In late fall the Alpenglow spellbinds the steep flanks of 13280 ft (4048 m) high Piz Bernina with its glaciated ridge Biancograt. The rising shades almost reached the jagged peaks of Piz Roseg (12916 ft, 3937 m) and its 12854 ft (3918 m) high Schneekuppe. This snow accumulation region nourishes the Tschierva glacier of 2.8 mi (4.5 km) length and 0.6 mi (1 km) width. The huge lateral moraines from the last glacial maximum of 1850 indicate the vast volume of the glacier at that time. At an elevation of 7086 ft (2160 m) the creek Ova da Roseg originates at the mouth of the glacier that drains its water into the river Inn. The Bernina mountain range in the southeast of the Swiss Alps is geologically connected to the Lower East-Alpine nappe. This area contains the remains of the micro-continent East-Alpine that sheared forward off the Adriatic continent plate (Italy and Adriatic) bordering the Penninic Ocean to the North. Accordingly the rocks in this area originate from both continental-granitoide and submarine-volcanic types. Piz Bernina consists of Diorite and Gabbro, which are typical rocks of the deep continental crystalline bedrock. These rocks are about 300 million years old and were formed during the Variscan orogeny. Below these formations about 125 million years old turbidites are located. They originated from underwater rock avalanches that slided down the continental margin into the deep sea. Additionally, deep ocean sediments occur along with former volcanic ocean floor material of the Penninic Ocean that metamorphosed into picturesque green stones called serpentinite. A specimen of this rock type can be seen in the right foreground.
Canon 5D MkII, Canon L 16-35 mm, f/16, 2 sec, ISO 100, polarization filter
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