Potential targets for shale-oil and shale-gas...

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Arizona Geological Survey www.azgs.az.gov | repository.azgs.az.gov OPEN-FILE REPORT OFR-13-09 V. 1.O Potential targets for shale-oil and shale-gas exploration in Arizona Steven L. Rauzi & Jon E. Spencer Arizona Geological Survey July 2013 Team of geoscientists investigating the Neoproterozoic Chuar Shale in Nankoweap Canyon

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Arizona Geological Surveywww.azgs.az.gov | repository.azgs.az.gov

OPEN-FILE REPORT OFR-13-09 V. 1.O

Potential targets for shale-oil and shale-gas exploration in Arizona Steven L. Rauzi & Jon E. Spencer

Arizona Geological Survey

July 2013

Team of geoscientists investigating the Neoproterozoic Chuar Shale in Nankoweap Canyon

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Arizona Geological Survey

M. Lee Allison, State Geologist and Director

Manuscript approved for publication in July 2013Printed by the Arizona Geological Survey

All rights reserved

For an electronic copy of this publication: www.repository.azgs.az.govPrinted copies are on sale at the Arizona Experience Store

416 W. Congress, Tucson, AZ 85701 (520.770.3500)

For information on the mission, objectives or geologic products of the Arizona Geological Survey visit www.azgs.az.gov.

This publication was prepared by an agency of the State of Arizona. The State of Arizona, or any agency thereof, or any of their employees, makes no warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report. Any use of trade,

product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the State of Arizona.

___________________________

Recommended Citation: Rauzi, S.L. and Spencer, J.E., 2013, Potential targets for shale-oil and shale-gas exploration in Arizona. Arizona Geological Survey Open File Report, OFR-13-09 v. 1, 9 p.

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Potential targets for shale-oil and shale-gas

exploration in Arizona

by

Steve Rauzi Oil and Gas Administrator

&

Jon Spencer Senior Geologist

Arizona Geological Survey Open-File Report 13-09

July 2013

Arizona Geological Survey 416 W. Congress St., #100

Tucson, AZ 85701 www.azgs.az.gov

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Introduction

The recent development of horizontal drilling techniques and application of hydraulic fracturing

to horizontal wells has dramatically increased oil and gas production in the U.S., notably in areas

with extensive organic-rich shale and calcareous shale deposits. Shale formations that contain

hydrocarbons without sufficient porosity and permeability to yield economic amounts of oil and

gas with conventional drilling techniques are being reconsidered in light of these technological

advances. In this report we identify 10 rock formations in Arizona that consist dominantly of

shale or phyllite (very low grade metamorphic shale) that represent potential areas of interest for

shale-oil and shale-gas exploration (Table 1, Fig. 1). Many of these units are weakly

metamorphosed, and are perhaps too thermally mature to contain recoverable oil or gas in known

exposures. However, lateral equivalents of these units may be less metamorphosed and so

contain recoverable hydrocarbons. These equivalents could be present but concealed, especially

in structurally complex areas in southeastern Arizona.

Table 1. Potential targets for shale-oil and shale-gas exploration in Arizona

Unit and Age Location Notes

Mancos Shale –

Upper Cretaceous

Northern

Arizona

Unknown TOC, dark gray, extent is Black Mesa

Fort Crittenden Formation –

Upper Cretaceous

Southeastern

Arizona

Basal shale, black Physa, unknown extent

McCoy Mountains Formation –

Upper Jurassic to Upper

Cretaceous

Southwestern

Arizona

Maroon, purple, gray mudstone and phyllite

Apache Canyon Formation,

Bisbee Group – Cretaceous

Southeastern

Arizona

Thick black shale, Whetstone Mountains, Sonoita

area

Crystal Cave Formation –

Jurassic

Southeastern

Arizona

Thick black shale in structurally complex area

DBK Shale, Hermosa Group –

Pennsylvanian

Northern

Arizona

Persistent 10 ft black shale in Dineh-bi-Keyah Oil

Field, uncertain extent

Aneth Shale –

Devonian

Northern

Arizona

Production from possible correlative at Walker

Creek Oil Field

Morenci (Portal/Percha) Shale –

Devonian

Southern

Arizona

Equivalent to fissile black Percha Shale in New

Mexico

Bright Angel Shale –

Cambrian

Northern

Arizona

Questionable TOC, better seal than source

Walcott Shale, Chuar Group –

Neoproterozoic

Northern

Arizona

Good TOC (up to 8.29%), unit is preserved in a

Neoproterozoic half graben north of Grand

Canyon

Pioneer Shale, Apache Group –

Mesoproterozoic

Central Arizona Extensive exposures of phyllite and fine-grained

sandstone

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Figure 1. Potential targets for shale-oil and shale-gas exploration in Arizona. See Table 1 for brief

description and age of each unit.

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CHARACTERISTICS OF ARIZONA SHALE AND PHYLLITE UNITS

Upper Cretaceous Mancos Shale

No geochemical analyses, unknown total organic carbon content (TOC).

“The Mancos Shale is predominantly dark gray, bluish-weathering, siltstone and

claystone.” (Nations and others, 2000, p. H11).

Extends across entirety of Black Mesa in Coconino, Navajo, and Apache counties in

northeastern Arizona (Rauzi and Spencer, 2013).

The Mancos “is about 700 ft thick on the north side of Black Mesa and thins to about 475

ft in the southernmost complete exposures at Blue Point on Padilla Mesa. It continues to

thin southward toward its pinch out near Show Low” (Nations and others, 2000, p. H11).

Regional stratigraphic cross sections from the Kaiparowits Basin in Utah through Black

Mesa and to the San Juan Basin in New Mexico are published in Nations (1989).

Penetrated by three exploration wells in Arizona: Skelly 1 Hopi-A, Amerada 1 Hopi, and

R.Y. Walker 1 Navajo. Well logs and Mancos Shale sample cuttings for all three wells

are available at the AZGS.

Upper Cretaceous Fort Crittenden Formation

No geochemical analyses, unknown total organic carbon content (TOC).

Basal black shale, randomly spaced zones rich in black, thin-shelled Physa and fossil

wood, fossiliferous mudstone records marginal lacustrine mudflat (Hayes, 1987).

Extends across eastern Pima, Santa Cruz, and western Cochise counties in southern

Arizona.

Shale member ranges up to 850 ft thick.

Generalized stratigraphic and columnar sections are published in Inman (1987) and

Hayes (1987).

Late Jurassic - Late Cretaceous McCoy Mountain Formation

No geochemical analyses, unknown total organic carbon content (TOC).

Maroon, purple, gray mudstone. “The mudstone member (900 m thick) consists of thick

intervals of gray siltstone and mudstone interbedded at regular intervals with thin

horizons of sandstone and conglomerate” (Harding and Coney, 1985, p. 760).

“Homogenous mudstone and siltstone interbedded with minor sandstone and

conglomerate are common in the uppermost part of the unit (mudstone member).”

(Tosdal and Stone, 1994, p. 478).

Extends westward across southern La Paz County from southeast of Quartzite into

California (Spencer and others, 2011).

Mudstone member ranges up to 2900 ft thick (Harding and Coney, 1985, p. 760).

Generalized stratigraphic and columnar sections are published in Harding and Coney

(1985) and Tosdal and Stone (1994).

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Early Cretaceous Apache Canyon/Schellenberger Formations of Bisbee Group

No geochemical analyses, unknown total organic carbon content (TOC).

Thick black shale. “The Apache Canyon Formation (820-1640 ft thick) is composed

dominantly of thin-bedded dark-gray to black mudstone and limestone in varying

proportions.” (Dickinson and others, 1989, p. 453-454).

Extends across most of southern Cochise County in southeastern Arizona but primarily

Whetstone Mountains and Sonoita areas.

Ranges from 820-1640 ft thick across the area with 1000 ft of dark to black shale in the

Mountain States 1A well in 29-19s-18e. Graphic lithologic log and Apache Canyon

sample cuttings for are available at the AZGS.

Stratigraphic and columnar sections are published in Hayes (1970) and Dickinson and

others (1989).

Middle-Late Jurassic Crystal Cave Formation

No geochemical analyses, unknown total organic carbon content (TOC).

“Dominant lithic type is black to dark-gray siltstone and mudstone with a blocky

character, generally lacking in fissility…Plant fragments are common…black mudstones

represent anoxic deposition…” (Lawton and Olmstead, 1995, p. 27 and 32).

Extends northwest-southeast across Chiricahua Mountains between Portal and Douglas in

eastern Cochise County.

Partial measured section of 475 ft.

Composite stratigraphic sections are published in Lawton and Olmstead (1995) and

Lawton (2000).

Pennsylvanian DBK shale in Hermosa Group

No geochemical analyses, unknown total organic carbon content (TOC)

“The top of the lower member is a persistent 10 ft bed of black carbonaceous shale”

(McKenny and Masters, 1968, p. 2047).

Named herein for subsurface presence at Dineh-bi-Keyah Field and may be source bed

for oil accumulation in igneous reservoir rock of Oligocene age. The black shale may

extend across northern extent of Defiance uplift in northern Apache County.

Ten ft thick at Dineh-bi-Keyah Field.

Stratigraphic electric-log section showing relationship of black shale to the producing

horizon at Dineh-bi-Keyah is published in McKenny and Masters (1968).

Penetrated by as many as 56 exploration wells in the Dineh-bi-Keyah area. Well logs and

shale sample cuttings are available at the AZGS.

Devonian Elbert/Aneth shales

No geochemical analyses, unknown total organic carbon content (TOC).

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Aneth Formation is known only in the subsurface. It was first described in the Shell No. 1

Bluff Unit in southeastern Utah by Knight and Cooper (1955).

“The Aneth at its type section is composed of dark argillaceous dolomite with thin

interbeds of black shale and dark-colored siltstone” (Parker and Roberts, 1966, p. 2410).

Restricted to northwestern Apache County.

Three to four feet thick at Walker Creek Field.

E-log stratigraphic cross section published in Parker and Roberts (1963 and 1966). E-log

type section published in Harrison (1975).

Penetrated by as many as 83 exploration wells in northeastern Arizona. Typical section is

shown in the Texaco 2 Navajo-AG well in the Walker Creek Field, which produced oil

from the overlying McCracken Sandstone of the Devonian Elbert Formation. Well logs

and Aneth sample cuttings are available at the AZGS.

Devonian Morenci/Portal/Percha shale

No geochemical analyses, unknown total organic carbon content (TOC).

“The upper 30-50 m is an olive-brown to reddish-brown shale called the Morenci

shale…the shale is unfossiliferous, but regional stratigraphic relations suggest it

correlates with the shale member of the Percha formation to the west and with the

[predominantly fissile black] Percha Shale to the east in New Mexico.” (Schumacher,

1978, p. 178). “Member 2 consists of hard, fissile, siliceous black shale that is readily

differentiated from the members above and below by its dark color and complete lack of

carbonate sediments.” (Sabins, 1957, p. 477).

Possible present across most of Graham County and eastern Pima County in southeastern

Arizona.

“Thickness of the shale member ranges from less than 10 ft to more than 200 ft.”

(Schumacher and others, 1976, p. 64).

Generalized columnar and stratigraphic sections are published in Sabins (1957) and

Schumacher and others (1978).

Cambrian Bright Angel Shale

No geochemical analyses, unknown total organic carbon content (TOC).

“The Bright Angel Shale is a mixture of many lithologic types, mostly mudstones, and

fine-grained sandstones, but the dominant rock is a shaley, green mudstone. Some of this

green rock is smooth, micaceous, and fissile; some is covered with fucoidal structures,

and splits along irregular, bumpy surfaces.” (McKee, 1969, p. 80) “Lithologically the

formation consists of sandstone, siltstone, and shale.” (Middleton, 1989, p. 275).

Extends across the Arizona Strip north of Grand Canyon in northwestern Arizona.

“The thickness of the Bright Angel Shale decreases gradually from northwest [402 ft] to

southeast [325 ft].” (Noble, 1922, p. 41-42). “The Bright Angle Shale is over 135 m (445

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ft) thick in the western Grand Canyon, thinning markedly toward the east.” (Middleton,

1989, p. 275).

Stratigraphy of Cambrian rocks exposed in Grand Canyon is published in McKee (1969)

and Middleton (1989).

Penetrated by five exploration wells in northwestern Arizona: Western Drilling/Valen 1

Federal, Brooks Exploration 1-26 Federal, Ultimate 2 Short Creek, Gulf 1 Cordillera 1 BJ

Federal, and Shields 12-24 Federal. Well logs and Bright Angel sample cuttings are

available at the AZGS.

Neoproterozoic Chuar Group, Walcott Shale Member of Kwagunt Formation

Geochemical analyses with good TOC (up to 8.29%) published in AZGS OFR 98-17 and

02-01. “The TOC of 32 samples ranged from 0.07 (poor) to 8.29% (excellent) and

averaged 1.93% (good).” (Wiley and others, 1998, p. 24).

“The thin-bedded, black, highly organic shales, found primarily in thin beds of the

Tanner and Carbon Canyon Members, in the upper portion of the Awatabi Member, and

in most of the Walcott Member, indicate deposition in the dysaerobic to anaerobic water

zones…” (Wiley and others, 2002, p. 49.

Extends from north-central Arizona into south-central Utah and preserved in half graben.

Measured thickness of the Walcott Member ranges from 763 ft to 922 ft (Wiley and

others, 2002, Table 1).

Stratigraphic outline of Grand Canyon Supergroup published in Elston (1989)

Penetrated by at least one exploration well in Arizona: Shields 12-24 Federal. Well logs

and Chuar Group sample cuttings and core chips are available at the AZGS.

Mesoproterozoic Apache Group, Pioneer Shale/black facies of Dripping Springs Quartzite

Geochemical analysis from outcrop samples have good TOC (up to 1.6%) published in

Desborough and others (1984, Table 1, p. 54).

“It is not known if there was sufficient organic-rich material in the black facies of the

Dripping Springs Quartzite and in the upper member of the Mescal Limestone to have

generated and expelled significant volumes of hydrocarbons for migration and economic

accumulation in reservoirs” (Desborough and others, 1984, p. 52).

Extends across most of Gila County in central Arizona.

Black facies of Dripping Springs ranges up to 120 ft thick.

Stratigraphic relations of the Apache Group and a generalized columnar section are

published in Granger and Raup (1964) and Desborough and others (1984).

References cited

Desborough, G.A., Poole, F.G., Daws, T.A., and Scarborough, Robert, 1984, Hydrocarbon

source rock evaluation of the Middle Proterozoic Apache Group, Gila County, Arizona, in

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Woodward, Jane, Meissner, F.F., and Clayton, J.L., eds., Hydrocarbon source rocks of the

greater Rocky Mountain region: Denver, Rocky Mountain Association of Geologists, p. 51-

55.

Dickinson, W.R., Fiorillo, A.R., Hall, D.L., Monreal, R., Potochnik, A.R., and Swift, P.N., 1989,

Cretaceous strata of southern Arizona, in Jenney, J.P., and Reynolds, S.J., eds., Geologic

evolution of Arizona: Arizona Geological Society Digest 17, p. 447-461.

Elston, D.P., 1989, Grand Canyon Supergroup, northern Arizona: Stratigraphic summary and

preliminary paleomagnetic correlations with parts of other North American Proterozoic

successions, in Jenney, J.P., and Reynolds, S.J., eds., Geologic evolution of Arizona: Arizona

Geological Society Digest 17, p. 259-272.

Granger, H.C., and Raup, R.B., 1964, Stratigraphy of the Dripping Spring Quartzite,

southeastern Arizona: U.S. Geological Survey Bulletin 1168, 119 p.

Harding, L.E., and Coney, P.J., 1985, The geology of the McCoy Mountains Formation,

southeastern California and southwestern Arizona: Geological Society of America Bulletin, v.

96, no. 6, p. 755-769.

Harrison, G.C., 1975, Facies analysis of the Devonian in Black Mesa Basin: Flagstaff, Northern

Arizona University, M.S. thesis, 57 p., 1 sheet.

Hayes, M.J., 1987, Depositional history of Upper Cretaceous Fort Crittenden Formation in

southeastern Arizona, in Dickinson, W.R., and Klute, M.A., eds., Mesozoic rocks of southern

Arizona and adjacent areas: Arizona Geological Society Digest, v. 18, p. 315-325.

Hayes, P.T., 1970, Cretaceous paleogeography of southeastern Arizona and adjacent areas: U.S.

Geological Survey Professional Paper 658-B, 42 p.

Inman, K.F., 1987, Depositional environments and sandstone petrography of Cretaceous

sedimentary rocks, Adobe Canyon, Santa Rita Mountains, southeastern Arizona, in

Dickinson, W.R., and Klute, M.A., eds., Mesozoic rocks of southern Arizona and adjacent

areas: Arizona Geological Society Digest, v. 18, p. 301-314.

Knight, R.L., and Cooper, J.R., 1955, Suggested changes in Devonian terminology in the Four

Corners area, in Cooper, J.C., ed., Geology of parts of Paradox, Black Mesa, and San Juan

Basins, Four Corners Field Conference: Four Corners Geological Society Guidebook, p. 56-

58.

Lawton, T.F., 2000, Inversion of Late Jurassic-Early Cretaceous extensional faults of the Bisbee

Basin, southeastern Arizona and southwestern New Mexico, in Lawton, T.F., McMillan, N.J.,

and McLemore, V.T. eds., Southwest passage, a trip through the Phanerozioc: New Mexico

Geological Society 51st Field Conference Guidebook, p. 95-102.

Lawton, T.F., and Olmstead, G.A., 1995, Stratigraphy and structure of the lower part of the

Bisbee Group, northeastern Chiricahua Mountains, Arizona, in Jacques-Ayala, C., Gonzalez-

Leon, C.M., and Roldan-Quintana, J., eds., Studies on the Mesozoic of Sonora and adjacent

areas: Geological Society of America Special Paper 301, p. 21-39.

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McKee, E.D., 1969, Paleozoic rocks of Grand Canyon, in Baars, D.L., ed., Geology and Natural

History of the Grand Canyon region: Four Corners Geological Society 5th Field Conference

Guidebook, p. 78-90.

McKenny, J.W. and Masters, J.A., 1968, Dineh-Bi-Keyah Field, Apache County, Arizona: AAPG

Bulletin, v. 52, no. 10, October, p. 2045-2057.

Middleton, L.T., 1989, Cambrian and Ordovician depositional systems in Arizona, in Jenney,

J.P., and Reynolds, S.J., eds., Geologic evolution of Arizona: Arizona Geological Society

Digest 17, p. 273-286.

Nations, J.D., 1989, Cretaceous history of northeastern and east-central Arizona, in Jenney, J.P.,

and Reynolds, S.J., eds., Geologic evolution of Arizona: Arizona Geological Society Digest

17, p. 435-446

Nations, J.D., Swift, R.L., and Haven, H.W., 2000, Summary of Cretaceous stratigraphy and coal

distribution, Black Mesa Basin, Arizona; Chapter H of Geologic assessment of coal in the

Colorado Plateau, Arizona, Colorado, New Mexico, and Utah: U.S. Geological Survey

Professional Paper 1625-B, 34 p.

Noble, L.F., 1922, A section of the Paleozoic formations of the Grand Canyon at the Bass Trail,

Chap. B, in Shorter contributions to general geology, 1922: U.S. Geological Survey

Professional Paper 131-B, p. 23-73 [published separately as U.S. Geological Survey

Professional Paper 131-B; U.S. Geological Survey Professional Paper 131 published in 1923].

Parker, J.W., and Roberts, J.W., 1963, Devonian and Mississippian stratigraphy of the central

part of the Colorado Plateau, in Bass, R.O., and Sharps, S.L., eds., A symposium: Shelf

carbonates of the Paradox Basin, Fourth Field Conference, June 12-16, 1963: Four Corners

Geological Society, p. 31-61.

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central Colorado Plateau: American Association of Petroleum Geologists Bulletin, v. 50, no.

11, p. 2404-2433.

Rauzi, S., and Spencer, J., 2013, A brief overview of the Cretaceous Mancos Shale in

northeastern Arizona and its hydrocarbon potential: Arizona Geological Survey Open-File

Report 13-08, in review.

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Arizona: American Association of Petroleum Geologists Bulletin, v. 41, no. 3, p. 466-510.

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175-181.

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tectonism in southeastern Arizona, in Wilt, J.C., and Jenney, J.P., eds., Tectonic digest:

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Spencer, J.E., Richard, S.M., Gehrels, G.E., Gleason, J.D., and Dickinson, W.R., 2011, Age and

tectonic setting of the Mesozoic McCoy Mountains Formation in western Arizona, USA:

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Upper Cretaceous upper McCoy Mountains Formation, southwestern Arizona: Geological

Society of America Bulletin, v. 106, no. 4, p. 476-491.

Wiley, B.H., Dehler, C.M., Ghazi, S.A., Kuo, Lung-Chuan, and Rauzi, S.L., 2002, Geologic

description, sampling, and petroleum source rock potential of the Awatubi and Walcott

Members, Kwagunt Formation, Chuar Group of the Sixtymile Canyon section, Grand

Canyon, Arizona: Arizona Geological Survey Open-File Report 02-01, 84 p., 1 sheet.

Wiley, B.H., Rauzi, S.L., Cook, D.A., Clifton, E.H., Kuo, Lung-Chuan, and Moser, J.A., 1998,

Geologic description, sampling, petroleum potential, and depositional environment of the

Chuar Group, Grand Canyon: Arizona Geological Survey Open-File Report 98-17, 92 p., 2

sheets.