Geologic map of the Mare Australe area of Mars

IMAP 1076
By:  and 

Links

Abstract

The south polar region of Mars is among the most geologically diverse on the planet. The areas is within the heavily cratered hemisphere of Mars but is distinguished by a variety of younger, regionally extensive deposits and an assemblage of unique erosional forms. The spectrum of units varies from the oldest to the youngest on the planet. The oldest unit, typifying the cratered hemisphere, is the material of ancient large craters, most of which have undergone advanced degradation. These ancient crater materials are overlain by a variety of regional deposits, including extensive intercrater debris blankets, ridged volcanic flows, and massive eolian deposits that eroded to form complex cliff-rimmed pits. In the central zone of the polar region, south of roughly 75˚ S., these depositional units are, in turn, unconformably overlain by a tremendous sedimentary complex 1,500-2,000 km in diameter, consisting of 40 or more regularly spaced horizontal starta. Each stratum retains apparently uniform thickness (several tons of meters) over hundreds of kilometers; erosional unconformities between starta have not as yet been identified. Resting on the uppermost surface of this layered terrain is the permanent residual polar ice cap. This complex stratigraphic record may ultimately hold the keys to the initial atmospheric evolution, climatological fluctuations, and the history, budget, and mobility of water on the planet.

Publication type Report
Publication Subtype USGS Numbered Series
Title Geologic map of the Mare Australe area of Mars
Series title IMAP
Series number 1076
DOI 10.3133/i1076
Year Published 1978
Language English
Publisher U.S. Geological Survey
Description Report: 2 p.; 1 Plate: 63.22 × 45.88 inches
Other Geospatial Mars
Scale 5000000
Google Analytic Metrics Metrics page
Additional publication details