Nebraska Academy of Sciences
Date of this Version
1978
Document Type
Article
Abstract
The stratigraphic record of the Antarctic continent records a history compatible and comparable with that of any of the other continents: a Pre-Cambrian basement truncated by a major erosion surface, a sequence of Paleozoic and Mesozoic sediments, and finally a Cenozoic record dominated by glacial deposits. Two major geologic provinces are recognized: East Antarctica, a typical continental shield or stable platform consisting of older igneous and metamorphic rocks overlain by younger, mainly flat-lying stratified sedimentary and igneous rocks; West Antarctica is composed mainly of younger rocks that are deformed and metamorphosed-abundant intrusive and extrusive rocks are present and volcanic activity continues in some areas.
The Pre-Cenozoic stratigraphic record must be carefully studied before making any guesses as to climatic change. It is necessary to recognize the fact that the stratigraphic record at a given locality may yield temperature information that could be grossly misleading if interpreted as a record of worldwide climatic change. Localized glacial deposits may reflect only a topographic effect, not a worldwide climatic change, and the differences between the features characteristic of hot or cold deserts are not well understood. A second confusion factor is the geographic location. The recent "revolution in earth sciences" and the general acceptance of the mobility of continents make it difficult to interpret the ancient record. If We assume no major shifts in the axis of rotation, etc., then one might well expect a record of a cold climate in deposits formed in polar regions. What becomes difficult is the reconstruction of the paleogeography to allow one to make paleo-climatic inferences.
Comments
Transactions of the Nebraska Academy of Sciences- Volume VI, 1978. Copyright © 1978 Rutford