Wilkesland crater
The Wilkesland meteorite is a hypothetical meteorite that scientists hold responsible for causing a huge impact crater under the Antarctic ice. The consequences of its impact are also increasingly attributed to the mass extinction on the Permian-Triassic border . The scientific discussion is ongoing ( see also: Bedout structure and Siberian Trapp ).
Discovery of the impact crater
In May / June 2006, evaluations of the GRACE satellite data under the Antarctic ice in Wilkesland discovered a mascon ( gravity anomaly ) similar to the one known on the moon. Airborne radar images showed a crater almost 500 km in diameter at the site. The crater was probably formed around 250 million years ago by the impact of a large meteorite. The meteorite could have had a diameter of up to 50 km and was thus possibly approximately 120 times the volume of the Chicxulub meteorite , which is held responsible for the extinction of the dinosaurs 66 million years ago.
According to the scientists, the force of the impact in Wilkesland was catastrophic for the earth at that time and its inhabitants. Hypothetically, it is partly responsible for the largest mass extinction in Earth's history at the end of the Permian, when around 70 percent of all land life and over 90 percent of marine species became extinct. In addition, the impact probably contributed to the formation of a rift in the eastern Indian Ocean and thus ultimately led to the separation of Australia from the great continent of Gondwana . From the species that survived the upheavals, the dinosaurs developed into the living beings dominating the fauna for the following three geological ages, the Triassic , Jurassic and Cretaceous .
Web links
- Report on the discovery of the crater (English)
- Trail of Destruction (Wissenschaft.de)
Coordinates: 70 ° 0 ′ 0 ″ S , 120 ° 0 ′ 0 ″ E