Physics
Scientific paper
Dec 2008
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008agufm.p43b1401l&link_type=abstract
American Geophysical Union, Fall Meeting 2008, abstract #P43B-1401
Physics
0710 Periglacial Processes, 1041 Stable Isotope Geochemistry (0454, 4870), 1830 Groundwater/Surface Water Interaction, 5462 Polar Regions, 6225 Mars
Scientific paper
Near Eagle Plains, northern Yukon, acidic Ca-Fe-Mg-SO4 waters are discharging year-long from disturbed permafrosted sandstone bedrock overlying pyritiferous shales. The acidic waters are also precipitating gypsum with minor amounts of jarosite-K (Na), schwertmannite and hematite, similar to the mineral sequence observed at Meridiani Planum, making this site a valuable analogue for low temperature sulfate geochemistry and mineral formations on Mars. Stable O-S isotope analysis of the acidic waters near Eagle Plains revealed that the oxygen in the dissolved sulfate was mostly derived from water, suggesting that the sulfide oxidation process could be in part biomediated (i.e., accelerated by Fe-oxidizing microorganisms). However, unlike the dissolved sulfate in the waters, the formation of the Ca-Fe sulfate minerals is abiotic. The stable O-S isotope composition of the sulfate minerals is well within the predicted equilibrium range, suggesting that they formed through physico-chemical processes (i.e., evaporation or freezing). Low temperature geochemical modeling with FREZCHEM and PHREEQC suggests that the mineral sequence at Eagle Plains formed through the freezing of Ca-Fe-Mg-SO4 waters, rather than through evaporation during the dry summer season. Although the later is still a valid process of sulfate mineral formation at Eagle Plains as the acidic stream nearly dries-up during the summer. Overall, the fact that acid drainage is presently active allows to directly observe the low temperature (bio)geochemical processes responsible for generating acid drainage and precipitation of gypsum, schwertmannite, jarosite-K, jarosite-Na, goethite and hematite.
Lacelle Denis
Léveillé Richard
Mader Matthias
No associations
LandOfFree
Acid Drainage Generation and Associated Ca-Fe-SO4 Minerals Near Eagle Plains, Northern Yukon: an Analogue for Low Temperature Sulfate Formation on Mars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Acid Drainage Generation and Associated Ca-Fe-SO4 Minerals Near Eagle Plains, Northern Yukon: an Analogue for Low Temperature Sulfate Formation on Mars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Acid Drainage Generation and Associated Ca-Fe-SO4 Minerals Near Eagle Plains, Northern Yukon: an Analogue for Low Temperature Sulfate Formation on Mars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1238607