A Dual-layer Chicxulub Ejecta Sequence with Shocked Carbonates from the Cretaceous-tertiary (k/t) Boundary, Odp Leg 207, Western Atlantic
نویسندگان
چکیده
Introduction: An up to 2-cm thick Chicxulub ejecta deposit marking the Cretaceous-Tertiary (K/T) boundary (Fig. 1) was recovered in 6 holes drilled during ODP Leg 207 (Demerara Rise, tropical western Atlantic [1-3]). High-resolution mineralogical, petrological, and elemental data reveal a distinct microstratigraphy and a range of ejecta components. Prominent features are the uniformity of this deposit over an area of 30 km2, the absence of bioturbation, allowing documentation of the original sedimentary sequence, and the presence of calcite and dolomite clasts next to shocked tectosilicates in the topmost millimeters. These carbonate clasts show in part exotic features obviously related to the Chicxulub impact event.
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