Faunal, erosional, and CaCO3 events in the early Tertiary eastern Tethys

TitleFaunal, erosional, and CaCO3 events in the early Tertiary eastern Tethys
Publication TypeBook Chapter
Year of Publication1990
AuthorsKeller, G, Benjamini, C, Magaritz, M, Moshkovitz, S
Book TitleGeological Society of America Special Papers
PublisherGeological Society of America

The early Paleocene up to the initial establishment of stable oceanographie conditions after the K/T boundary event is examined in the eastern Tethys based on stratigraphie, faunal, CaCO3, and δ18O isotope analyses. The earliest Paleocene is characterized by redeposited and bioturbated sediments containing abundant reworked Cretaceous foraminifers and nannofossils mixed in with a characteristic basal Tertiary assemblage. Widespread hiatuses are identified in this interval based on abrupt truncation of dominant species and outcrop observations: at the K/T boundary, the P0/P1a boundary, and at the Pla/Plb boundary. Species diversity increases rapidly above this interval. These faunal changes are accompanied by decreasing CaCO3 accumulation interrupted by three major negative excursions: at the K/T boundary, in Subzone P1b, and at the P1b/P1c boundary coincident with deposition of a black organic-rich clay layer and the decline and eventual extinction of the dominant Cretaceous survivor Guembelitria. Stable-carbonate deposition began in foraminiferal Subzone P1c and the nannofossil NP1/NP2 Zone boundary about 400,000 years after the K/T boundary event, correlative with initial stabilization of foraminiferal assemblages as indicated by relatively stable species populations.   PDF

Original PublicationIn, Global Catastrophes in Earth History, Snowbird II