Impact origin for the Hummeln structure (Sweden) and its link to the Ordovician disruption of the L chondrite parent body

Research output: Contribution to journalArticle

Abstract

Several studies of meteorites show that a large disruption of an asteroid occurred ca. 470 Ma in our solar system's asteroid belt. As a consequence, a large number of meteorite impacts occurred on Earth during the following few million years. The finding and characterization, for the first time, of planar deformation features in quartz grains from rocks collected at the Middle Ordovician Hummeln structure (Sweden) prove the hypervelocity impact origin of the structure. The unambiguous shock features allow us to close an similar to 200-yr-old discussion about its origin, and further the hypothesis of enhanced asteroid bombardment during the Middle Ordovician, adding an impact crater to the increasing number confirmed and properly dated from this period. Despite its relatively small size (similar to 1.2 km in diameter), similar to the young Meteor Crater (Arizona, USA), and its old age, the Hummeln structure is remarkably well preserved, contradicting the general assumption that small craters are not preserved on Earth for more than a few tens of thousands to a couple of million years.

Details

Authors
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Geology
Original languageEnglish
Pages (from-to)279-282
JournalGeology
Volume43
Issue number4
Publication statusPublished - 2015
Publication categoryResearch
Peer-reviewedYes

Related research output

Sanna Alwmark, 2016, Lund: Lund University, Faculty of Science, Department of Geology, Lithosphere and Biosphere Science. 138 p.

Research output: ThesisDoctoral Thesis (compilation)

View all (1)