Ancient Seawater Discovered in Chesapeake Bay Crater

By: By Laura Dattaro

Published: November 22,2013

 

 

 

 

 

A satellite image of the Chesapeake Bay. (NASA/GSFC Landsat/LDCM EPO Team)

A group of scientists inadvertently stumbled upon a body of water that’s more than 100 million years old.
The scientists, from the United States Geological Survey (USGS), were drilling at Cape Charles, Va., in order to study a crater that was formed when an asteroid or chunk of ice rammed into Earth about 35 million years ago, according to The Washington Post. They unexpectedly discovered “the oldest large body of ancient seawater in the world,” according to the USGS.
When the object hit the Earth, near the mouth of what is now the Chesapeake Bay, it rustled up water already in the sediment, according to National Geographic, trapping it underground in an area about 60-square miles across.
“The ancient seawater was preserved like a prehistoric fly in amber,” the USGS said in a statement.
The water is about twice as salty as modern seawater, the Post reports, which could help explain salty groundwater in the area. Scientists tested the water’s level of chloride, bromide and helium to determine the water’s origins and age.
The water is likely between 100 million and 150 million years old, dating to the Early Cretaceous period, when Stegosaurus and Tyrannosaurus rex were roaming the continents. Studying the water may help scientists understand modern issues like ocean acidification.
“Analyses of ancient seawater are very important in [that] they provide insight into the evolution of life,” marine geologist Peter Swart, who was not involved in the research, told National Geographic.
The findings are published in the journal Nature.