New Evidence of Water on Mars

Together, these measurements demonstrate that the studied river deposits once filled incised valleys. On Earth, incised valleys are commonly cut and filled during falling and rising eustatic sea level, respectively.

Cardenas and colleagues conclude that similar falling and rising water levels in a large water body forced the formation of the paleo-valleys in their study area. Cross-cutting relationships are observed at the valley-scale, indicating multiple episodes of water level fall and rise, each well over 50 meters, a similar scale to eustatic sea level changes on Earth.

The conclusion that such large water level fluctuations and coastline movements were recorded by these river deposits suggests some long-term stability in the controlling, downstream water body, which would not be expected from catastrophic hydrologic events.

Contacts and sources:
Kea Giles

Citation: Fluvial stratigraphy of valley fills at Aeolis Dorsa, Mars: Evidence for base-level fluctuations controlled by a downstream water body
B.T. Cardenas ([email protected]), D. Mohrig, and T.A. Goudge, Jackson School of Geosciences, University of Texas at Austin, Austin, Texas, USA. Online at https://doi.org/10.1130/B31567.1.