Sanidine spherules at the Cretaceous–Tertiary boundary indicate a large impact event
@article{Smit1981SanidineSA, title={Sanidine spherules at the Cretaceous–Tertiary boundary indicate a large impact event}, author={Jan Smit and Gerard Th. Klaver}, journal={Nature}, year={1981}, volume={292}, pages={47-49} }
The hypothesis that a catastrophic impact of an extraterrestrial body caused the terminal Cretaceous mass extinctions of dinosaurs, planktonic foraminfera and other species is now accepted as respectable following the discovery of a worldwide iridium enrichment in the Cretaceous–Tertiary (K–T) boundary clay1–5. In the basal lamina of the K–T boundary clay of Caravaca (Spain)7 numerous spherules were discovered composed of finely crystallized, almost pure K-feldspar in the structural state of…
174 Citations
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