General Geology of the Mount Weaver Area, Queen Maud Mountains, Antarctica
- Jarvis B. Hadley
Published Online: 3 APR 2013
Copyright © 1965 by the American Geophysical Union.
Geology and Paleontology of the Antarctic
How to Cite
Doumani, G. A. and Minshew, V. H. (1965) General Geology of the Mount Weaver Area, Queen Maud Mountains, Antarctica, in Geology and Paleontology of the Antarctic (ed J. B. Hadley), American Geophysical Union, Washington, D. C.. doi: 10.1029/AR006p0127
- Published Online: 3 APR 2013
- Published Print: 1 JAN 1965
Print ISBN: 9781118655733
Online ISBN: 9781118668528
- Age and regional correlations;
- Diabase intrusives;
- Mount weaver area;
- Queen maud mountains;
- Sedimentary rocks;
- Volcanic rocks
The rocks exposed in the Mount Weaver area are chiefly granitic and sedimentary, with diabase sills and less extensive volcanic, metamorphic, and glacial deposits. Characteristic of the gray granite are abundant xenoliths of schist and gneiss and numerous veins of pegmatite. The sedimentary section, nonconformably overlying the granite on an undulating erosional surface, comprises a basal conglomerate, intercalated beds of sandstone, shale, and coal, and a related tillite. A ‘Glossopteris flora’ is represented by abundant Glossopteris leaves and fossil trees, probably of Dadoxylon and Antarcticoxylon wood, some of them in upright position. The assemblage is indicative of climatic conditions conducive to the prolific growth of luxuriant vegetation. The sandstones are massive to thin-bedded and exhibit animal burrows and trails. Black shales near the bottom of the section are highly carbonaceous and contain abundant limy lentils, concretions, and cone-in-cone structures. Diabase sills intrude the sedimentary strata at several levels from the basement to the top of the section. The sills are probably contemporaneous with diabase intrusives in other parts of the Transantarctic Mountains. Field observations suggest that the direction of sill intrusion is from northwest to southeast.
Two types of tillite were found, one as erratics and the other in situ. The former, which is similar to the Buckeye Tillite of the Ohio Range 150 miles to the northeast, might have been transported from a source west of the Robert Scott Glacier. The tillite in situ is markedly different and contains diabase boulders. If the boulders were derived from the sills, this tillitc is probably Jurassic or younger. Metamorphic rocks that crop out on the east side of the Robert Scott Glacier are composed of green chloritic slate, quartzite, and phyllite and are probably older than the granites. The youngest rocks in this region, volcanics, were seen in two places north and south of Mount Weaver. They are predominantly black, scoriaceous, olivine basalt, with minor amounts of yellow tuff and tuff breccia.
The stratigraphic sequence, general characteristics of the rocks, and geologic events of the Mount Weaver area appear to be similar to those of the Ohio Range and of the other Upper Paleozoic deposits in the southern hemisphere; direct correlation is not feasible at present, however.