Carbon Isotopic signatures in Laguna Bacalar, Mexico
Mentor 1
Timothy Grundl
Location
Union Wisconsin Room
Start Date
27-4-2018 1:00 PM
Description
Abstract
Laguna Bacalar is a marl lake in Quintana Roo, Mexico that is actively precipitating large amounts of calcium carbonate. This lake lies within a fault controlled graben and is the second largest lake in Mexico. It also contains the largest occurrence of freshwater stromatolites in the world. There are no surface water inlets to the lake and the water flux is dominated by groundwater. This study will investigate whether the carbon being sequestered in the lake originates from the atmosphere or of it is being transported in by groundwater. If the source is atmospheric the lake is serving as a net sink of atmospheric carbon. The delta13C isotopic signature of carbonate samples collected in the lake will be analyzed to determine if the driving force for precipitation is biogenic precipitation from the atmosphere by stromatolites or abiotic precipitation from the groundwater. Carbonate samples were collected in 2017 and 2018. Both sets of samples will be analyzed for carbon isotopes.
Carbon Isotopic signatures in Laguna Bacalar, Mexico
Union Wisconsin Room
Abstract
Laguna Bacalar is a marl lake in Quintana Roo, Mexico that is actively precipitating large amounts of calcium carbonate. This lake lies within a fault controlled graben and is the second largest lake in Mexico. It also contains the largest occurrence of freshwater stromatolites in the world. There are no surface water inlets to the lake and the water flux is dominated by groundwater. This study will investigate whether the carbon being sequestered in the lake originates from the atmosphere or of it is being transported in by groundwater. If the source is atmospheric the lake is serving as a net sink of atmospheric carbon. The delta13C isotopic signature of carbonate samples collected in the lake will be analyzed to determine if the driving force for precipitation is biogenic precipitation from the atmosphere by stromatolites or abiotic precipitation from the groundwater. Carbonate samples were collected in 2017 and 2018. Both sets of samples will be analyzed for carbon isotopes.
