New Mars Forums

Official discussion forum of The Mars Society and MarsNews.com

You are not logged in.

Announcement

Announcement: As a reader of NewMars forum, we have opportunities for you to assist with technical discussions in several initiatives underway. NewMars needs volunteers with appropriate education, skills, talent, motivation and generosity of spirit as a highly valued member. Write to newmarsmember * gmail.com to tell us about your ability's to help contribute to NewMars and become a registered member.

#1 2017-06-26 07:03:08

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

CO2 traps on Mars

Interesting article.

http://www.lpi.usra.edu/meetings/geomar … f/7044.pdf

Some extracts:
'The recognition of multiple lines of evidence for low geothermal gradients on Mars leads us inexorably to a planet where exceptional conditions are required to bring liquid water to reasonable drilling depths (e.g. 2 km for a light portable and automated drilling rig). Evidence of very recent volcanic activity should be sought to find intrusive centres less than 10^6 years old whole thermal halo has not decayed away.

At the same time, liquid CO2 is thermodynamically stable in the regolith at much shallower depths and models of Mars regolith must recognise the physical and chemical effects of this. Even if only small quantities are present at any one time, over geological time much of the regolith will have been flushed by liquifers of CO2 with its unusual solvent properties.  The existence of liquid CO2 in the regolith represents an important energetic source of vapour for generating cryovolcanic features [6] and major density flows [7]. It also represents a significant drilling hazard in an environment when conventional drilling mud may be precluded due to cryogenic temperatures and to the expectation of severe losses into porous and brecciated regolith.'

This tends to suggest that the crust of Mars may be riddled with pockets of liquid or solid CO2 within as little as 50m from the surface.  Due to the planets unstable axial tilt, large quantities of CO2 may have migrated underground during ice ages and may remain in impermeable traps to this day.

This could be hazardous to drilling, digging and mining on Mars.  It could also provide an obvious source of power for future colonists.  Liquid CO2 could be withdrawn from liquifers, heated above its critical point using stored solar heat and passed through an open cycle gas turbine.  High pressure gas could also be used to power simple compressed air tools, which would be much easier to fabricate on Mars than electrically powered tools.

The implications for terraforming are obvious – much of the Martian atmosphere may exist as trapped liquid or dry ice underground.  However, if terraforming does begin to increase the average temperature of the planet, trapped CO2 could prove hazardous.  A pocket of liquid CO2 could build pressure until it exceeds the structural strength of the impermeable rock containing it.  It would then release energy explosively.  It may be necessary to seismographically detect these deposits and release the pressure before this can happen.

Last edited by Antius (2017-06-26 07:08:13)

Offline

Board footer

Powered by FluxBB