Gold miners discover 100 million-year-old meteorite crater Down Under
Gold miners in the Australian Outback recently discovered a gigantic meteorite crater dating to about 100 million years ago, back when dinosaurs roamed the Earth.
Found near the Western Australian town of Ora Banda, the newly dubbed Ora Banda Impact Crater is about 3 miles (5 kilometers) across. This huge hole was likely created by a meteorite up to 660 feet (200 meters) wide, or longer than the length of two American football fields, according to Resourc.ly, a Western Australia news outlet.
When geologists at Evolution Mining, an Australian gold mining company, came across some unusual rock cores at Ora Banda, they called Jayson Meyers, the principal geophysicist, director and founder of Resource Potentials, a geophysics consulting and contracting company in Perth. Meyers examined the geologists' drill core samples, as well as rock samples from the site, and he immediately noticed the shatter cones — telltale signs of a meteorite crash. ...
Because "we know they didn't do any nuclear testing at Ora Banda," the evidence suggests that an ancient impact crater hit the site, Meyers told Resourc.ly. ...
To learn more, Meyers examined the site's topography (that is, its varying elevations) and examined a gravity anomaly map, which shows how the gravity field at a particular site differs from a uniform, featureless Earth, according to NASA's Earth Observatory, which wasn't involved in the finding. ...
Meyer's work revealed a hidden impact crater with a pucker in the middle. This pucker is where shattered rocks came back to the surface after the comet struck, like a compressed spring that bounces back, Resourc.ly reported. When the geologists went to the "pucker" part of the site, they discovered shatter cones in the rocky outcrops. ...
Research on zircons and other minerals from the crater will likely reveal when the meteorite struck — right now, Meyers thinks it hit between 250 million and 40 million years ago. ...