Borchgrevink Glaciers is underlain largely by lavas andhyaloclastites of the McMurdo volcanics, rather than by graniteand Robertson Bay Group, as previously mapped.

Compilations of mapping from this season, along with that ofprevious workers, will permit the production of 12 maps in the1:250,000 Antarctic Geological Reconnaissance Series.

In addition to the scientific program at NVL, the camp hostedseveral distinguished visitors. Stephen Pyne, National Endow-ment for the Humanities Fellow, spent several weeks in campand with field parties chronicling activities, as did Russell Kin-ney, photographer for the National Science Foundation.

Support for the first two authors was provided by NationalScience Foundation grant 1wr 80-19991 to Arizona StateUniversity.

ReferencesGair, H. S., Sturm, A., Carryer, S. J., and Grindley, C. W. 1969. The

geology of northern Victoria Land (Folio 12, Plate 12). In V. C. Bushnell(Ed.), Geologic maps of Antarctica 1:100,000, Antarctic maps folio series.New York: American Geographical Society.

Splettstoesser, J . F., and Turner, M. D. 1982. Logistics as related to UnitedStates geologic field programs in Antarctica. Paper presented at theFourth International Symposium on Antarctic Earth Sciences, 15-21August 1982, University of Adelaide, Adelaide, Australia.

Splettstoesser, J . F., and Webers, C. F 1980. Geological investigationsand logistics in the Ellsworth Mountains, 1979-80. Antarctic Journal ofthe U.S., 15(5), 36-39.

Splettstoesser, J. F, Webers, C. F., and Waidrip, D. B. 1982. Logisticaspects of geological studies in the Ellsworth Mountains, Antarctica,1979-80. Polar Record, 21(131), 147-159.

Study of radloelement concentrationsin northern Victoria Land by gamma-

ray spectrometry

GISELA A. M. DRESCHHOFF and EDWARD J . ZELLER

Space Technology CenterUniversity of Kansas

Lawrence, Kansas 66045

WOLF-RUDIGER KROPP

Bundesanstalt für Geowissenschaften und RohstoffeHannover, West Germany

During the 1981-82 field season we conducted airborne radi-ometric survey operations from the remote camp near theFreyberg Mountains in northern Victoria Land. Survey opera-tions began on 20 December 1981, and a total of 3,260 kilometersof flight line was completed during the season. In addition, wemade test flights to calibrate the counter for Compton scatteringand attenuation with variable ground clearance. Upon return toMcMurdo Station, we made a similar calibration in Taylor Valley.Finally, we emplaced a series of solid state radiation dosimetersat several locations in the Ross Island volcanics. These rocks areknown to be unusually high in radioelement concentration(Zeller et al. 1982). The dosimeters will be recovered after 1 yearand will furnish the basis for a feasibility test of this method formeasuring the geologic radiation environment.

The results of the northern Victoria Land survey have alreadybeen evaluated, and they have proved to be especially interest-ing. The average radioactivity of the rocks exposed in northernVictoria Land is roughly twice the level of outcrop radioactivityin the Darwin Glacier area. While this undoubtedly is related inpart to differences in the geology of these widely separatedportions of the Transantarctic Mountains, it also may reflect

fundamental differences in the crustal abundance of theradioelements.

To facilitate data interpretation, the survey area was dividedinto two major districts separated by the Rennick Glacier andthe major fault that parallels its eastern margin. The division isbased on the general geology of northern Victoria Land. Signifi-cant differences characterize the two districts (Dreschhoff,Zeller, and Kropp 1982). The figure shows the area surveyedand provides a graphic summary of the results. The data arereported as relative values by relating all individual radioele-ment concentrations to the corresponding mean concentrationfor the entire survey area. The two bar graphs represent themaximum relative values for the largest anomalies of uranium,thorium, and potassium in the individual districts and are de-rived by averaging the points that exceed two standard devia-tions from the mean for the entire area. The shaded length ofthe bar represents the relative mean for the entire area.

The northeastern district shows mainly concentrations ofthorium but little anomalous enrichment of uranium. In con-trast, the southwestern district exhibits anomalous con-centrations of all three radioactive elements, and most of theanomalies are associated with the Granite Harbor Intrusives orthe Kukri Erosion Surface where it cuts the Granite Harborplutons. One of the strongest anomalies occurs at the top ofMount Bower in the Outback Nunataks where a remnant of theBeacon Group resting on the Kukri Erosion Surface is pre-served. A landing was made, but high winds prevented a thor-ough evaluation of the outcrop. However, the thorium-to-ura-nium ratio indicates that geochemical separation of theseelements has occurred and that uranium enrichment has takenplace. Although it is unlikely that any substantial uraniummineralization is present at Mount Bower, this occurrence con-firms our previous evidence that the Kukri Erosion Surface andthe adjacent rocks offer the greatest promise for uranium re-sources (Zeller and Dreschhoff in press). We believe that theregion adjoining the survey area to the south and west shouldbe examined for potential sedimentary uranium concentrationsin the basal Beacon Group sediments.

This project is a continuing effort of the University of Kansasand the West German Federal Institute of Geosciences and

4 ANTARCTIC JOURNAL

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Map showing survey area in northern Victoria Land and graphic summary of results. U = uranium; Th = thorium; K = potassium.

Resources. The research was supported in part by Nationaltional Symposium on Antarctic Earth Sciences, 15-21 August 1982,Science Foundation grant DPP 77-21504. University of Adelaide, Adelaide, Australia.

Zeller, E. J. , and Dreschhoff, C. A. M. In press. Uranium resourceevaluation in Antarctica. In J. Splettstoesser (Ed.), Mineral resource

References potential of Antarctica. Austin: University of Texas Press.Zeller, E. J. , Dreschhoff, C. A. M., Crisler, K., and Tessensohn, F. 1982.

Dreschhoff, G. A. M., Zeller, E. J . , and Kropp, W. R. 1982. RadiometricResource and radioactivity survey in Antarctica. In C. Craddock

survey in northern Victoria Land. Paper presented at the Fourth Interna-(Ed.), Antarctic geoscience. Madison: University of Wisconsin Press.

1982 REVIEW 5