Home / Node / Briony Horgan Colloquium Abstract (Oct 12, 2016)

Briony Horgan Colloquium Abstract (Oct 12, 2016)

Mineral signatures of glacial environments and implications for past climates on Mars

Observations of widespread rivers and lakes on early Mars have been interpreted as indicating that the martian climate was once warmer and wetter than it is today. However, climate models suggest that only cold and icy climates are possible on early Mars. One avenue for resolving this paradox may be through chemical indicators of climate, as recorded in the weathering mineralogy of the martian surface. This talk will report on new field studies of glacial weathering in Mars analog volcanic environments in the Oregon Cascade Range. We propose that weathering in climates dominated by snow melt, glacial, and periglacial processes produces distinctive minerals compared to weathering in warmer climates. While cold climates could be responsible for some of the minerals we find on Mars, it probably cannot explain the diversity of minerals identified by satellites and rovers on Mars, suggesting that ancient Mars experienced both cold and more temperate climates.

Talk slides (PDF)

Technical Talk:

The habitability of Mars over time and implications for Mars2020 rover landing site selection

The mission of NASA's upcoming Mars2020 rover is to seek out signs of life on ancient Mars, and to collect samples for eventual return to Earth. The Mars science community is currently considering where on Mars the 2020 rover should land, and proposed landing sites include a diverse suite of environments spanning nearly one billion years of martian geologic history. However, the habitability of ancient martian environments likely changed significantly over this time period. This talk will discuss the rationale behind the proposed 2020 landing sites and their context within the martian geologic record.

Technical talk abstract (PDF)