Investigating Gas Exchange Driven by Mechanochemistry - From Subglacial Ecosystems to the Martian Regolith

We routinely use a variety of Hamilton syringes and needles in the Planetary Science group at Newcastle University dependent on the activity and analytical technique we are employing. The sample lock 1700 series in 250 and 500 μL volumes (part #’s 81156 & 81256 respectively) are ideal for sampling and injections when we conduct gas chromatography analyses (GC-PDD, GC-FID and GC-MS). We also routinely use the larger volume sample lock 1000 series in 5 ml and 10 ml capacity syringes (part #’s 81556 & 81656) when making up standards and for the high accuracy transfer of gasses between different containers.

Our group investigates a diverse range of geological environments by simulating them under laboratory conditions; from the base of glaciers, to the bottom of the sea floor and all the way to the surface of Mars. The theme that links these environments is mechanochemistry. As rocks fracture and fresh surfaces form, radical sites and surface defects are generated. These sites can host unpaired electrons or elemental deficiencies that make these surfaces highly reactive. Reactions with atmospheric gasses, liquids or organic material will often lead to exotic chemistry that we track by analyzing the products.

In subglacial environments the grinding of basal rock units by the massive glaciers above generates these radical sites, members of our group have shown that the production of hydrogen is a sufficient energy source to support ecosystems, a result of great significance for life on land in periods of mass glaciation.

Mars has been cold and dry throughout the geological period known as the Amazonian – covering the last ~ 3 bn years of its history. During this period ice and wind have been the major drivers of erosion. As ‘sand’ blows across the surface of Mars it fractures and generates surface radical sites. One of our most exciting current research areas is the investigation of the reactions this process can drive. The production of oxidants via mechanochemical reactions can help to explain data from missions as far back as the 1970’s NASA Viking landers. With support from the UK Space Agency, the analyses of our laboratory simulations on the effects of mechanochemical reactions with atmospheric gas species and organic material is targeted to interpret data from the imminent ESA rover Rosalind Franklin.