Open AccessSublacustrine depositional fans in southwest Melas Chasma
Author(s) -
Metz Joannah M.,
Grotzinger John P.,
Mohrig David,
Milliken Ralph,
Prather Bradford,
Pirmez Carlos,
McEwen Alfred S.,
Weitz Catherine M.
Publication year - 2009
Publication title -
journal of geophysical research: planets
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2009je003365
Subject(s) - sedimentary depositional environment , geology , sinuosity , mars exploration program , paleontology , structural basin , geomorphology , astrobiology , physics
Two depositional fan complexes have been identified on the floor of southwest Melas Chasma. The western fan complex is located near the center of an enclosed basin in southwest Melas Chasma and is composed of multiple lobes with dendritic finger‐like terminations. These fans are very flat and have a morphology unlike any other fan that has been previously identified on Mars. On the basis of the morphologic similarity of the western fan complex to the Mississippi submarine fan complex, we suggest that it may be a deep subaqueous fan depositional system. There are numerous channels on the surface of the western fan complex, and measurements of channel length, width, and sinuosity are consistent with channels observed on terrestrial submarine fans. The eastern Melas depositional fans are less well preserved and may be of deltaic or sublacustrine origin. Recognition of the fans supports earlier suggestions for the presence of a former lake in Melas Chasma and indicates that a significant body of water was present and stable at the surface of Mars for at least 10 2 to 10 4 years.