Recent tectonics and subsidence on Mars: Hints from Aureum Chaos

SPAGNUOLO, M. G.; ROSSI, ANGELO P.; HAUBER E.; VAN GASSELT S.

EARTH AND PLANETARY SCIENCE LETTERS

ELSEVIER SCIENCE BV

Año: 2011 vol. 312 p. 13 - 21

0012-821X

High spatial and spectral resolution imagery and topography collected during the last decade are changing ourvision of Mars into that of a geologically active planet, even in recent times. However, the connection betweeninternal activity such as faulting and other recent geomorphic processes and deposits, such as eolian or masswasting units, is difficult to establish. In this work we study a geomorphic feature located inside AureumChaos (4°S, 333°E) which is situated at the dichotomy boundary between southern highlands and northern lowlandsonMars.Weidentified fault-related activity based on HIRISE imagery and mapped a landslide of LTD (LightTone Deposits) material which seems to be modified by a fault. Displacement measurements across the scarp arein agreement with values measured in other Amazonian-aged extensional settings on Mars. Moreover, the relationbetween landslide and eolian material shows that it was produced very recently in time, since the activityseems to postdate a dune field whose age was determined to be less than 1.9 Myr old. This observation togetherwith other scarp-related activity near the area suggests that very recent subsidence activity has occurred alongprevious fault planes inside Aureum Chaos.