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Backstripping the Chesapeake Bay Impact Structure

其他書名	Differentiating Regional Tectonics from Impact Effects
出版	Western Michigan University, 2008
URL	http://books.google.com.hk/books?id=_gJdPgAACAAJ&hl=&source=gbs_api

註釋The Chesapeake Bay impact structure is a ca. 35.4 Ma old crater located on the coastal plain of Virginia along the eastern seaboard of North America. The impact generated a crater between 85 and 90 km in diameter, and over 2000 meters deep. Deposition returned to normal shortly after impact, resulting in a unique record of both the impact related and subsequent passive margin sedimentation. We use backstripping to show that the impact strongly affected sedimentation for 7 m.y. through a combination of impact derived crustal scale tectonics, dominated by the introduction and subsequent removal of a negative thermal anomaly, and the effects of sediment compaction and. This is contrary to the positive thermal anomaly that was hypothesized to be generated by an impact event. After the effects of the impact ceased, the area was dominated by passive margin thermal subsidence, which was overprinted by periods of regional scale vertical tectonic events. These regional scale non-thermal tectonics were on the order of 10's of meters and may have been caused by loading due to prograding sediment bodies.