within the crust. The more recentcruises show a complex distribution oflocal heat flow highs and lows withineach region, which provide informationfor eventual detailed modeling of theflow systems and their driving forces.

Pore fluid chemical profiles deter-mined shipboard also suggest extensivefluid flow at depth beneath reference Site1253 on the incoming plate. Variationsin Ca, Sr, Li, H

4SiO

4 and SO

4 concentra-

tions in porefluids sampled from calcare-ous sediments at depth were observed atSite 1253. In all cases, concentrations in

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Figure 3. Bathymetric map of the Leg 205 drilling area showing Leg 205 (Sites 1253-1255)and 170 (Sites 1039-1043) drill sites. Location of seismic lines are shown by thered (BGR-99-44; C. Reichert and C. Ranero, pers. comm., 2001) and white (CR-20; Shipley et al., 1992) lines. Numbers along the BGR 99-44 seismic line areshotpoints. The white arrow gives the convergence direction and rate (88 mm/yr;de Mets et al., 1990). Location of map is shown in Fig. 2; bathymetric contours arein meters.

Figure 4. CORK HEAD. The “CORK” headis the last piece to be attachedabove the screen, packer, andcasing. The head contains thepressure sensors and data loggers.It also has valves and a data portthat can be operated by a sub-mersible or remotely operatedvehicle. The “CORK” head will fitinto the reentry cone on the sea-floor to seal, or “cork”, the bore-hole; the sensors will be down inthe sealed hole beneath it.


basal sediments change towards valuestypical of modern seawater (Morris,Villinger et al., 2003). Similar patternsfor Leg 170 samples are also observed;87Sr/86Sr isotopic compositions for Leg170 samples (not yet available for Leg205) deviate from values expected fromthe paleo-seawater curve and trend to-wards modern seawater compositions atdepth (Silver et al., 2000).

At Site 1253 on the incoming plate,we cored 230 meters, including ~170 mwithin two igneous units, where the up-per is a 30 m thick sill with sedimentsabove and below. We also logged up to150 m, primarily in the lower igneoussection, and installed a CORK II long-term seafloor observatory. The lower ig-neous unit may be an exceptionally thicksill composed of multiple intrusions, ora series of often thick and slowly cooledlava flows of oceanic crust created at theEast Pacific Rise, similar to those en-countered on ODP Leg 206 (Teagle, Wil-son et al., 2003). Core descriptionsshowed that the section is more exten-sively altered and fractured below about510-513 mbsf, while logging results con-firm greater fracturing imaged in theborehole walls.

A CORK II was installed at Site 1253,with temperature probes and osmoticfluid and gas samplers at 497-504 mbsfand also at 512-519 mbsf (See Fig. 4 and5, and Jannasch et al., 2003). Pressuremonitoring is within the upper Osmo-Sampler zone, and above the packer at~453 mbsf. The osmotic samplers(Teflon tubing for fluid analysis and cop-per tubing for gas analysis) use osmoticmembrane pumps to recover boreholefluids that are pushed progressively fur-ther along the sampling coils with time.Submersible dives in 2004 (to be led byMiriam Kastner, Earl Davis and HeinerVillinger) will recover the osmotic sam-plers and install a new set designed tooperate for ~4 years. The dives will alsorecover and replace temperature loggersand download pressure data from theCORKs. An Alvin dive in November2003, by Keir Becker, showed the CORKinstallation to be operational. Ideally,

upon recovery in 2004, the pressure andtemperature loggers will show boreholerecovery from drilling perturbations andthe fluid and gas compositions will showtransition to seawater compositionsmodified by water:rock interactions.

Inboard of the deformation front, drill-ing at Site 1254 in the prism coredthrough a thrust fault zone at ~197-219mbsf and the decollement zone at 338-365 mbsf. Despite drilling disturbance itis possible to see that deformation, par-

ticularly brecciation and brittle shearing,generally increase downward in bothzones, but with concentration of shearalong specific horizons. Anomalouslyhigh concentrations of thermogenic hy-drocarbons (including ethane, pentaneand hexane) in the gases and sediments,and unique pore water chemistry (el-evated Li and Ca, decreased K) are seenwithin both fault zones, indicating advec-tion of exotic fluids, possibly along sandyhorizons showing brittle fracture within

upper osmosampler

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sinker bar

CORK-II well head

CORK-II well head top: 4381.12 (4370.22 mbsl)

reentry cone

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seafloor: 4387.2 mbrf (4376.3 mbsl)

reentry cone top: 4384.7 mbrf (4373.80 mbsl)

16" casing shoe: 4431.0 mbrf (43.8 mbsf)

10-3/4" casing shoe: 4800.1 mbrf (412.9 mbsf)

packer top: 4856.06 mbrf (468.86 mbsf)

packer element: 4860.13 mbrf (472.93 mbsf)

packer bottom: 4864.58 mbrf (477.38 mbsf)

screen top: 4880.73 mbrf (493.53 mbsf)

screen: 4887.57 mbrf (500.37 mbsf)

screen bottom: 4892.85 mbrf (505.65 mbsf)

lower osmosampler 4903.0 mbrf (515.8 mbsf)

sinker bar bottom: 4908.0 mbrf (520.8 mbsf)

1.42 m

4-1/2" casing string top: 4388.6 mbrf (1.42 mbsf)

lower 4-1/2" casing string length

bottom 14-3/4" hole: 4810.2 mbrf (423.0 mbsf)

upper screen: 4840.00 mbrf (452.80 mbsf)

bottom 9-7/8" Hole: 4987.1 mbrf (600.0 mbsf)

16.15 m

screen

packer

Figure 5. Fig. 5) Schematic for Hole 1253A CORK-II installation showing subseafloor depthsfor osmotic water samplers, screens, packers, and casing strings. This figure is notto scale.

Science Article


the fault zones. The porefluid geochem-istry suggests that some fraction of thefluids derived from regions with tempera-tures >90-100°C, or possibly higher. Thebase of the décollement lies within theuppermost part of the underthrust sectionat Site 1254, as opposed to between theprism and underthrust sediment at Leg170 Site 1040, 50 m away. Several at-tempts were made to install a CORK-IIat Site 1254, twice into the decollementzone, and once into the shallower thrustfault. All failed due to a combination ofoperational difficulties and hole condi-tions.

At prism Site 1255 ~0.4 km inboardof the deformation front, we carried outvery limited coring to identify thedecollement zone and installed a CORK-

II into the plate boundary fault. The baseof the decollement was placed at 144mbsf and corresponds to the lithologicboundary between prism and underthrustsediments. The chemical signature ofdeeply sourced fluids was observed justabove the decollement, but is weaker thanat Site 1254. The CORK-II was installedsuccessfully, with the packer centered at129 mbsf and the Osmo-Sampler cen-tered at 140 mbsf, along with a tempera-ture logger and pressure monitoringscreen. This deployment also included anOsmo-flow meter located below theOsmo-Samplers for fluids and gases(Jannasch et al., 2003). Injecting iodate,Rb and Cs at a constant rate into the in-coming fluids, which are also sampledosmotically, their concentrations in the

analyzed fluids will constrain flow rates.With flow rates and fluid compositions,it should be possible to determine fluxesof elements such as B, Li, U, K, Ca outof the downgoing plate. With a centralinjection port surrounded by four sam-pling ports, it may also be possible toelicit information about flow directions.This installation was also visited by Alvinin November 2002 and is fully opera-tional.

For additional information, the readeris referred to the Preliminary Report forLeg 205, currently available on the ODPwebsite: www-odp.tamu.edu/publica-tions/prelim/205_prel/205toc.html.

References:

Guendel, F., 1986. Seismotectonics of Costa Rica: an analytical view of the southern terminus ofthe Middle American Trench [Ph.D. thesis]Univ. of California, Santa Cruz.

Jannasch, H., Davis, E., Kastner, M., Morris, J., Pettigrew, T., Plant, J., Solomon, E., Villinger, H., Wheat, C., 2003. CORK II: Long-TermMonitoring of Fluid Chemistry and Hydrology in Instrumented Boreholes at the Costa Rica Subduction Zone. In press IR Volume205.

Kimura, G., Silver, E.A., Blum, P., et al., Proceedings of the Ocean Drilling Program, Initial Reports, 170 (1997), College Station, TX.Langseth, M.G., and Silver, E.A., 1996. The Nicoya convergent margin: a region of exceptionally low heat flow. Geophys. Res. Lett., 23:891-

894.Moore, J.C., and Saffer, D.M., 2001. Updip limit of the seismogenic zone beneath the accretionary prism of southwest Japan: an effect of

diagenetic to low-grade metamorphic processes and increasing effective stress. Geology, 29:183-186.Morris J., Villinger H., Klaus A. et al.,. Proceedings of the Ocean Drilling Program, Initial Reports, 205 (2003), College Station, TX, in press.Newman, A.V., Schwartz, S.Y., Gonzalez, V., DeShon, H.R., Protti, J.M., Dorman, L.M., 2002. Along-strike variability in the seismogenic

zone below Nicoya Peninsula, Costa Rica. Geophys. Res. Lett., 10.10292002GL015409.Patino, L.C., Carr, M.J., and Feigenson, M.D., 2000. Local and regional variations in Central American arc lavas controlled by variations in

subducted sediment input. Contrib. Mineral. Petrol., 138:265-283Protti M., Guendel, F., and McNally, K., 1994. The geometry of the Wadati-Benioff zne under southern Central America and its tectonic

significance: results from a high-resolution local seismographic network. Phys. Earth Planet. Inter., 84:271-287.Reagan, M., Morris, J., Herrstrom, E., and Murrell, M., 1994. Uranium series and beryllium isotopic evidence for an extended history of

subduction modification of the mantle below Nicaragua. Geochim. Cosmochim. Acta, 58:4199-4212.Scholz, C.H., 1998. Earthquakes and friction laws. Nature, 391:37-42.Silver, E.A., Kastner, M., Fisher, A.T., Morris, J.D., McIntosh, K.D., and Saffer, D.M., 2000. Fluid flow paths in the Middle America Trench

and Costa Rica margin. Geology, 28:679-682.Stein, C.A., and Stein, S., 1992. A model for the global variation in oceanic depth and heat flow with lithospheric age. Nature, 359:123-129.Teagle, D, Wilson D and Miller, J. et al., 2003. ., Proceedings of the Ocean Drilling Program, Initial Reports, 206, College Station, TX. In

press.


It seems only a short time ago that our“baptism by fire” was upon us as we fran-tically organized the Puerto Vallarta andSharm el Sheik workshops while assem-bling the Lamont MARGINS Office.That was 3 years ago and on the 9 May,2003, we bade farewell to Joan Basheras she and her husband Reid prepared tomove to Geneva, Switzerland. OlafSvenningsen and I (on behalf of the Steer-ing Committee) wish them well and thankJoan for her good kiwi wit and hard workfor the MARGINS community over thelast 3 years — it was much appreciated.The dismantling of the Lamont MAR-GINS Office has begun.

The Fall-Spring period of 2002-2003has been extremely busy for the MAR-GINS Office, with the running of a num-ber of important workshops and theoreti-cal institutes and preparing a series offiles and documents to help with the tran-sition of the MARGINS Office from NewYork to Saint Louis. The transition willoccur over a three-month period betweenJuly and September, with the Saint Louisoffice taking full control of the MAR-GINS Office on the 1 October, 2003.Efforts are also underway to publish allof the revised, revamped, and updatedscience plans. Although the science plansare clearly dynamic documents, NSFconsiders it important to publish the thesedocuments, both to define the present-state and successes of each initiative, butalso to provide documents for internalNSF purposes and funding issues.

I would also like to thank ChuckFisher and his RIDGE 2000 staff (LizGoehring, Sharon Givens, and PattyNordstrom) for their invitation and hos-pitality during the recent R2K steeringcommittee meeting in Whistler, Canada,17-18 April, 2003. The task was to givean overview of the MARGINS program,discuss the procedures of how the MAR-GINS community selected focus sites,and the database aspirations of the MAR-

GINS program. Given the significantoverlap between MARGINS and RIDGEdatabase requirements, such a meeting isvery important in opening dialogue andexploring common links and goals betweenthe two programs.

The MARGINS Budget

The FY03 budget for MARGINS was$6.15M and while this number is a slightincrease compared to last year’s budget,the growth of the MARGINS budget re-mains slow and out of proportion com-pared to the cost of the excellent sciencebeing proposed. The situation will be ex-acerbated during FY04 as RCL-northernRed Sea and S2S-Waipaoa compete forfunds, along with the other focus sites,as they attempt to generate the necessarygeological and geophysical frameworksfor their subsequent research. NSF-EARhas restated its goal to be an equal fiscalpartner in the MARGINS program andhopefully with their new injection offunds this year, their goal may be real-ized in 2003-2004. An extra $0.75M-1Minput to the annual MARGINS budgetwould be a very welcomed addition. Thepresent proposal success ratio withinMARGINS in the last round was 40%,with proposals being funded in all initia-tives. I am very happy and proud to an-nounce that proposals were funded in thenorthern Red Sea RCL focus site for thefirst time, a momentous event given theimmense political instabilities generatedby the Iraqi war and recent terrorist ac-tivity within Saudi Arabia. Congratula-tions to Gomaa Omar, Daniel Stockli, andRobert Reilinger.

A first major step of MARGINS to-wards education and outreach was estab-lished this year by the successful imple-mentation of the MARGINS post-doc-toral fellowship scheme. We are verypleased to announce the awarding of

three fellowships in our first year. De-tails of the proposed work and generalinformation about the successful appli-cants are presented later in this newslet-ter (page 19).

I would also like to take this opportu-nity to clarify the “rude awakening” ex-perienced during FY02, the first yearwhere MARGINS had significant ODP-related shipboard programs, when $1.4Mof our budget was spent on ship opera-tions as opposed to being dedicated toresearch activities. In general, University-National Oceanographic Laboratory Sys-tem (UNOLS) ship operations are paidfor by NSF-Ship Operations. Any pro-posal using a non-UNOLS ship, such asfor example, a small Australian or NewZealand vessel for coastal research, theship costs need to be included in the pro-posal budget. However, for those MAR-GINS proposals funded (or partly fund-ed) by NSF-ODP, then ship costs areborne directly (or proportionately) by theMARGINS program.

Marine Mammals and theMARGINS Program: An update

Following the shock to the marine scien-tific community over the court injunctionthat brought academic seismic work to anear halt late last year, there is particu-larly good news to report in terms of theissues involving the Marine MammalsProtection Act (MMPA), the R/V Ewing,and the lawsuit between the NationalScience Foundation and the Center forBiological Diversity (CBD). In short, thelawsuit has been settled, at least for theshort term, and is the subject of a detailedarticle by Jim Yoder in this issue of theMARGINS newsletter (page 14). Thesettlement will allow NSF-funded re-searchers to continue to use seismicsources aboard the R/V Ewing, the keyUS research vessel for the field of ma-

From the Chairman’s Desk: Spring 2003Garry D. Karner

Lamont-Doherty Earth Observatory, 61 Route 9W, Palisades, New York 10964, USA; E-mail: [email protected]

Editorial


rine seismic research. This is very wel-comed news for the MARGINS program.

Event Response Plans

The MARGINS program, having made acommitment to studying active systems,has always recognized the importance ofhaving a strategy for event response, sinceeven “active” systems may be only inter-mittently active. The earth sciences com-munity had contingency plans in ready torespond to volcanic eruptions and earth-quakes. Other events relevant to MAR-GINS for which response strategies arerequired include major storms that modifythe sedimentary environment on continen-tal shelves, and floods that alter the shapeof rivers, deltas, and landforms. However,to date, such natural events, and thus eventresponses, had not presented themselveswithin the timeframe of either the Hawaiior Lamont offices — but that was all aboutto change!!

Anatahan volcano erupted at about9:00 GMT on May 10, 2003. The erup-tion was observed from a small ship de-ploying seismographs for the MARGINSMariana Subduction Factory project(Doug Wiens, Chief Scientist). A heli-

copter sent out by the CNMI emergencymanagement office reported an ash cloudreaching to about 40,000 ft. The eruptioncontinued on May 12. The island wasvisited by the SubFac team on May 6 andthere were no indications of an eruptionat that time.

Based on budget information fromDoug Wiens and recommendations fromthe SubFac community, the MARGINS Of-fice organized an event response plan forvolcanologists Toby Fischer (UNM) andDavid Hilton (UCSD) and geophysicistsAllan Sauter and Juan Camacho to visitAnatahan to deploy a telemetered seismom-eter, repair the SubFac project seismom-eter, and collect ash, flows, pumice, and

Figure 1. The Anatahan eruption, a 40,000' ash cloud, on May 10, 2003.Photo courtesy of Allan W. Sauter.

Figure 2. Our intrepid SubFac researchers.Front left to right, Toby Fischer,David Hilton, and Juan Camacho.

bombs from the Anatahan eruption.The telemetering of seismic data to

the ship was imperative and essential toconducting on-island operations in addi-tion to determine the eruptive state of theisland. From the ship, the group set upthe COSPEC instrument and conducteda traverse through the plume. The tele-scope was oriented vertically and the shipmade a north-to-south transect throughthe volcanic plume at a distance of about1.5 km from shore. Once the Anatahansamples arrive on the US mainland, anintensive analysis program has been or-ganized by Jim Gill, Julie Morris andTerry Plank. An AGU Fall 2003 specialsession is being arranged to present thevolcanologic, geochemical, and petro-logic analyses of the Anatahan samplesand the tectonic implications of the seis-mic data collected during the eruptions.

The MARGINS Steering Committee

Two people rotated off the committeeduring the Fall, 2002 semester. The com-mittee would like to take this opportu-nity to thank Marc Hirschman and JoannStock for their unselfish contribution oftime and effort to the steering committeeand the Earth Scientific community.Marc and Joann both provided soundjudgment and advice during the delibera-tion of a range of committee and com-munity issues, most importantly on thefellowship and data policy documents.The committee also recognizes the sig-nificant contributions Marc and Joannmade to their communities (SubFac andRCL, respectively) by being co-authorson a number of workshop proposals andtaking the lead on contributing and re-vising their respective science plans. Weare indebted to both of them for theiruntiring efforts.


Summary

Data management is more than a safe-keeping and then retrieval of the originaldata. The strongest benefits from manage-ment of geologic data will accrue to MAR-GINS when the many separate datasetscan be combined and used to create inte-grated datasets at a wide range of spatialtemporal scales, for purposes that stretchacross disciplines, and that are convenientfor researchers to use. The data need tobe usable, not just available.

The Idea of Integration

The data collection methods which areused by investigators in the marine geo-logical science programs of MARGINSare diverse. They have to be, because theyinvestigate the range of known geologicprocesses in many different settings, forgeologic materials from liquid to softsediment to rock, in biogenic/volcanic/terrigenous settings, and for a range ofultimate project goals. Many differentcollection devices have to be used, andmany descriptive and measurement tech-nologies are employed. But this diversitypresents challenges for the managementof the data; not so much in the data stor-age and retrieval (which is conceptuallystraightforward in spite of attribute di-versity), but in the issue of bringing thisdata into a form where integrated scien-tific products can be made. By integratedscience products, I mean datasets that canbe merged without intensive manipula-tion, large and useful information setsformed by combining smaller datasets,and visualizations / grids that are readilyimportable into applications like GIS.

Integration of data sets is a prime rea-son why we wish to have data manage-ment systems. (i) It allows us to mergedatasets for a greater common benefit.

Data from many small campaigns be-comes useable at spatial scales, timeranges and resolutions different fromthose of the original studies - a goal whichis key to the earth-system research goalsof programs like MARGINS. And thedata can be ‘re-purposed’.

(ii) Data which is integrated in oneconvenient-to-use form, can also help in-dividual studies - for instance to developsampling strategies, provide the environ-mental context of a local experiment, andenable the validation of models.

Integration of data is also a key toNSF’s important goals of encouragingcooperative and inter-disciplinary science(NSF 2002), growing and exploiting syn-ergies in research, and forwarding resultsto the community at large — especiallyto education. European science plannersexpress the need to make integrated dataavailable as a “provision of essential ser-vices”, like a nourishment of science orsupply of water and electricity to a town.In both views geologic data from MAR-GINS ought to be freely and convenientlyavailable to scientists of sister disciplines(geophysicists, ecologists, biochemists,oceanographers) and also to communityeducators and decision makers.

The State of Play

Unfortunately, geological data has re-sisted digital integration while other sci-ences have streaked ahead in joining theirresults to global scale models and com-munity debates about the environment.The Smith and Sandwell (1997) bathym-etry compilation brought an earth sci-ences dataset into use in a multitude ofother fields, (e.g., into biodiversityinformatics; OBIS, Ocean BiogeographicInformation System, www.iobis.org/).The World Ocean Atlas (Levitus et al.1994) is another integration that has im-

mense application through science. Boththese, however, were built largely of ma-chine derived, relatively well disciplineddata — like data from bank ATM’s.

By contrast, scientists still face adauntingly complex and time consumingtask just to merge the geologic datasetsfrom successive expeditions in one re-gion. Digital data integrations of say, de-scriptive and measured observations, oflaboratory and probe device datasets, oracross neighbouring terrigenous and car-bonate systems are hardly ever made —even though MARGINS is intended todiscover and address big-scale, long-ep-och factors of the earth’s geobiosphere.

How difficult it is for researchers tocombine MARGINS type data, let aloneintegrate it, can be appreciated from vis-iting present online databases (e.g., AWIand MARUM ‘Pangaea’, www.pan-gaea.de/, Dittert et al. 2002; NGDC‘World Data Center for Marine Geology& Geophysics’, www.ngdc .noaa.gov/mgg/geology/geology.html; LDEO‘PETdb’, petdb.ldeo.columbia .edu/petdb/, Haxby 2002). These structureshave commendable presentation, contentof data, and software stability, but itwould be very difficult for researchers togenerate an integrated regional datasetfrom them for organic carbon values,sedimentation rates, or even grainsizes.High levels of skill in data manipulationwould be required, levels which mostresearch geoscientists do not have. Insome systems data is rendered variouslyin columns of XY Z A, Z {XY} A, ZA{XY}, Z A1{XY} A2{XY} and otherarrangements (where: XY is site location,Z subottom depth, A attribute, {} meansimplicit or held in metadata). There isvariety also in the row arrangements, andvital details — like descriptions of thematerials under analysis — are often heldin a miscellany of metadata. To down-load and combine such data, investiga-

Data Management of MARGINS Geologic Data, with Emphasis

on Efficiency, Quality Control and Data IntegrationChris Jenkins

INSTAAR, The University of Colorado, Boulder CO 80309-0450 USA; Email: [email protected]



tors will need to transpose tables, cut andsplice rows/columns, merge in data heldas metadata, sort on XY or Z and trans-form units. This will have to be donedataset by dataset, perhaps in each casewith a complex combination of manipu-lations. Systems with this design - whichmay have thousands of datasets on oneissue, like organic carbon - are not a greatadvance over a data warehouse wheredata in every conceivable form is storedand retrieved more-or-less as lodged bya multitude of independently-minded re-searchers.

Achieving Data Integration

Devising data management methods toovercome these problems and achievefull and rich integrations of geologic datais the focus of a long-term, multi-institu-tional project based at INSTAAR in the

University of Colorado but also involv-ing the USGS, NGDC and The Univer-sities of Kansas and Sydney (Australia).This new approach to geologic data firstperforms orthodox data management re-quirements in the sense of storage andretrieval: it produces standard relationaldatabase (RDB) structures of the origi-nal data. But it does this within a processthat also integrates the geologic datawhich then becomes ready-to-use in Geo-graphic Information Systems (GIS) plot-ted as maps and sections, in RDB, and inmany other applications. The process ismostly automated and has a range ofquality control tools built in to that auto-mation. Ready-to-use products include:large unified datasets to support statisti-cal and other analyses; graphical corelogs to superimpose on geophysical pro-files; and spatially gridded values or pa-rameters capable of being dynamicallyported as inputs to numerical models. The

system has accomplished detailed map-pings of the US (Williams et. al. 2003)and Australian EEZ’s, and holds nearly1 million attributed samples worldwide.A significant feature of the system is thatthe fundamental ‘raw’ data is held in aprimitive form, not in vendor-specificsoftware, but in an ASCII tree-structuredcore-log format. Since that layout is com-monplace in geologic data it is efficientfor data import, and is readable by hu-mans - a whole dataset at a time. The datais then brought into a relational databasestructure algorithmically. The efficiencyof this structure for data import with qual-ity control is extremely high. A key pointis that rather than data being manuallyentered into tables, which is costly andprone to human error, this system mini-mizes human intervention on contributeddatasets at import and can import in bulk.A second key point is that new datasetsare immediately ‘worked’ — testedagainst automated quality filters and theoutputs are made available immediatelyfor visual inspection by attribute and lo-cation, and in comparison to nearby andoverlapping datasets. Both the machineand human error detections are actedupon (corrected or flagged) in the basicdata and in the metadata which is helddirectly with the data to which it refers.

A Great Divide Bridged

Probably the greatest divide in geologi-cal data has been that between measurednumeric and descriptive word-based data.Whether we view ODP datasets orNOAA estuarine surveys, the bulk of datais still descriptive and word-based: graincounts, lithology, consolidation, odor,mesoscale structures, texture and fabric,etc. Word based data has many virtuesrelative to numeric, it is often more ac-curate (applies to whole of sample, not asmall laboratory aliquot), is independentof technique (e.g., spans whole range ofconsolidations, shear strength instru-ments measure in certain ranges), and forfacies is an extremely rich informationsource (e.g., biogenic components and

Figure 1. Interactive mapping of seafloor properties surrounding the Mississippi Delta - anintegrated data management product highly relevant to MARGINS programs,especially Source to Sink. The full colour version is online (Jenkins et al. 2002).This coverage integrates over 26 datasets into a product that may be used easily byresearchers and the public. The characteristics of marine sediments such as sandbars are visualized alongside onshore data layers that show land use, patterns ofsubsidence / flooding and geology.


cements). The criticism of word data be-ing more vague (less precise) than nu-merics is correct, but well proven mathe-matical techniques now exist to convertword data into numerics, using fuzzy settheory. This opens the way for splicingword based data in with numeric data -an exciting avenue for geological synthe-sis.

Although word-based data can be heldin relational databases and queried, it hasnot been possible (or at least very expen-sive) to have an algorithmic parser setup inside these commercial softwarepackages and applied to geologic datatypes with a geologic thesaurus. But wehave built an algorithm which works verywell on the primitive data, with accura-cies comparable to those of laboratorygrainsize measurement. This conclusionis based on calibrations using instances(samples) where numeric and word dataare available for the same attribute (e.g.,grainsize).

Data Mining

One of the great advantages of integrateddatabases is that fortuitous cases (likereplicate and related measurements) inthe bulk of data can be exploited to dis-

cover if there are internal relationshipsthat can be used to improve the informa-tion arising from a database. This is datamining, where we learn about the param-eter inter-relationships from helpful partsof the data sets, then apply inverse rela-tionships to bring them into conformance.(Note that query operations no matterhow complex, are not data mining.) Forexample, the moment, graphical (Inman,Folk and Ward) and engineering mea-sures of grainsize and sorting which havedivided geologic data can be reconciledin many cases - once relationships be-tween them are established.

Uncertainty is not often reported ingeologic data but is crucial if our resultsare to be taken up for decision making— in global change issues for instance.Data mining can also be used to find out,then attach uncertainty values to data.This may be done by comparing repli-cates or related values, as above, so thaterror analyses can be made. But evenmore importantly, integrated collectionsof quality controlled data provide excit-ing new opportunites for advanced sta-tistical analysis of whole sedimentologicsystems. Recently we obtained, in batch,measures of seafloor patchiness (spatialheterogeneity) across all zones of the US

Atlantic continental margin from coastalto abyssal. Those results have two appli-cations: (i) biologists now have a sourceof data from geosciences on marine habi-tat heterogeneity and which can be ap-plied in landscape ecology and studiesof adaptation, (ii) that geologists can at-tach quantitative spatial uncertainty val-ues to interpolated maps and griddingsas well as point measurements like cores.

Conclusion

The aim of data management is not onlyto safeguard public investment in data,but also to make that data available toaddress newly arising issues in scienceand society. The data must be integratedso that requests for geologic data can bemet with timely, comprehensive and co-ordinated responses. Storing and echo-ing geologic data from relational data-bases or other structures is certainly datamanagement, but the ‘cudos will reallyonly come when ready-to-use integratedproducts become publically available.

ReferencesDittert, N., Diepenbroek, M., Schlitzer, R., Sieger, R. & Wefer, G. 2002. WDC-MARE / PANGAEA: a convenient RDBMS partner with

MARGINS ? MARGINS Newsletter, 9 (Fall 2002), 16-21.Haxby, R., Arko, R., Carbotte, S. Chayes, D., O’Hara, S. & Ryan, R. MG&G Database Management Efforts at Lamont-Doherty Earth

Observatory. MARGINS Newsletter, 9 (Fall 2002), 16-21.Jenkins, C.J., Kettner, A.,Williams, S.J., Polloni, C.F., Reid, J.A., Currence, J.M. 2002. Northern Gulf of Mexico iSEABED. The University

of Colorado, Boulder, CO. [instaar.colorado.edu/~jenkinsc/dbseabed/usseabed/interactive/, November 2002].Levitus S. and Boyer, T. 1994. World Ocean Atlas 1994; Volume 4. U.S. Department of Commerce, Washington, D.C.NSF, 2002. NSF GPRA Strategic Plan, FY 2001 - 2006. [http://www.nsf.gov/pubs/2001/nsf0104/outcome.htm, 16 Feb 2003 download]Smith, W.H.F., and Sandwell, D.T. 1997. Global Sea Floor Topography from Satellite Altimetry and Ship Depth Soundings, Science, 277,

1956-62.Williams, S.J., Jenkins, C.J., Currence, J., Penland, S., Reid, J., Flocks, J., Kindinger, J., Poppe, L., Kulp, M., Manheim, F., Hampton, M.,

Polloni, C., Rowland, J. (accepted). New digital geologic maps of U.S. Continental Margins: Insights to Seafloor SedimentaryCharacter, Aggregate Resources and Processes. Coastal Sediments 03, 12pp.



Subduction zones generate the world’slargest and most destructive earthquakes,most of the world’s tsunamis, and mostof the world’s explosive volcanoes. Theyare also the sites where much of theworld’s population is concentrated (thecoastal zones) and, over geologic time,where most of the earth’s continentalcrust and mineral resources are gener-ated. NSF’s MARGINS program in-cludes the Seismogenic Zone Experiment(SEIZE) to study the shallow subductionplate interface that is locked and accu-mulates elastic strain, periodically re-leased in large or great earthquakes. Thescientific rationale for these studies wasoriginally outlined in the SEIZE scienceplan, posted on the MARGINS website(http://www.ldeo.columbia.edu/mar-gins), based on a workshop held in Ha-waii in 1997.

The MARGINS program officiallybegan in 1998, and has provided fund-ing for focused studies in the NankaiTrough and Central America, and else-where. A re-evaluation of key scienceissues related to SEIZE based on this andother research, and planning for future

studies, occured at the second MAR-GINS Theoretical Institute, held at Snow-bird, Utah, Match 16-21, 2003.

78 researchers from 10 countries at-tended the institute. Formal presentationscovered topics as diverse as the nature ofsubduction zone seismicity, seismic vsaseismic slip, fast vs slow rupture and tsu-nami earthquakes, geologic structure andphysical properties of seismogenic zones,the role of fluids, permeability and porefluid pressure, fluid chemis-try, the impact of sediment-starved vs sediment-cloggedtrenchs, the nature andmeaning of transient defor-mation events in subductionzones as recorded by GPS,and long term mountainbuilding.

There was ample time fordiscussion of the formal pre-sentations, and based on this,participants formulated a se-ries of critical questions forfuture research:

1) What controls the over-all distribution of seis-

MARGINS Theoretical Institute

The Seismogenic Zone Revisited — SEIZE 2003Tim Dixon1, Eli Silver2, Kevin Brown3, Kevin Furlong4, Seth Stein5, and Casey Moore2

1. RSMAS-MGG, University of Miami, 4600 Rickenbacker Cswy, Miami, FL 33149, E-mail: [email protected]. Earth Sciences, University of California Santa Cruz, Santa Cruz, CA 95064-1077

3. Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-02204. Dept. of Geosciences, Penn State University, 540 Deike Building, University Park, PA 16802

5. Dept. of Geological Sciences, Northwestern University, Evanston, IL 60208-2150

mic energy release during a subduc-tion zones earthquake (up, down, andalong strike). Is there one P-T-com-position condition that defines the on-set and down dip limits, or do thesevary with material properties andfault geometry in the subduction sys-tem?

2) What are asperities, and do they haveany long term significance? Whatcontrols the sometimes heteroge-

Figure 1. The Theoretical Institutewas held at the CliffLodge in CottonwoodCanyon, Snowbird, UT.The Wasatch MountainRange offered a specta-cular setting for themeeting.

Workshop Report

www.ldeo.columbia.edu/margins/SEIZE/ti03.html

Figure 2. The Theoretical Institute registration andinformation desk was professionally run by JoanBasher, here awaiting participants arrival togetherwith Brian Taylor, former MARGINS Chair.


neous distribution of locking patternson the plate interface and subsequentvariations of energy release on theseismic energy? Are asperities linkedby common physical processeswithin the fault region or governedby separate, unrelated phenomenon?Do they vary in time, and if so, overwhat time scale?

3) What controls the rate of propagationand slip rates of earthquakes and thedistribution of fast, slow, tsunami-genic, and silent earthquakes in timeand space?

4) What is the nature of temporalchanges in strain, fluid pressure andstress during the seismic cycle. Dothese change gradually during theseismic cycle or are there transientinterseismic phenomena that lead tostrain and energy release at varioustimes during the seismic cycle.

A book to be published by ColumbiaUniversity Press, consisting of review ar-ticles by leading scientists in the field andcovering key SEIZE-related topics, inpart based on presentations at the meet-ing, is planned for publication in 2004.

The MARGINS Office maintains ameeting website (URL below) with docu-ments and information pertaining to theSEIZE 2003 Theoretical Institute. Mostof the Powerpoint presentations from the

The SEIZE 2003 Theoretical Institute websitehttp://www.ldeo.columbia.edu/margins/SEIZE/ti03.html

Abstract titles from SEIZE 2003 (full texts available at website):

• Evolution of physical properties of the Nankai Trough plate-boundary thrust from the trench into the seismogenic zone inferredfrom 3-D seismic images (Nathan Bangs, Tom Shipley, Sean Gulick, and the Nankai 3-D seismic working group)

• Comparison of earthquake focal mechanisms and source processes between Nicoya and Osa Peninsulas, Costa Rica (Susan L. Bilek,Heather DeShon, Susan Y. Schwartz, and Andrew V. Newman)

• Issues and Opportunities in Seismic Reflection Imaging of the Sub-Continental Seismogenic Zone: Results of Reflection Modeling(Larry D. Brown, and Amy Kwiatkoswki)

• Coseismic, postseismic and interseismic deformation along the Kamchatka subduction zone (Bürgmann, R., Kogan, M.G., Levin,V.E., Scholz, C.H., King, R.W., and Steblov, G.M.)

• Measuring seafloor deformation across the Nazca/South America Plate convergence offshore Peru: Imaging the up-dip limit (C.David Chadwell, Edmondo Norabuena, John Hildebrand, Fred Spiess, Tim Dixon, Seth Stein)

• The evolution of the forearc Sandino basin: off Nicaragua sector of the Pacific convergent system (Central America) (K. McIntosh, I.Ahmed, C. Ranero, B. Taylor, P. Costa Pisani and E. Silver)

• Hydrodynamic Response of Subduction Zones to Seismic Activity: A Preliminary Study for the Costa Rica Margin (Paula A. Cutillo,Shemin Ge, and Elizabeth J. Screaton)

Figure 3. Scenes from the meeting (clockwise from upper left): Eli Silver opens a session fora full meeting room; Tim Dixon and Kevin Brown leading an afternoon discussionsession; Chris Marone starts his presentation with musings over suitable (andunsuitable) acronyms for the SEIZE focus initiative, and; intense discussions duringposter viewing.

talks, selected posters as PDF files, in-formation about the progress of the pub-lication of the book, a list of participants,and the abstract volume as a down-loadable PDF document are among theinformation posted on the website. Be-

low, the contents of the abstracts volumeis printed. Please refer to the website forthe most up-to-date information.

Workshop Report


• Comparisons between seismicity and fluid flow behavior along the western Costa Rica margin (Heather DeShon, Kevin Brown,Susan Schwartz, Mike Tryon, and LeRoy Dorman)

• Seismic Attenuation in the Subduction Zone of Costa Rica (LeRoy Dorman, Allan Sauter, Susan Schwartz, Heather Deshon, AndyNewman, Marino Protti, Sue Bilek, Ernst Flueh, Tim Dixon)

• The Seismogenic Zone Along the Alaska-Aleutian Trench (Jeff Freymueller, Chris Zweck, Steven Cohen, Sigrun Hreinsdottir, andHilary Fletcher)

• Along strike variability in the seismogenic zone and thermal models of subduction below the Nicoya Peninsula, Costa Rica (RobertN. Harris, Andrew V. Newman, and Kelin Wang)

• Secular, Transient and Periodic Crustal Movements in Japanese Subduction Zones, and Dynamics Underlying Them (Kosuke Heki)• Images of Seamount Subduction Beneath Nankai Margin (P. Henry, V. Martin, S. Lallemant, M. Noble, S. Kuramoto)• What We Know about Subduction Thrust Faults (R.D. Hyndman)• Variations in Basement Topography and Sediment Thickness on the Philippine Sea Plate Subducting Along the Nankai Trough (T.

Ike, J-O. Park, G.F. Moore, Y. Kaneda)• Deformation in granular aggregates: Implications for strength of porous rocks and shear within fault zones (Stephen L. Karner)• Comparative study on exhumed seismogenic faults and modern Nankai seismogenic megathrust (Gaku Kimura,, Arito Sakaguchi,

Kohtaro Ujiie, Airaro Kato, J-O Park, Yujin Kiramura, Eisei Ikesawa, Masayuki Matsumura and Yoshitaka Hashimoto)• Very focused expulsion of pore fluid along the western Nankai accretionary complex detected by closely-spaced heat flow measure-

ments (Masa Kinoshita, Shusaku Goto, Sean Gulick, Hitoshi Mikada, KR02-10 Shipboard Scientific Party)• Continental deformation in the Central Andes controlled by changing subduction parameters and geologic inheritance (Jonas Kley)• Partitioning of Seismogenic Strain in the Offshore Costa Rica Forearc (Jonathan C. Lewis and Susan Bilek)• Seismogenic Strain at the Costa Rica Convergent Margin (Jonathan C. Lewis and Allan Lopez )• Possible Forearc Sliver at the Lesser Antilles (Alberto M. López and Seth Stein)• Fault Friction and the Transition From Seismic to Aseismic Faulting (Chris Marone and Demian Saffer)• Characteristics of the Nicaragua convergent margin and their possible influence on seismicity and tsunami generation (Kirk McIn-

tosh, Imtiaz Ahmed, Eli Silver, Arnim Berhorst, Ernst Flueh, and Cesar Ranero)• Relationship of Fluids and Deformation at Seismogenic Depths: Structural Study of the Rodeo Cove Thrust Zone, Marin Head-

lands, California (Francesca Meneghini, J. Casey Moore)• Evolution of a ductile shear zone in the down-dip continuation of the seismogenic zone (Laurent G. J. Montési and Greg Hirth)• Factors Controlling the Frictional Strength of Sheet-Structure Minerals (Diane E. Moore and David A. Lockner)• Summary of ODP Leg 190 results in the Nankai Trough (G.F. Moore, Asahiko Taira, Adam Klaus)• Consolidation State and Overpressures Within the Underthrust Section, Nankai Accretionary Margin: Results of Uniaxial

Reconsolidation Experiments (Julia K. Morgan, and Maria V. S. Ask)• Splay Fault Branching Along the Nankai Subduction Zone (Jin-Oh Park, Tetsuro Tsuru, Shuichi Kodaira, and Yoshiyuki Kaneda)• Mapping the plates interface from the trench to the maximum depth of the Wadati-Benioff Zone under Costa Rica (Marino Protti,

Victor González, Susan Schwartz, Andy Newman, Heather DeShon and LeRoy Dorman)• Seismic imaging of the megathrust in Central-Southern Costa Rica (Cesar R. Ranero, Roland von Huene, Soenke Neben, Udo

Barckhausen)• Relative relocation of intermediate depth seismicity: A double Wadati-Benioff Zone below the Central Andes (Andreas Rietbrock,

and Felix Waldhauser)• Contrasts in veining and faulting across the aseismic to seismic transition in a sediment-rich accretionary complex (Christie Rowe,

Eric Thompson, and J. Casey Moore)• Geophysical and drilling evidence implies that a thick sandwich( 0.5->1.0 km) of sediment and detached continental margins

material separates the upper and lower plates; So what does this mean for forearc seismicity and expected deep drillingencounters? (David W. Scholl)

• Evaluation of the Updip Limit of the Seismogenic Zone in Central Costa Rica (S.Y. Schwartz, H.R. DeShon, and S.L. Bilek)• The Nankai Trough versus the Sagami Trough - from a viewpoint of dehydration (Tetsuzo Seno)• The Cellular Shear Mesh of the Chrystalls Beach Accretionary Melange: Relevance to the Active Hikurangi Margin Subduction

Thrust Interface (Richard H. Sibson)• Composition of sediments on the incoming Cocos Plate, offshore Costa Rica (Glenn Spinelli and Michael Underwood)• A Coupled Hydrological and Geomechanical Study of the Nankai Trough Earthquake Recurrence (Eyal Stanislavsky, and Grant

Garven)• Heat Flow and Flexure at Subduction Zones (Carol A. Stein)• Deformation at plate boundaries and related thrust faults. A comparison of ODP drilling with onland studies what can we infer

about the aseismic-seismic transition (Paola Vannucchi, Cesar R. Ranero and, Don Fisher)


As many of you know, the National Sci-ence Foundation was sued by the Centerfor Biological Diversity (CBD) regard-ing the use of air guns on board the R/VEwing, a research vessel owned by NSFand operated by Lamont Doherty/Colum-bia University. The suit alleged thatEwing air gun operations during a MAR-GINS Program cruise in Mexico’s Ex-clusive Economic Zone (EEZ) in the Gulfof California led to the stranding of twobeaked whales off the coast of Mexico.Few facts related to the possible causesfor the strandings were available at thetime, nor established since. For example,the time of the strandings, and thus thelocation of Ewing in relation to the posi-tion of the whales when they were knownto be alive, is unknown. The dead whaleswere examined by a NOAA-NMFS sci-entist (who by coincidence was vacation-ing at the stranding site), but a necropsywas not performed. Thus, there was nobiological evidence to show one way orthe other if the deaths were in any wayrelated to exposure to acoustic energy.Nevertheless, the Center for BiologicalDiversity (CBD), a Tucson, Arizona-based environmental group alleged thatthe R/V Ewing’s use of air guns causedthe strandings.

In an effort to halt the cruise, CBDaccused the Foundation of failing to com-ply with the National EnvironmentalPolicy Act and the Marine Mammal Pro-tection Act (MMPA) and filed a com-plaint in Federal Court in San Francisco.In late October, the Federal Magistratein San Francisco granted a temporaryrestraining order against the cruise, caus-ing it to terminate prematurely. For sev-eral reasons (good reasons, in my opin-ion), Department of Justice (DOJ) andNSF attorneys did not appeal the ruling.A couple of months later, CBD amendedthe complaint to challenge all of the

Ewing’s cruises scheduled for 2003, add-ing violations of the Endangered SpeciesAct (ESA). Shortly afterwards, DOJ andNSF attorneys, in consultation with NSFprogram staff, began negotiations withCBD. These negotiations led to a settle-ment by mid April, 2003.

NSF is pleased with the terms of thissettlement, recognizing that the litigationcould have continued for some time andbeen very disruptive to future Ewingcruises. The settlement, which formal-izes procedures already in place, allowsEwing to conduct seismic research in2003. It also preserves NSF’s argumentthat the MMPA does not apply to NSFcruises in foreign EEZs. The Founda-tion agreed to consult under the MMPAand the Endangered Species Act (ESA)with the Office of Protected Resources(OPR), National Marine Fisheries Ser-vice (NMFS) in connection with threeupcoming 2003 R/V Ewing cruises andapply for permits, if necessary. [Lamonthad initiated discussions with OPR in early2002, and at the time of the settlement,were already seeking environmental as-sessments for Ewing cruises planned in2003.]

The settlement letter also commitsNSF (and thus scientists working on theEwing) to mitigation measures to reducepossible adverse impacts of air gun op-erations on marine mammals includingmarine mammal observers, observationof a safety radius, shut down proceduresthat provide that the air gun operationswill be suspended if a marine mammalis observed within the safety zone andramp up procedures for the air gun array.[Lamont had voluntarily implementedthese procedures prior to the Gulf of Cali-fornia cruise.] In return, CBD agreed todismiss the case and will not challengeany permits issued by NMFS for theEwing’s 2003 cruises.

So what does this mean for the futureof NSF-funded seismic research and forinvestigators involved in such research?

In brief, NSF, Lamont and investiga-tors involved with research involving airguns will continue measures adopted in2002 to ensure the safety of marine mam-mals. Lamont will seek environmentalassessments for future cruises involvingair guns, submit the assessments to NSFand then NSF will submit them to OPRfor an incidental harassment or small takeauthorization (permit) as defined underthe MMPA and ESA. This process cantake 3 months to 1 year, and thus has tobe started well in advance of a researchcruise. There are also costs involvedwhich NSF has agreed to pay. As a ChiefScientist of a Ewing cruise, you shoulddiscuss this process, and what will berequired of you, with the ship operationsfolks at Lamont as soon as possible onceyour grant is funded or cruise is sched-uled. The process will likely take longer,and possibly require more extensive miti-gation measures and marine mammalmonitoring efforts, for cruises planned forcoastal waters and other areas havinghigh densities of marine mammals. It isalso possible that letters of authorizationwill not be granted for some sensitiveareas or for some areas during specificseasons of the year. The evaluation pro-cess also includes procedures for publiccomment (and legal challenges) whichcan also affect the length of time for aletter of authorization; in some cases per-haps taking much longer than 1 year.

NSF is also discussing other ap-proaches to be compliant with the termsof the MMPA and ESA. We are expect-ing guidance soon from OPR that willhelp us with our future plans. For ex-ample, can we use a different set of pro-cedures for projects involving only 1-gunor 2-gun arrays than those we describe

Update on Marine Mammals and

Research Involving Air GunsJames A. Yoder, Director

Division of Ocean Sciences, National Science Foundation4201 Wilson Boulevard, Arlington, VA 22230

Science & Policy Updates


above for the stronger sound sources?Can we seek broader authorizations cov-ering a certain class of operational sce-narios or will we continue to seek autho-rizations on a cruise-by-cruise basis? Wemay also be affected by new legislationand by other cases currently pending inFederal Court. For example, Congress iscurrently considering changes to theMMPA and ESA legislation that mightredefine the definition of harassment ormake other changes. There are also im-portant issues associated with the jurisdic-tion of the MMPA. MMPA was writtenbefore the Exclusive Economic Zone(EEZ) was defined. Most agree that theMMPA applies to the high seas but doesnot apply to U.S. ships working in the ter-ritorial seas of other countries. What aboutthe EEZ (which extends out 200 miles

from the coast)? Do U.S. scientists, andtheir foreign collaborators, need authori-zation from the U.S. Government to workon U.S.-owned research ships in the EEZof other countries, or does each countryhave the exclusive right to regulate theirown EEZ? NSF argues the latter; someothers disagree; and the Federal Courtshave not issued a definitive opinion. It isa difficult issue [Try asking, as I have, oneof your foreign collaborators if they thinkthe U.S. government has any jurisdictionin their EEZ. You will likely get an inter-esting response.]. The Division of OceanSciences realizes that this unresolved is-sue will affect some of our funded projects,and we are trying to work on practical so-lutions.

In summary, we are now working ina much more difficult legal environment

and with considerable uncertainty as towhat will and will not be possible. NSFis, however, committed to supporting re-search involving responsible use of airguns, as we believe the record shows thatmost, if not all, research projects can bedone without harming marine mammalsand without “meaningful disruption ofbiologically significant activities, includ-ing but not limited to, migration, breed-ing, care of young, predator avoidanceor defense, and feeding.”

1NRC proposed definition of Level B harass-ment, p. 69, “Marine Mammals and Low-Frequency Sound”, National Academy Press,Washington, D.C. 2000, ISBN 0-309-06886-X, 146 pp.

EUROMARGINS is a new activity of theEuropean Science Foundation (ESF) thathas as its principle focus the imaging,monitoring and modelling of the physi-cal, chemical, and biological processesthat are occurring in the passive conti-nental margin.

Within the new ESF EUROCORESscheme 14 multinational projects with atotal volume of more than 12 M Euroswill be funded. These projects will covertopics ranging from the crustal “architec-ture” of conjugate volcanic margins,through studies of slope stability on gla-cier-fed and river-fed margins, to studiesof carbonate mounds and deep-watercoral reefs and their relationship to seaf-loor seepages in margins. Together, thestudies target a significant portion of theworld’s passive continental margin sys-tem, including margins of the North At-lantic, Iberia, Mediterranean Sea, and theRed Sea.

The 14 funded proposals came froma range of 61 outline proposals of which

24 were asked to submit full proposals.These were received in March 2002 andsubsequently internationally peer re-viewed and assessed by an independentReview Panel. Following negotiationswith funding agencies participating in theEUROMARGINS Programme all 14 rec-ommended proposals could be funded.

The funding agencies that comprisethe EUROMARGINS currently includeESF Member Organisations from Bel-gium, France, Germany, Italy, Norway,Portugal, Spain, Sweden, The Nether-lands, and the UK. Links have been es-tablished with the international pro-gramme, Inter-MARGINS, and it ishoped that other nations of Europe, es-pecially those with long coastlines, willjoin EUROMARGINS in the future.

It is expected that the Programme willbecome fully operational in the secondhalf of 2003 when the Networking, hope-fully with the support of European Com-mission funds, will be put into place.

Even though it is just at the beginning

New European Funding on Margins Research -

The ESF-EUROMARGINS is on the waySvenje Mehlert1 and Anthony B. Watts2

1. European Science Foundation, 1 quai Lezay-Marnésia, 67080 Strasbourg, France2. Department of Earth Science, University of Oxford, Parks Road, Oxford OX1 3PR, United Kingdom

EUROMARGINS has already been aEuropean success in that it has broughttogether research groups that had littleprevious history of collaboration, encour-aged the support and mobility of youngscientists, and promoted the sharing ofexpensive technologies such as ships,deep-tow and seafloor instruments.

The challenge for the future will beto use this success to address the mainresearch themes of EUROMARGINSand, importantly, the links between them

EUROMARGINS is part of the ESFEUROCORES programme scheme.These programmes are designed to pro-vide an effective and efficient collabora-tion mechanism at the multi-nationallevel within Europe and to mobilise na-tional funding in basic research to tackleissues that have European-wide rel-evance. Participating funding agenciesjointly define a research programme,specify the proposal call, and support the

(Continued on page 20)


Seismogenic Zone

NSF Award number 0304946

MARGINS Postdoctoral Fellowship:The role of sediment diagenesis and de-watering on fluid and heat flow, CostaRica margin

Michael B. Underwood

University of Missouri, Columbia, MO

This award will support a MARGINSpost-doctoral fellowship to examine howubducted sediments affect fluid pressure,fluid flow patterns and frictional proper-ties within subduction zones. Thisproject will address two fundamentalquestions about the role of sediments insubduction zones: 1) how are diageneticfluid sources partitioned between opaland smectite dewatering on the CostaRica margin (and therefore how deep inthe subduction zone is most of the fluidproduced), and 2) how do along-strikevariations in heat flow and sediment com-position affect the patterns of diageneticfluid sources, fluid pressures, fluid flow,and possibly the updip limit of seismic-ity within the subduction zone?


Collaborative Research: Seismic veloc-ity, compaction, andpore pressure inunderthrust sediments, Nankai sub-duction zone

Demian Saffer1, Gregory Moore2, andHarold Tobin3

1. University of Wyoming, Laramie, WY2. University of Hawaii, Honolulu, HI3.New Mexico Tech, Socorro, NM

Funds are provided to better constrain in-situ pore pressure, relationship between

pore pressure and porosity and compac-tion state of sediments in the Nankaimargin using existing 3-D seismic data.Pore pressure and compaction state ofunderthrust sediments may be a key con-trol on fault behavior because thedecollement localizes at the top of thesesediments. The work will provide impor-tant information necessary for the drill-ing of the Nankai seismogenic zone un-der IODP.

Subduction Factory

NSF Award number0305292

A numerical investigation of the rela-tive importance of different meltingmechanisms at volcanic arcs

James Conder

Washington University, St. Louis, MO

Under this award, the PIs will use finite-element viscous flow models to study thedifferent melting mechanisms likely tobe occurring beneath volcanic arcs. Thethree main mechanisms to be studied are:flux melting from hydration of the mantlewedge from the subducting slab, decom-pression melting that occurs when a tem-perature-dependent mantle rheology isconsidered, and possible sediment melt-ing at the subducting slab surface. Dif-ferent arcs can have large differences inthe amount of magmatic production andmay also vary in the relative productionof each melting mechanism. The PIs willinvestigate the various parameters affect-ing the production of each meltingmechanism such as slab dip, subductionrate, subducting and overlying plate ages,etc. Some parameters will have a greaterinfluence on one mechanism than an-other, leading to the possibility that thedominant melting mechanism could

change from one arc to another, and af-fecting what is observed at real arcs.


Quantification of metamorphic de-volatilization in the subduction factoryfocus sites: implications to fluid fluxes,seismicity, and volatile recycling

Derrill Kerrick

Penn State University, University Park, PA

Because many hydrous marine sedimentsentering subduction zones lack CO

2 (i.e.,

lack carbonate minerals), dehydrationwould be dominant over decarbonationupon subduction. Under this funding, thePIs will compute subduction zonedevolatilization for the major lithologictypes of CO

2-free hydrous marine sedi-

ments: red clays, hydrothermal (ferrugi-nous) clays, turbidites, and mixed litholo-gies, i.e., radiolaria/diatom oozes mixedwith clays or volcanic ash, using a vari-ety of constraints from ODP drill sitesoff the Izu-Bonin-Marianas and CostaRica-Nicaragua. Because the carbonatecontent of altered basalts in the upperoceanic crust increases with age, the PIswill compare metamorphic devolati-lization of oceanic metabasalts in subduc-tion zones with Jurassic crust (e.g.,Marianas) with those subducting lateCenozoic crust (e.g., Costa Rica), and willquantify the relative contributions of thevarious volatile-bearing assemblages andassess the depth distribution of volatile re-lease. A primary goal of the proposed re-search is to quantify metamorphic devola-tilization for the lithologies entering thesesubduction zones and to compare the re-sults with the distribution of earthquakehypocenters and volcanic activity associ-ated with each subduction zone.

Funded Programs

Funded MARGINS Programs 2003These are the funded MARGINS Proposals for the fiscal year 2003. This information is also available at the awards database ofthe MARGINS web site at www.ldeo.columbia.edu/margins/MARGINSawards.html, together with abstracts of all NSF-funded MARGINS Projects.



Melt inclusions in Izu arc lavas: exam-ining slab-derived contributions to in-tra-oceanic arc magmas and the roleof volatiles in the subduction factory

Adam Kent

Oregon State University, Corvallis, OR

Via a Japanese, American, and Europeancollaboration, this study will analyzemajor, trace and volatile elements (H

2O,

CO2, S, Cl, F) and B and H isotopic com-

position in melt inclusions and lavas fromthe Izu arc using petrographic, electronmicroprobe, ion microprobe and laser-ablation ICP-MS techniques. Melt inclu-sions will provide primary constraints onthe major, trace and volatile element con-tents and boron and hydrogen isotopecompositions of primitive Izu arc melts,and this data will test and constraingeochemical, petrological, geophysicaland thermal models for subduction in thisregion, one of the MARGINS programselected study areas, and elsewhere.


Collaborative Research: Constraining thevolatile and slab flux in the Izu-Bonin-Marianna margin using geothermal flu-ids, phenocrysts, and melt inclusions

Tobias Fischer1, David Hilton2, and ErikHauri3

1. University of New Mexico, Albuquerque, NM2. Scripps Inst. of Oceanography, La Jolla, CA3. Carnegie Institute of Washington, Washington, DC

Under this award, the PIs will carry outan integrated study of volatiles in the Izu-Bonin-Marianas margin that includes theanalyses of specific volatiles (H

2O, CO

2,

Cl, S) and fluid soluble elements (Li, B,K, Rb, Ba and others) as well as theirstable isotope (dD, d11B, d13C, d18O, d34S)systematics utilizing SIMS measure-ments of melt inclusions of recentlyerupted tephra. This data set will becomplemented by CO

2 and He abundance

and isotopic measurements (d13C and

3He/4He) in erupted phenocysts and dis-charging volcanic and hydrothermal flu-ids. Additionally, the study will measurethe complete gas composition and the N-isotopes of the hydrothermal fluids inorder to determine the present-day totalvolatile flux from the entire arc throughnormalization to ground-based SO

2 re-

mote sensing measurements. The com-bined data set will allow the PIs to quan-tify the slab flux in terms of volatile com-position (melt inclusion data), the sourceof the slab flux in terms of oceanic base-ment, subducted carbonates or organicsediments (CO

2-He and N

2-He system-

atics), the present day volatile flux to theatmosphere from the slab and mantlewedge (SO

2 flux and volcanic gas com-

positions). The study addresses the fluxand composition of volatiles into and outof the IBM system and the distributionof volatiles in the mantle and its geo-chemical evolution through time.


Mantle dynamics of the Izu-Bonin-Marianna subduction system

Matthew Fouch

Carnegie Institute of Washington, Washington, DC

This study provides new constraints onmantle flow and dynamics within the Izu-Bonin subduction system through a com-bination of seismic observations and nu-merical modeling experiments. Results ofthis work are providing key informationregarding mantle processes in convergentmargins, including the means of mantlemagma transport and the geometry ofstrain partitioning between tectonic platesand the sublithospheric mantle.

In this coupled approach, the follow-ing issues are being addressed specifi-cally: 1) the 3-D distribution of uppermantle anisotropy and its implications forstrain partitioning and mantle flow in theIzu-Bonin subduction zone; and 2) theinterpretation of seismic anisotropy re-sults, particularly their relationship toboth mantle transport processes and the

degree of coupling between tectonicplates and sublithospheric mantle.

The seismic component of the projectinvolves shear wave splitting analysis fora unique set of shear phases, includinglocal S, teleseismic SKS, and sS-S differ-ential splitting. The Izu-Bonin region isparticularly well-suited for the proposedseismic studies, as earthquakes generatedin Izu-Bonin provide an excellent datasetof seismic phases that sample a broad por-tion of the study area. The availability ofbroadband waveforms of Izu-Bonin earth-quakes have been recorded by many high-resolution seismographs and allows con-straint of both lateral variations and thedepth distribution of anisotropy for theIzu-Bonin system.The numerical modeling component of theproject involves calculation of 3-D mod-els of mantle flow for a range of physicalmodel parameters. To determine the rela-tionship of mantle flow to the seismicanisotropy observations, flow models arebeing used to calculate predicted anisot-ropy using appropriate elastic parametervalues from a range of deformation stud-ies, and comparing the modeling resultswith the seismic anisotropy results.

Source to Sink


Collaborative Research: Late Quater-nary Siliciclastic and carbonate sedi-ments and sediment fluxes on theslopes and basin floors of the Ashmoreand Pandora troughs, Gulf of PNG

André Droxler1, Samuel Bentley2, andLarry Peterson3

1. Rice University, Houston, TX2. Louisiana State University, Baton Rouge, LA3. RSMAS, Miami, FL

Funds will be provided to investigatesedimentation processes in the mixedsiliciclastic carbonate slope and basinenvironment in the Gulf of Papua as apart of the integrated source-to-sink ex-periment at the Fly River-Gulf of Papua


focus site of MARGINS. Through the useof detailed acoustic surveys and seabedand water column sampling the proposerswill estimate sediment fluxes and trans-port pathways from the shelf edge andcarbonate reef margins to the ultimatesinks of the Ashmore and Pandoratroughs over the last interglacial cycle.The work will lead to an understandingof the history of sediment accumulationon the continental slope and the deepocean for the mixed system as well assediment fluxes and transport mecha-nisms by identifying timing and geom-etry of deposition in the Gulf. The ulti-mate objective is to develop a model formixed carbonate-siliciclastic deposition.


Collaborative Research: Developing aQuantitative understanding of Clino-form formation, Gulf of Papua

Neal Driscoll1, Rudy Slingerland2, andJohn Milliman3

1. Scripps Inst. of Oceanography, La Jolla, CA2. Penn State University, University Park, PA3. Virginia Inst. of Marine Science, Cloucester, VA

This is a project to study the processesof sediment transport and accumulationthat lead to development of the clino-forms on the Gulf of Papua (GoP) conti-nental shelf. Shelf clinoforms are thedominant components of continental-margin stratigraphy, but little is knownabout the processes that create them. Bycombining field research (seismic profil-ing and piston coring) and numericalmodeling, quantitative understanding ofmid-shelf clinoform development at geo-logic time scales can be developed. Thesestudies will test the hypothesis that thepredominant mechanism for creating thepresent-day clinoform morphology isacross-shelf gravity flow of fluid muds,whereas underlying strata may haveformed in different conditions in responseto changing rates of sea-level rise andsediment supply.

Rupturing Continental Lithosphere


Geodetic constraints on the kinemat-ics and dynamics of active rifting of thenorthern and central Red Sea

Robert E. Reilinger

MIT, Cambridge, MA

This project uses the Global PositioningSystem (GPS) to measure active defor-mation along the rift margins of the RedSea. The project is being undertaken incooperation with partner institutions inEgypt, Saudi Arabia, Eritrea, and Sudan.The ultimate objective of this research isto understand better the dynamics of con-tinental rifting The approach includesboth continuously recording GPS stationsinstalled along the rift and survey GPSobservations to determine variations indeformation style along and normal to therift system. The GPS results are provid-ing new constraints on the mechanics ofcontinental rifting thereby adding to ourunderstanding of the basic forces driv-ing continental deformation and the rheo-logical character of the continental litho-sphere. In addition, this project is help-ing to transfer GPS technology to thehost-country partners and is providingquantitative information on plate motionsand rates of strain accumulation that aredirectly useful for evaluating and miti-gating earthquake hazards.


Collaborative Research: Integratedthermochronological and structuralinvestigation of the Saudi Arabian RedSea rift margin: implications for therupturing of continental lithosphere

Gomaa Omar1 and Daniel Stockli2

1. University of Pennsylvania, Philadelphia, PA2. Caltech, Pasadena, CA

The PIs will undertake a structural andthermo-chronological study of the Saudi

Arabian Red Sea margin as a part of theMARGINS “Rupture of the ContinentalLithosphere” initiative. This margin of-fers an exceptional opportunity to studythe processes associated with continen-tal rifting and how extensional strain isdistributed in space and time. The PIs willemploy apatite fission-track and (U-Th)/He thermo-chronology and structuralmapping in the study area to achieve theirobjectives. The study will contribute to amore comprehensive understanding ofthe Red Sea rift and will form a part ofthe overall geological/geophysical workplanned in this area under the MARGINSprogram. A close collaboration with theSaudi Geological Survey is envisaged.


Collaborative Research: Upper MantleStructure beneath the Gulf of California

Jim Gaherty1 and John Collins2

1. Georgia Tech, Atlanta, GA2. Woods Hole Ocean. Inst., Woods Hole, MA

In this experiment, which is part of theNSF Margins initiative on Rifting Con-tinental Lithosphere, the investigators aredeploying 18 wide-band ocean bottomseismographs (OBS) in the Gulf of Cali-fornia for a period of 15 months. Theseseismographs are recording naturallyoccurring seismicity (over 200 moderateand large earthquakes) from around theglobe. Using these seismic recordings,the investigators are constructing imagesof the mantle beneath the Gulf and thesurrounding region, providing a meansto evaluate the degree to which mantleprocesses control lithospheric rupture andthe initiation of seafloor spreading in theGulf of California. The experiment isfocused on two questions that are particu-larly important for achieving the goalsof the Rifting Continental Lithosphereinitiative: (1) Is the upper-mantle directlyunderlying Gulf of California extensionanomalously hot? (2) To what extent doNorth-South variations in extensional

Funded Programs


MARGINS Newsletter No. 10, Spring 2003 MARGINS Post-docs

MARGINS Post-Doctoral Fellows 2003Beginning this year, the MARGINS Program is funding a number of post-doctoral fellows, both within the special MARGINSPost-Doctoral Fellowship Program and within the regular NSF-MARGINS program (cf. preceding pages). The MARGINSOffice is proud to announce the names of the successful post-doctoral fellows: James Conder, Alison Shaw, and Glenn Spinelli— congratulations to you all. The MARGINS Office wishes them success in their post-doctoral research endeavors. Below, thethree post-doctoral fellows introduce themselves and their projects:

James ConderWashington University, St. Louis, MO

Working as a post-doc at WashingtonUniversity has been a great opportunityto study geologic processes at volcanicarcs and back-arc basins and also to be-come involved with the MARGINS pro-gram. Previous and ongoing WashU seis-mic experiments at the Tonga andMariana subduction zones have helpedstimulate my interest in magma produc-tion and migration at these geologicallyimportant regions.

Growing up in Salt Lake City helpedgive me an appreciation for the outdoorsand the many diverse, but interlinked, as-pects of the natural and physical sciences.I discovered Geology as an undergraduateat the University of Utah, and worked for ayear at a mining exploration company be-fore heading to the East Coast for graduateschool. Although my snowboarding skillsseverely atrophied after leaving theWasatch Mountains, it has been an im-mensely rewarding experience, particularlybecause of the interaction with the manygreat people and discussions of interestingresearch I have encountered within the geo-physical community.

While a graduate student at BrownUniversity, I learned the value of com-bining different seismic observationswith other methods, particularly numeri-cal modeling, to understand mantle flowand melt processes. My research atBrown primarily focused on the South-east Indian Ridge and the East PacificRise. One thesis chapter demonstratedwith numerical models of mantle flowincorporating pressure- and temperature-dependent viscosity that asthenosphericflow driven from one side of the spread-ing axis to the other can account for theunexpected degree of asymmetry ob-served across the East Pacific Rise fromthe MELT experiment. Applying thesesame modeling techniques to understandthe observed asymmetric seismic struc-ture of the Lau back-arc spreading cen-ter led to the find that decompressionmelting should be expected beneath somevolcanic arcs as the subducting slab vis-cously erodes the base of the overlyinglithosphere. Models using temperature-dependent viscosity also predict slab tem-peratures >100 deg C warmer thanisoviscous models. These observationsput volcanic arcs in the interesting posi-tion of potentially having three possible

melting mechanisms for magma genera-tion: wedge hydration, wedge decom-pression, and slab heating. As a MAR-GINS post-doc, I plan to use numericalmodels along with seismic observationsto map out how the importance of eachmelting mechanism varies from arc-to-arc as the thermal structure and othergoverning parameters at subductionzones change.

Alison ShawScripps Inst. of Oceanography, La Jolla, CA

After completing my undergraduate de-gree in geosciences at McGill University,I left the Great White North to pursuegraduate studies in sunny Southern Cali-fornia at Scripps Institution of Oceanog-raphy. During the course of my Ph.D.research at Scripps with Dr. David Hilton,I had the opportunity to work on a MAR-GINS related project investigating theCO2 flux though the Central American

Arc. Using He-C relationships in geother-mal fluids (fumaroles, hot springs andgeothermal well gases) collected fromvarious volcanic centers along the arc, Iwas able to assess the provenance of thevolcanic C output, allowing for an esti-mate of how much of the C input at thetrench (as pelagic carbonates, organic Cand altered oceanic crust carbonate) wasrecycled through the arc system. As acomplement to my geothermal fluid arc



Glenn SpinelliUniversity of Missouri, Columbia, MO

I am excited to be starting a MARGINSpost-doctoral fellowship this year. Afterspending most of my life near the edgesof this continent (including growing upin New Jersey and attending grad schoolat the University of California, SantaCruz), it seems natural to head to theheartland (Missouri) to study continen-tal margins. After getting a B.S. at PennState, I went to UC Santa Cruz where myresearch encompassed hydrogeology andsedimentology — ranging from ground-water seepage into San Francisco Bayand fluid seepage through sediments onthe Juan de Fuca Ridge flank, to sedi-mentation patterns on northern Cali-fornia’s Eel River margin. As a MAR-GINS post-doctoral fellow, I will furtherdevelop my interests in both hydro-geology and sediments by studying sedi-ment dewatering within the Costa Ricamargin subduction zone.

Sediments subducted off Costa Ricahave high opal and smectite contents

(both contain a large amount of water thatis expelled at moderate temperatures andpressures within the shallow subductionzone). Smectite dewatering has beenshown to significantly affect pore fluidpressure and chemistry in the subductionzones of Barbados and Nankai. On theCosta Rica margin, opal dewatering pro-vides another source of water during sedi-ment diagenesis. Additionally, in Costa

studies, my postdoctoral research at theCarnegie Institution of Washington withDr. Erik Hauri will focus on melt inclu-sions in recently erupted tephras from theIzu-Bonin-Marianas arc system. Meltinclusions are thought to represent pre-eruptive melts, and thus offer the excit-ing possibility to look at the compositionof sub-arc partial melts. Since it is as-sumed that inclusions remain isolatedafter entrapment, they are thought to pre-serve the characteristics of primitivemelts and are less influenced by magmachamber processes than erupted lavas.This study will be part of a collaborativevolatile study of the arc using geother-mal fluid data and remote sensing tech-niques, along with melt inclusions inmafic phenocrysts, to gain a better un-derstanding of how volatiles are cycledthrough arc systems.

Rica, large along-strike variations in heatflow may lead to differences in the depthwithin the subduction zone at which thedewatering reactions occur. This has thepotential to generate along-strike fluidpressure gradients and therefore marginparallel fluid flow within the subductionzone. Fluid pressure and fluid flow pat-terns in response to sediment dewateringin the subduction zone, in turn have im-plications for fault strength and poten-tially the location of the updip limit ofseismicity.

This study will consist of two phases:a characterization of the sediments off-shore Costa Rica (in cooperation withMike Underwood at the University ofMissouri), and modeling of sedimentdewatering and fluid flow within theCosta Rica margin subduction zone (incooperation with Demian Saffer at theUniversity of Wyoming).

MARGINS Post-docs

international peer review of the applica-tions, with final funding decisions resid-ing with participating national bodies.ESF acts as a catalyst by conducting theinternational peer review, offering projectmanagement, and by the “networking”of scientists who are involved in the in-dividual projects.

For more information on EURO-MARGINS please contact the ESFwebsite at: www.esf.org/euromargins.

style correlate with upper-mantle veloc-ity variations? The OBS deployment alsoprovides the means to better character-ize seismically active faults within theGulf of California, improving the assess-ment of the natural hazards environmentof the region. The Gulf of California OBSarray builds two ongoing Margins-fundedexperiments: the NARS-Baja onshorebroadband seismic array, and an active-source crustal survey. The ocean-bottomseismic data collected in this experimentwill be available to any interested inves-tigator 2 years following instrument re-covery through the IRIS Data Manage-ment Center.

Continued from page 19, Alison Shaw:Continued from page 18, Funded Programs:Continued from page 19, EUROMARGINS:


MARGINS Steering Committee highlightsOlaf M. Svenningsen

Lamont-Doherty Earth Observatory, 61 Route 9W, Palisades, New York 10964, USA

Steering Committee highlights

On March 27-28,2003, the MARGINSSteering Committee met at the NationalScience Foundation headquarters in Ar-lington, VA. The agenda included the fol-lowing items (items covered in otherplaces in this newsletter are indicated inbrackets):

1. Welcome by the MARGINS Chair.2. NSF Program managers’ report on

MARGINS and MARGINS funding(see From the Chairman’s desk, page6, and Funded Programs, page 16),

3. MARGINS Fellowships (see pages19-20)

4. The marine mammals issue and rami-fications for acoustic research and theMARGINS Program (editorial andYoder)

5. Official OCE policy regarding pro-posals to work in politically senistiveareas.

6. MG&G Databases, the MARGINSperspective

7. Review of the MARGINS program8. MARGINS Science Plan publication9. Meeting reports

Below are summaries of some of the moreimportant discussions and decisions thatare not covered elsewhere in this news-letter:

1. Two new and one old-new memberwere introduced and welcomed ontothe committee: Mark Reagan of theUniversity of Iowa and Geoff Abersof Boston University will both rep-resent the Subduction Factory. JulieMorris of Washington University inSt. Louis, MO is the new MARGINSChair (see next page, Office News).

2. The MARGINS Funding situation iscovered in the Chair’s editorial onpage 6.

3. 2003 is the first year of MARGINSPost-Doctoral Fellowships, and threefellowships were awarded by NSF.The MARGINS post-docs are pre-sented on the preceding pages (19-20).

4. The impact of acoustic research onmarine mammals, and the impact andstatus of the consequences of Gulfof California incident in September2002, was discussed in detail. JamesYoder, Director of Ocean Sciences atNSF, presented an update on the le-gal status of this issue (see page 14).

5. OCE Guidelines for Fleet Security(posted on NSF website, http://www.nsf.gov/pubs/2002/nsf 02055/nsf02055_2.htm). In summary:

• PIs should consider regions of poten-tial danger before submitting;

• Where possible, cruises should beplanned to avoid regions for whichare not automatically insured throughexisting global coverage;

• OCE currently advises reviewers andpanelists not to introduce security is-sues as a review criterion;

• Successful proposals to such areas willbe held until determination is made re-garding insurance and security;

• NSF does not require operators to sailto region or port deemed unsafe (no in-surance, no cruise support from NSF);

6. Davip Epp of NSF summarized datamanagement efforts at NSF (see is-sue 9, Fall 2002, of the MARGINSNewsletter), and stated that NSF-MG&G reserves 8% of its budget forthese purposes. Walt Snyder gave apresentation of the GEON project(www.geongrid.org) and its pos-sible implications for MARGINSdata management.

7. NSF will conduct a “midlife” reviewof the MARGINS Program in early2004. The purpose is to review, notto evaluate, the program. The result-ing report is intended to be a man-agement tool for both the NSF andthe MARGINS Office. For the re-view, documentation will be neces-sary, and one important componentis the publication of all of the sci-ence plans (see next item). An over-view of the history of MARGINS isnecessary for the review and theSteering Committee was chargedwith producing this material. The re-view will be posted on the MAR-GINS website.

8. The MARGINS Science Plan/thescience plans for the four initiativeswill be published by the end of thesummer of 2003. The final step inthese preparations was the review ofthe SEIZE science plan after theSEIZE 2003 Theoretical Institute.The MARGINS Science Plan will bepublished before the Office moves toSt. Louis in October.

9. A report from the SEIZE 2003 Theo-retical Institute begins on page 11 ofthis issue. The Source-to-Sink TownMeeting held at the AGU 2002 FallMeeting to present the revised sci-ence plan was attended by c. 80people. The discussion at the townmeeting was concerned more withhow the science plan had been re-vised rather than its contents. The re-vised science plan was accepted byNSF Program Managers and thecommunity.

MARGINS Newsletter No. 10, Spring 2003 Office News

MARGINS Office NewsOlaf M. Svenningsen

Lamont-Doherty Earth Observatory, 61 Route 9W, Palisades, New York 10964, USA

Website update

The MARGINS website has grown everbigger and more complex, and this hasnecessitated an update, aiming to facili-tate within-site navigation and accessi-bility. The update will be ongoingthroughout the summer of 2003, but sev-eral important changes have already beenmade:

1. The navigation bar has been changedto include direct links to the variousdata pages available within thewebsite.

2. The “About MARGINS” page hasbeen expanded to four pages, cover-ing; the MARGINS Program; theSteering Committee; the MARGINSOffice, and finally the website. Asitemap (see Figure 1) has beenadded as graphic table of contents forthe main pages and sub-sites of theMARGINS website.

3. The “Meetings” page has beenchanged, and instead of providing along (sometimes very long) text listof upcoming meetings, each link nowopens a separate page with informa-tion about one particular meeting.These pages have been designed tobe printable directly from a webbrowser .

4. The within-site search engine hasbeen complemented with two exter-nal science search engines.

5. Finally, but very important: Over thesummer, many documents will be re-moved from the root directory of thewebsite, which presently contains c.several hundred documents, making

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T&E Institutes

Related Websites

Steering CommitteeMARGINS OfficeWebsite (this page)

Rupturing Continental LithosphereSeismogenic ZoneSubduction FactorySource-to-Sink

MARGINS NSF Awards DatabaseMARGINS Metadata ServerMARGINS Publications

Presentation MaterialMARGINS FellowshipsProposal MaterialTravel Documents

Gulf of CaliforniaRed Sea/Gulf of SuezNankai TroughCosta Rica/NicaraguaIzu-Bonin-Mariana

Papua New GuineaNew Zealand

the website unnecessarily cumber-some to maintain. No documents willbe removed, but the URL, or web ad-dress, to many documents willchange, and bookmarks may have tobe updated. Since the entire websitewill move to a different server in Oc-tober, this is a suitable time to reviewyou bookmarks anyway.

Figure 1. The recently posted new sitemap of the MARGINS website. Each label on this mapis also a link to the different pages and sub-sites.

Figure 2. View to the west of the Palisades Cliffs across the Hudson River from Hastings-on-Hudson, NY. Lamont-Doherty EarthObservatory and the MARGINS Office are perched on top of the cliffs. New York City is c. 15 miles to the south.

Where is the MARGINS Office?


MARGINS OfficeOlaf SvenningsenLamont-Doherty Earth ObservatoryOceanography Building, room 30561 Route 9W, P.O. Box 1000Palisades, New York 10964-8000Tel: (845) 365-8665, or 8509Fax: (845) 365-8156e-mail: [email protected]: [email protected]: http://www.ldeo.columbia.edu/margins

Garry Karner, ChairLamont-Doherty Earth Observatory61 Route 9W, P.O. Box 1000Palisades, New York 10964Tel: (845) 365-8355e-mail: [email protected]

MARGINS Steering Committee

Bilal HaqMarine Geology and Geophysics Program

Division of Ocean SciencesTel: (703) 292-8582Fax: (703) 292-9085

e-mail: [email protected]

Paul DauphinOcean Drilling Program

Division of Ocean SciencesTel: (703) 292-8581Fax: (703) 292-9085


David FountainTectonics Program

Division of Earth SciencesTel: (703) 292-8552Fax: (703) 292-9025


NSF Program DirectorsNational Science Foundation, 4201 Wilson Boulevard, Arlington, Virginia 22230

This information is also posted on the MARGINS website, where it is continuously updated.

Contact Information

Julie Morris, Chair-electDepartment of Earth and Planetary SciencesWashington University in St. LouisCampus Box 1169One Brookings DriveSaint Louis, MO 63130Tel: (314) 935-6926e-mail: [email protected]

Geoffrey AbersDepartment of Earth SciencesBoston University5 Commonwealth AvenueBoston, MA 02215Tel: (617) 353-2616e-mail: [email protected]

Frederick M. ChesterDepartment of Geology & GeophysicsMail Stop 3115College Station, TX 77843Tel: (979) 845-3296e-mail: [email protected]

Rebecca J. DorseyDepartment of Geological Sciences1272 University of OregonEugene, OR 97403-1272Tel: (541) 346-4431e-mail: [email protected]

Greg HirthDepartment of Geology and GeophysicsWoods Hole Oceanographic InstitutionWoods Hole, MA 02543Tel: (508) 289-2776e-mail: [email protected]

Scott LinnemanGeology Department and Science Education GroupWestern Washington University516 High StreetBellingham,WA 98225-9080Tel.: (360) 650-7207e-mail: [email protected]

Anne MeltzerEarthScope liaisonDept. of Earth & Environmental SciencesLehigh University31 Williams DriveBethlehem, PA 18015-3188Tel.: (610) 758-3660e-mail: [email protected]

John MillimanVirginia Institute of Marine ScienceCollege of William and MaryP.O. Box 1346Cloucester Point, VA 23062Tel: (804) 684-7105e-mail: [email protected]

Mark ReaganDepartment of GeoscienceUniversity of IowaIowa City, IA 52242Tel: (319) 335-1802e-mail: [email protected]

Thomas H. ShipleyInstitute of GeophysicsUniversity of Texas4412 Spicewood Springs Road, Building 600Austin, Texas 78759Tel: (512) 471-0430e-mail: [email protected]

Eli A. SilverUniversity of California, Santa CruzEarth Science Department & Institute of Tectonics1156 High StreetSanta Cruz, California 95064Tel: (831) 459-2266e-mail: [email protected]

Rudy SlingerlandDepartment of GeosciencesPenn State University503 Deike BldgUniversity Park, PA 16802Tel: 814-865-6892e-mail: [email protected]

Patricia WibergDepartment of Environmental SciencesUniversity of VirginiaP.O. Box 400123Charlottesville, VA 22904-4123Tel: (434) 924-7546e-mail: [email protected]

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This newsletter is supported by the National Science Foundation underGrant No. OCE 00-79660. Any opinions, findings, and conclusionsexpressed in it are those of the authors and do not necessarily reflect theviews of the National Science Foundation.

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Upcoming Meetings:

• Ocean Margin Research ConferenceSeptember 15-17, 2002 in Paris, France

—• The Geological Society of America 2003

Annual Meeting & ExpositionNovember 2-5, 2002 in Seattle, Washington

—• AGU 2003 Fall Meeting

8-12 December 2003, San Francisco, California—

More information about MARGINS-related meetings are posted on theMeetings page at the MARGINS web site:

http://www.ldeo.columbia.edu/margins

Newsletter No. 10, Spring 2003 - USGS · Page 2 MARGINS Newsletter No. 10, Spring 2003 ment...

Documents

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