Sunday, May 16, 2010

Accretionary Wedge #25: Geo-Image

The current edition of the "Accretionary Wedge" is hosted by Highly Allochthonous. The motif this month is to gather geology-related images. Outcrops, sections, satellite images, minerals, fossils, seismic images, diagramms etc.

Here is mine: The Permian-Triassic transition epxosed at the Northface of the "Aferer Geisler" (Dolomites, Northern Italy).

The Bellerophon Formation (the brown/yellow succession in the lower part) represents late Permian (Changhsingian) shallow marine to marginal marine environments that yield insight into the pre-extinction world. The end-Permian mass extinction is suggested to have wiped out about 95% of all marine species, and thus is considered as the most severe biotic crisis that metazoan life encountered on our planet. The Werfen Formation (the grey to reddish slope in the middle part of the picture) extends from the latest Permian (latest Changhsingian) to the lower Triassic (Induan/Olenkian) and is one of the best studied succession of the end-Permian mass extinction and its aftermath. In this picture, the extinction level is exposed approximately where the trees end. The steep cliffs forming the top of this range are composed of reef carbonates for which the Dolomites are so noted.

The Dolomite region has been selected as a Unesco World Heritage site. Besides the breath-taking beauty of this landscape, the significance of this region for earth sciences has also been taken into account.

1 comment:

Anne Jefferson said...

Neat photo. I can't wait to visit the Dolomites some day.