The hydromagnesite playas of Atlin, British Columbia, Canada: A biogeochemical model for CO(2) sequestration

Anthropogenic greenhouse gas emissions may be offset by sequestering carbon dioxide (CO(2)) through the carbonation of magnesium silicate minerals to form magnesium carbonate minerals. The hydromagnesite [Mg(5)(CO(3))(4)(OH)(2)center dot 4H(2)O] playas of Atlin, British Columbia, Canada provide a natural model to examine mineral carbonation on a watershed scale. At near surface conditions, CO(2) is biogeochemically sequestered by microorganisms that are involved in weathering of bedrock and precipitation of carbonate minerals. The purpose of this study was to characterize the weathering regime in a groundwater recharge zone and the depositional environments in the playas in the context of a biogeochemical model for CO(2) sequestration with emphasis on microbial processes that accelerate mineral carbonation