Exploring the Use of Branched Glycerol Dialkyl Glycerol Tetraethers (brGDGTs) as a Lacustrine Paleotemperature Proxy

Monday, 15 December 2014: 9:00 AM
Shannon E Loomis, University of Texas at Austin, Austin, TX, United States, James M Russell, Brown University, Providence, RI, United States and Jaap Sinninghe Damsté,, NIOZ Royal Netherlands Institute for Sea Research, Department of Marine Organic Biogeochemistry, Texel, Netherlands
Paleotemperature reconstructions are crucial for understanding the causes and consequences of past climate change, but quantitative records of terrestrial temperature changes are relatively rare due to the paucity of widely applicable continental paleotemperature proxies. Branched glycerol dialkyl glycerol tetraethers (brGDGTs) have the potential to be a universal terrestrial paleothermometer, as they are found in peat, soil, and lake sediment, and the relative abundances of brGDGTs are correlated to temperature. However, brGDGTs appear to have varying temperature relationships between different sedimentary environments, and the organisms that produce brGDGTs remain elusive, hindering our understanding of seasonality and depth of production of brGDGTs in lakes. Here we explore the environmental controls on brGDGTs in lacustrine environments and evaluate their use as a paleotemperature proxy in different regions of the world.