SAN FRANCISCO, CA About 65 million years ago, an asteroid or comet crashed into a shallow sea near what is now the Yucatn Peninsula of Mexico. The resulting firestorm and global dust cloud caused the extinction of many land plants and large animals, including most of the dinosaurs. At this week's meeting of the American Geophysical Union (AGU) in San Francisco, MBARI researchers will present evidence that remnants from this devastating impact are exposed along the Campeche Escarpmentan immense underwater cliff in the southern Gulf of Mexico.
The ancient meteorite impact created a huge crater, over 160 kilometers across. Unfortunately for geologists, this crater is almost invisible today, buried under hundreds of meters of debris and almost a kilometer of marine sediments. Although fallout from the impact has been found in rocks around the world, surprisingly little research has been done on the rocks close to the impact site, in part because they are so deeply buried. All existing samples of impact deposits close to the crater have come from deep boreholes drilled on the Yucatn Peninsula.
In March 2013, an international team of researchers led by Charlie Paull of the Monterey Bay Aquarium Research Institute (MBARI) created the first detailed map of the Campeche Escarpment. The team used multi-beam sonars on the research vessel Falkor, operated by the Schmidt Ocean Institute. The resulting maps have recently been incorporated in Google Maps and Google Earth for viewing by researchers and the general public.
Paull has long suspected that rocks associated with the impact might be exposed along the Campeche Escarpment, a 600-kilometer-long underwater cliff just northwest of the Yucatn Peninsula. Nearly 4,000 meters tall, the Campeche Escarpment is one of the steepest and tallest underwater features on Earth. It is comparable to one wall of the Grand Canyonexcept that it lies thousands of meters beneath the sea.
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|Contact: Kim Fulton-Bennett|
Monterey Bay Aquarium Research Institute