Leonard David's INSIDE OUTER SPACE

Distribution of the studied basins on Mars based on Mars Orbiter Laser Altimeter topography (blue indicates high elevations).
Credit: Salese et al.

New research points to geological evidence supporting a planet‐wide groundwater upwelling on Mars.

This newly recognized evidence of water‐formed features significantly increases the chance that biosignatures could be buried in the sediment. These deep basins (groundwater‐fed lakes) will be of interest to future exploration missions as they might provide evidence of geological conditions suitable for life.

These views are contained in the paper — Geological Evidence of Planet‐Wide Groundwater System on Mars – published in the American Geophysical Union’s Journal of Geophysical Research: Planets.

Conceptual model, of Martian basins evolution and their relations with the groundwater storage, from the oldest (bottom) to the most recent stage (top).
Credit: Salese et al.

Deep closed basins

Most previous studies on Mars relevant groundwater have proposed models, but few have looked at the geological evidence of groundwater upwelling in deep closed basins in the northern hemisphere equatorial region, the paper explains.

Observations in the northern hemisphere show evidence of a planet‐wide groundwater system on Mars.

The elevations of these water‐related morphologies in all studied basins lie within the same narrow range of depths below Mars datum and notably coincide with the elevation of some ocean shorelines proposed by previous authors. The term called “Mars datum surface” refers to the average elevation on Mars.

Morphologies inside Crater #9. A large stepped delta can be observed on the northeast side of the crater. Possible shoreline indicated at −4,200 m (maroon arrows).
Credit: Salese et al.

Interconnected?

The research, led by Francesco Salese of the Faculty of Geosciences, Utrecht University, Utrecht, The Netherlands suggests that subsurface aquifers in all basins might be interconnected.

“Nevertheless, the evidence obtained from this work is not enough to affirm with certainty the interbasins connection,” Salese and colleagues explain. “Our observations show that the extent of this aquifer is very significant and it leads us to support the thesis that it could have been planet wide.”

To review the paper — Geological Evidence of Planet‐Wide Groundwater System on Mars – go to:

https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2018JE005802