HR: 1340h
AN: P23B-0187    [Abstracts]
TI: Stability and evolution of ice cored glacial deposits on the flanks of volcanoes
AU: * Helbert, J
EM: joern.helbert@dlr.de
AF: Institute of Planetary Research - DLR, Rutherfordstrasse 2, Berlin, 12489 Germany
AU: Reiss, D
EM: dennis.reiss@dlr.de
AF: Institute of Planetary Research - DLR, Rutherfordstrasse 2, Berlin, 12489 Germany
AU: Breuer, D
EM: doris.breuer@dlr.de
AF: Institute of Planetary Research - DLR, Rutherfordstrasse 2, Berlin, 12489 Germany
AB: There are several units on Mars which have been interpreted as glacial deposits based on morphological evidences. Many of these units are found on the flanks of volcanic edifices. Especially the recent imaging by the HRSC camera on Mars Express has provided us with a wealth of new examples and with much more morphological details. These include deposits as young as 5-14 Ma for example on the flanks of Hecates Tholus. We have recently studied this deposit and found a high likelihood that it is still ice cored. Based on our cautious estimates this ice would be protected by an only 10-50m thick sublimation till. We will report more detailed on these findings and compare it with comparable deposits at the flanks of other volcanoes. This deposit is especially interesting because there are indications for very recent activity of Hecates Tholus, including lava flows potentially as young as 2Ma. Assuming that we are today in a quieter but still active phase of the volcano we will discuss the implications for the internal structure and especially the redistribution of ice in such a deposit assuming episodic changes in the internal heat flow. There are indications for the formation of ice lenses potentially sealing environments at the base of this and similar deposits on other volcanic edifices. There is a wide variety of implications ranging from storage and delayed release of volcanic gases (incl. methane) up to potentially forming niches for biological activities.
DE: 5220 Hydrothermal systems and weathering on other planets
DE: 5416 Glaciation
DE: 5418 Heat flow
DE: 5422 Ices
DE: 5480 Volcanism (6063, 8148, 8450)
SC: Planetary Sciences [P]
MN: Fall Meeting 2005