ORGANIC CARBON-ISOTOPE CHEMOSTRATIGRAPHY FROM THE WHITMORE POINT MEMBER OF THE MOENAVE FORMATION AS AN INDICATOR OF TERRESTRIAL IMPACTS OF THE CENTRAL ATLANTIC MAGMATIC PROVINCE AT THE TRIASSIC – JURASSIC BOUNDARY

Stable isotopic analyses of bulk organic carbon (δ¹³C_org)( collected from lacustrine sediment of the Whitmore Point Member of the Late Triassic to Early Jurassic Moenave Formation in Arizona-Utah, USA) were conducted to develop a carbon isotope curve. Several negative C-isotope excursions that are characteristic of the C-isotope record of the Late Triassic are attributed to the effects of the Central Atlantic Magmatic Province. The C-isotope curve of the Whitmore Point Member will be compared to the global C-isotopic record for the Late Triassic-Early Jurassic to identify evidence of carbon isotope variations associated with the CAMP eruptions and thus the location of the Triassic – Jurassic boundary. Preliminary data ranges between a minimum of -25.44‰ to a maximum of -23.22‰, however, insufficient data has been analyzed to confidently identify any CIEs. Additional data will be analyzed and compared to the coalified wood from the terrestrial Kap Stewart Formation, East Greenland. The coalified wood record from the Kap Stewart shows one negative CIE of -4‰ from the background values. Global correlation of carbon isotopes between marine and terrestrial strata provide a connection between the CAMP basalts and the end Triassic extinction. The CAMP basalts are correlated to the end Triassic extinction and provide an example of how increased CO₂ concentration into the atmosphere can alter the C-cycle, cause extinction, and raise global temperatures. Identification of the negative CIEs associated with the CAMP in the Moenave Formation will help to illustrate the global effects of increased CO₂ on the terrestrial environment.