@article{oai:repo.qst.go.jp:00078924,
 author = {丸岡照幸 and 西尾嘉朗 and 小木曽哲 and 鈴木勝彦 and 大澤崇人 and Hatsukawa, Yuuichi and Hatsukawa, Yuuichi},
 issue = {9-10},
 journal = {Geological Society of America Bulletin},
 month = {Feb},
 note = {Chalcophile elements are enriched in the Cretaceous–Paleogene (KPg) boundary clays from Stevns Klint, Denmark. As the concentrations of Cu, Ag, and Pb among several chalcophile elements such as Cu, Zn, Ga, As, Ag, and Pb are correlated with those of Ir, we suggest that these elements were supplied to the oceans by processes related to the endCretaceous asteroid impact. Synchrotron Xray fluorescence images revealed that Cu and Ag exist as trace elements in pyrite grains or as 1–10-µm-sized discrete phases specifically enriched in Cu or Ag. The difference in carrier phases might depend on the materials that transported these elements to the seafloor. Based on their affinities with Cu, Ag, and Ir, iron oxides/hydroxides and organic matter were identified as the potential carrier phases that supplied these elements to the seafloor. Chalcophile elements adsorbed on iron oxides/hydroxides might have been released during reductive dissolution of iron oxides/hydroxides and incorporated into the pyrite produced simultaneously with the reductive dissolution of iron oxides/hydroxides. Both iron oxides/hydroxides and chalcophile elements were possibly released from the KPg target rocks (i.e., sedimentary rocks and/or basement crystalline rocks) by impact heating. Elements with a high affinity to organic matter would have been released upon its degradation and then converted into discrete minerals because of the deficiency in Fe ions.},
 pages = {2055--2066},
 title = {Enrichment of chalcophile elements in seawater accompanying the end-Cretaceous impact event},
 volume = {132},
 year = {2020}
}