Chesapeake Bay impact crater

The Chesapeake Bay impact crater is what remains of a 35 million year old meteorite strike at the mouth of the Bay and the Atlantic Ocean. The impactor blasted through water and sediment and into the continental shelf's granite rock, blowing pieces of earth hundreds of kilometers away. Some estimates measure the crater at about 40 kilometers wide and 1.3 kilometers deep. Under ground, the impact broke up local aquifers, and created a depression that still contributes to some of the sinking of land in the Bay. [1, 2, 3]

While drilling at the site, researchers have found a buried body of seawater more ancient than the crater, perhaps 100 to 145 million years old. [5, 6, 7]

Notes

1. "The impact crater", US Geological Survey, [ meteor.pwnet.org/impact_event/impact_crater.htm ], accessed 2013-07-05.

2. "Chesapeake Bay crater offers clues to ancient cataclysm" by Hillary Mayell for National Geographic News, 2001-11-13, [ news.nationalgeographic.com/news/2001/11/1113_chesapeakcrater.html ], accessed 2013-07-05.

3. "Chesapeake Bay impact crater" article in Wikipedia, [ en.wikipedia.org/wiki/Chesapeake_Bay_impact_crater ], accessed 2013-07-05.

4. "Seismic expression of the Chesapeake Bay impact crater: structural and morphologic refinements based on new seismic data" by C. Wylie Poag, Deborah R. Hutchinson, and Steven M. Colman and Myung W. Lee, Geological Society of America, 1999, [ books.google.com/books ], accessed 2013-07-05.

5. "Evidence for high salinity of Early Cretaceous sea water from the Chesapeake Bay crater" by  Ward E. Sanford, Michael W. Doughten, Tyler B. Coplen, Andrew G. Hunt, and Thomas D. Bullen, Nature 503, 252-256 (14 November 2013), doi: 10.1038/nature12714, [ http://www.nature.com/nature/journal/v503/n7475/full/nature12714.html ], accessed 2013-11-17.

6. "Oldest Large Body of Ancient Seawater Identified under Chesapeake Bay", posted 2013-11-14 at [ http://www.technology.org/2013/11/14/oldest-large-body-ancient-seawater-identified-chesapeake-bay/ ], accessed 2013-11-17.

7. "Seawater discovered near the Chesapeake Bay is up to 150 million years old", by Darryl Fears, published 2013-11-16 at [ http://www.washingtonpost.com/national/health-science/seawater-discovered-near-the-chesapeake-bay-is-up-to-150-million-years-old/2013/11/16/096ac7ae-4e10-11e3-be6b-d3d28122e6d4_story.html ], accessed 2013-11-17.