The Bug Creek Problem and the Cretaceous-Tertiary Transition at McGuire Creek, Montana 在線電子書 圖書標籤:
發表於2024-11-30
The Bug Creek Problem and the Cretaceous-Tertiary Transition at McGuire Creek, Montana 在線電子書 pdf 下載 txt下載 epub 下載 mobi 下載 2024
Bug Creek assemblages from Montana, transitional in composition between typical Cretaceous and Paleocene vertebrate faunas, are critical to K-T extinction debates because they have been used to support both gradual and catastrophic K-T extinction scenarios. Geological and palynological data from McGuire Creek indicate that Bug Creek assemblages are Paleocene and restricted to channel fills entrenched into older sediments, suggesting that the Cretaceous component of the assemblage was reworked. Thus, the author concludes, "Paleocene dinosaurs" are an illusion and the K-T survival rate of mammals is low because the presence of Cretaceous mammals in Bug Creek assemblages is also the result of reworking.
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The Bug Creek Problem and the Cretaceous-Tertiary Transition at McGuire Creek, Montana 在線電子書 pdf 下載 txt下載 epub 下載 mobi 下載 2024