THE PRISTINE CHICXULUB EJECTA SEQUENCE AT ODP Leg 207: A MICRO-CHEMICAL STUDY
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چکیده
Introduction: The discovery of high concentrations of platinum group elements (PGEs) in the uppermost clay-rich sediments of the Cretaceous (K) was the key to link the mass extinction at the CretaceousPaleogene (“K/T”) boundary to the impact of a large extraterrestrial projectile, now known to have formed the Chicxulub crater [1]. The true nature of this “Iridium anomaly” as well as of other striking features (e.g., presence of unusual carbonate clasts, various geo-
منابع مشابه
A Dual-layer Chicxulub Ejecta Sequence with Shocked Carbonates from the Cretaceous-tertiary (k/t) Boundary, Odp Leg 207, Western Atlantic
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 ...
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