@inbook{77,
  author = {T. Adatte and G. Keller and S. Burns and K. Stoykova and M. Ivanov and D. Vangelov and Utz Kramar and Doris St{\"u}ben},
  title = {Paleoenvironment across the Cretaceous-Tertiary transition in eastern Bulgaria},
  abstract = {<p>The Cretaceous-Tertiary (K-T) transition in eastern Bulgaria (Bjala) was analyzed in terms of lithology, mineralogy, stable isotopes, trace elements, and planktic foraminifera. The sequence represents a boreal-Tethyan transitional setting, spans from the last 300 k.y. of the Maastrichtian (zone CF1) through the early Danian (zones P0-Plc), and contains several short hiatuses. It differs from low-latitude Tethyan sequences primarily by lower diversity assemblages, pre-K-T faunal changes, a reduced K-T δ<sup>13</sup>C shift, and the presence of two clay layers with platinum group element anomalies. The first clay layer marks the K-T boundary impact event, as indicated by an iridium anomaly (6.1 ppb), the mass extinction of tropical and subtropical planktic foraminifera, and cooling. The second clay layer is stratigraphically within the upper Parvularugoglobigerina eugubina (Pla) zone and contains a small Ir enrichment (0.22 ppb), a major Pd enrichment (1.34 ppb), and anomalies in Ru (0.30 ppb) and Rh (0.13 ppb) that suggest a volcanic source.\&nbsp; <a href="https://geoweb.princeton.edu/research/keller/pubs/Adatte_et_al_GSA_spec_Paper_2002.pdf" target="_blank">PDF</a></p>
},
  year = {2002},
  journal = {Catastrophic Events and Mass Extinctions: Impacts and Beyond: Boulder, Colorado},
  publisher = {Geological Society of America Special Paper 356},
  address = {Boulder},
  language = {eng},
}