Applicability of the TEX86 Paleotemperature Proxy on the Peterborough Member of the Oxford Clay Formation

Jurassic sea surface temperature is often estimated using the stable isotope compositions of carbonate and phosphatic fossils. However, in instances when these fossils are not available, organic proxies have become increasingly employed. The TEX86 is an organic paleotemperature proxy based on the relative abundance of isoprenoid glycerol dialkyl glycerol tetraethers. The TEX86 record is extensive for Cenozoic and Cretaceous sediment but become sparce in the Jurassic. Here, the TEX86 is applied for the first time to the mid-Jurassic on seven Callovian black shale samples from the Peterborough Member of the Oxford Clay Formation in central England. Glycerol dialkyl glycerol tetraethers were detectable in every sample, however, all samples but one, a Gryphaea Shell Bed biofacies, were observed to provide TEX86 data compromised by non-thermal processes. The calculated sea surface temperature was observed to agree with previous paleotemperature reconstruction research on the Oxford Clay Formation using oxygen isotopes. This data suggests that the TEX86 is applicable to the Oxford Clay Formation if oxygenated samples are used.