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1 correction found
the asteroid that formed the Chesapeake Bay
The Chesapeake Bay was not formed by an asteroid impact. Geologists say the modern bay formed much later when rising seas drowned the Susquehanna River valley, while the impact crater only influenced the bay’s later location and shape.
Full reasoning
This claim compresses two different geologic events into one and gets the bay's origin wrong.
- The asteroid/bolide impact happened about 35 million years ago and created the Chesapeake Bay impact crater beneath the lower bay.
- But the modern Chesapeake Bay itself formed far later, after the last Ice Age, when sea level rise flooded the ancestral Susquehanna River valley.
Authoritative sources say this directly:
- USGS: "The Chesapeake Bay is the drowned, ancestral valley of the Susquehanna River." It explains that by about 10,000 years ago the ancient river valley was flooded and became an estuary.
- Chesapeake Bay Program: "This impact did not create the Bay, but it did contribute to natural processes that eventually formed the Bay as we see it today."
- National Park Service: the impact crater "helped determine the location of the Chesapeake Bay," but the bay formed when melting glaciers and sea-level rise filled the river valley.
So the asteroid did not form the Chesapeake Bay itself; it formed a buried crater that later affected where part of the bay developed.
3 sources
- USGS Fact Sheet 102-98 - The Chesapeake Bay: Geologic Product of Rising Sea Level
The Chesapeake Bay is the drowned, ancestral valley of the Susquehanna River... by 10,000 years ago, the main channel of the ancient Susquehanna River valley was flooded and became a narrow estuary.
- Chesapeake Bay Program: How was the Chesapeake Bay formed?
This impact did not create the Bay, but it did contribute to natural processes that eventually formed the Bay as we see it today.
- National Park Service - Climatic and Geological History of the Chesapeake
This impact created a wide crater that is now hidden under the waters of the lower Chesapeake Bay. This large depression helped determine the location of the Chesapeake Bay... the river's valley gradually filled with water and became a wide Bay.