Chiemgau Crater Strewn Field

The Chiemgau Crater Strewn Field: Evidence of a Holocene Large Impact Event in Southeast Bavaria, Germany
Kord Ernstson, Werner Mayer, Andreas Neumair, Barbara Rappenglück, Michael A. Rappenglück, Dirk Sudhaus and Kurt W. Zeller

Kord Ernstson*a, Werner Mayerb, Andreas Neumairb, Barbara Rappenglückb, Michael A. Rappenglückb, Dirk Sudhausc and Kurt W. Zeller✝d

a University of Würzburg, Am Judengarten 23, 97204 Höchberg, Germany
b Institute for Interdisciplinary Studies, Bahnhofstraße 1, 82205 Gilching, Germany
c Institute of Geography, University of Augsburg, Universitätsstraße 10, 86135 Augsburg, Germany
d Österreichisches Forschungszentrum Dürrnberg, Pflegerplatz 5, 5400 Hallein, Austria

Received 30.01.2009, received in revised form 27.02.2010, accepted 9.03.2010

Abstract. – The Chiemgau strewn field in the Alpine Foreland discovered in the early new millennium comprises more than 80 mostly rimmed craters in a roughly elliptically shaped area with axes of about 60 km and 30 km. The crater diameters range between a few meters and a few hundred meters. Geologically, the craters occur in Pleistocene moraine and fluvio-glacial sediments. The craters and surrounding areas so far investigated in more detail are featuring heavy deformations of the Quaternary cobbles and boulders, abundant fused rock material (impact melt rocks and various glasses), shock-metamorphic effects, and geophysical anomalies. The impact is substantiated by the abundant occurrence of metallic, glass and carbon spherules, accretionary lapilli, and of strange matter in the form of iron silicides like gupeiite and xifengite, and various carbides like, e.g., moissanite SiC. The hitherto established largest crater of the strewn field is Lake Tüttensee exhibiting an 8 m-height rim wall, a rim-to-rim diameter of about 600 m, a depth of roughly 30 m and an extensive ejecta blanket. Physical and archeological dating confine the impact event to have happened most probably between 1300 and 300 B.C. The impactor is suggested to have been a low-density disintegrated, loosely bound asteroid or adisintegrated comet in order to account for the extensive strewn field.

full article http://elib.sfu-kras.ru/bitstream/2311/1631/1/04_.pdf