Ismenius Cavus, Mars: A deep paleolake with phyllosilicate deposits
- Research areas:
- Year:
- 2010
- Authors:
- Journal:
- PLANETARY AND SPACE SCIENCE
- Volume:
- 58
- Number:
- 6
- Pages:
- 941-946
- Month:
- May
- ISSN:
- 0032-0633
- Abstract:
- Ismenius Cavus is a basin where several fluvial valleys converge. Three
depositional fan deltas are observed at the valleys outlets at similar
elevations. These fans suggest long-term fluvial activity accompanied by
a lake inside the basin. The elevational difference between the delta
plains and the deepest part of the basin floor implies that this lake
was 600 m deep. Iron-magnesium phyllosilicates, which are mapped from
near-infrared spectral data, are associated with layered sediments > 300
m thick at the base of one of the fans. Stratigraphic relationships with
the surrounding plateau show that the valleys are hesperian in age
(3.0-3.7 ga), thus dating the lake activity to this period. The
coexistence of a deep lake and phyllosilicates demonstrates that
persistent bodies of liquid water were present during the hesperian
period. (C) 2010 Elsevier Ltd. All rights reserved.
