Post-depositional mobility of platinum, iridium and rhenium in marine sediments

@article{Colodner1992PostdepositionalMO,
  title={Post-depositional mobility of platinum, iridium and rhenium in marine sediments},
  author={Debra C. Colodner and Edward A. Boyle and John M. Edmond and John P. Thomson},
  journal={Nature},
  year={1992},
  volume={358},
  pages={402-404}
}
THE discovery of high concentrations of iridium in Cretaceous/Tertiary boundary sediments engendered the hypothesis1 that a meteorite collided with the Earth 65 million years ago, coincident with the mass extinction that occurred at that time. Iridium spikes of various magnitudes have subsequently been reported at more than 10 other extinction horizons2–11. It has been suggested, on the other hand, that geochemical processes might create or modify many of these spikes5, 11–4, but a critical… 
PLATINUM GROUP ELEMENT ( PGE ) GEOCHEMISTRY OF BRAZOS SECTIONS , TEXAS ,
  • A. U.S.
  • Environmental Science, Geology
  • 2011
Geochemical and sedimentological analyses of platinum group element (PGE) patterns across the Cretaceous–Tertiary (KT) transition of eight sections along the Brazos River, Texas, reveal possible
Extraterrestrial iridium, sediment accumulation and the habitability of the early Earth's surface
We have measured the concentrations of iridium and platinum in ancient metasediments from Akilia Island, southern West Greenland, to obtain the first direct constraints on the extraterrestrial mass
PLATINUM GROUP ELEMENT (PGE) GEOCHEMISTRY OF BRAZOS SECTIONS, TEXAS, U.S.A.
Geochemical and sedimentological analyses of platinum group element (PGE) patterns across the Cretaceous-Tertiary (KT) transition of eight sections along the Brazos River, Texas, reveal possible
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TLDR
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Iridium abundance maxima in the Upper Cenomanian extinction interval
Two iridium abundance peaks, both 0.11 ppb (whole-rock basis) over local background of 0.017 ppb, have been found in Middle Cretaceous marine rocks near Pueblo, Colorado. They occur just below the
Extraterrestrial Cause for the Cretaceous-Tertiary Extinction
TLDR
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TLDR
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Geochemical investigations of a widely dispersed Late Proterozoic impact ejecta horizon and its host shales (Bunyeroo Formation, Australia) have provided strong evidence for low-temperature
Iridium Anomaly Approximately Synchronous with Terminal Eocene Extinctions
TLDR
The iridium anomaly and the tektites and microtektites are supportive of a major bolide impact about 34 million years ago, and other workers have deduced that the microtekkites are part of the North American strewn tektite field, which is dated at about34 million years before present.
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