SPS Seminar - Effect of the low-pressure conditions to mud behavior: Insights from laboratory experiments - implications for mud volcanism on Mars

When:  Thursday 3^rd March at 14.00

Where:  Microsoft Teams - Online

Speaker:  Dr. Ondřej Krýza (Institute of Geophysics of the Czech Academy of Sciences)

Hosted by: Alexander Barrett

Abstract:

The behavior and the rheology of mud during the emplacement of terrestrial sedimentary volcanism is broadly studied and well understood. In contrast, this is not the case for Mars nor for other planetary bodies within the Solar System when this kind of volcanism could exist as several recent studies suggest.

The first experiments in the Large Mars Chamber (HVIlab at the Open University in UK) revealed that the mud released on cold and hot surfaces in a low-pressure environment (6-7 mbar) propagates in a highly contrasting manner. In touch with the hot surface, the mud which is boiling in a pressure below ~20 mbar, has potential to ‘levitate’ as material particles are pushed by reaction due to the vapor escape. When mud touches the cold surface, it immediately starts to freeze and forms a series of inflating mud lobes and channels similar to the Pahoehoe lava flows formed in Earth conditions.

In the new sets of experiments, we tested the potential of these muds to inflate due to formation of bubbles and their movement through mud bulk. The preliminary results show how this is strongly dependent on viscosity and partly on density of mud as a whole process depends on the drag forces. The mud propagation itself is then also driven by proportional content of clay particles, water, and dissolved salts. This results in various viscosities and also drives freezing ability. Thus, the style of mud flowing over the cold surfaces occurs in a development of various morphologies and moreover in a potential thermal erosion of the surface of Mars.

Bio:

Dr. Ondřej Krýza works at the Institute of Petrology and Structural Geology at Charles University in Prague. He has a background in both physics and structural geology. He completed his masters in 2013 and a Ph.D. in 2020, exploring numerical simulations of geodynamical systems. He is presently visiting the OU, using the Large Mars chamber to simulate mud flows on Mars.