@inbook{38,
  keywords = {Iridium, PGE, K-T boundary, Brazos River, Texas},
  author = {B. Gertsch and G. Keller and T. Adatte and D. Bartels},
  title = {Platinum Group Element (PGE) Geochemistry of Brazos Sections, Texas, U.S.A.},
  abstract = {<p>Geochemical and sedimentological analyses of Platinum Group Element (PGE) patterns across the Cretaceous/Tertiary (K-T) transition of 8 sections along the Brazos River, Texas, reveal possible sources and processes responsible for PGE enrichments. Of the five global KT boundary-defining characteristics (mass extinction in planktic foraminifera, first appearance of Danian species, negative δ<sup>13</sup>C excursion, Ir anomaly, thin (0.5 cm) red clay layer), the Ir anomaly and red clay layer are not present at the KTB in the Brazos sections. Instead, PGEs and especially Ir show several minor enrichments within the sandstone complex with the largest peak at the top or just above it. Possible mechanisms of PGE enrichments include, low sedimentation rates or sediment starvation that concentrates Ir and other PGEs. Absence of Ir at the KTB is likely linked to dilution effects caused by high sedimentation rates, and other still unknown processes. The source of PGEs remains elusive, but may be linked to an increased input of extraterrestrial dust during the late Maastrichtian, or reworked PGEs from the Chicxulub impact that predates the KTB in these sections.\&nbsp; <a href="https://geoweb.princeton.edu/research/keller/pubs/Gertsch_et_al_2011_SEPM-100.pdf" target="_blank">PDF</a></p>
},
  year = {2011},
  journal = {The End-Cretaceous Mass Extinction and the Chicxulub Impact in Texas},
  volume = {No. 100},
  edition = {SEPM, Special Publication},
  pages = {227-249},
  publisher = {SEPM (Society for Sedimentary Geology)},
  address = {Tulsa},
  issn = {978-1-56576-308-1},
  language = {eng},
}