Bletterbach
The Bletterbach is a creek in the South Tyrolean Aldein. It forms at the foot of the White Horn Bletterbachschlucht, which is also referred to as the " Grand Canyon of South Tyrol". The gorge was created about 15,000 years ago during the Ice Age. It is about 8 km long and 400 m deep. Researchers made here already some great fossils and therefore the Bletterbach is so well known. The many different rock groups of the Dolomites can be found here.
The creek formed by the erosion not only the canyon, but also some rock formations that resemble faces and give popular photo opportunities.
Geological profile
The lowest rock strata that are open in the Bletterbach belong to the Etschtaler volcanic group, which is also called Bozen quartz porphyry. It is here before about 280 million years ago, resulting volcanics.
Store on the rocks of the Etschtaler Vulkanitgruppe with 250 meters thickness of the sedimentary rocks also still Permian Val Gardena lineup. What is striking is mainly reddish color of the sandstones. In the lower part there usually are river sediments in which different sedimentary structures such as ripple marks, cross stratification, cross-bedding or dry cracks can be seen. At the top of the rocks have an increasingly marine influence. Here is known to fossil -rich, calcareous cephalopod at the top of the butter hole waterfall. The Val Gardena formation penetrated by some Vulkanitgängen and in the area of butter hole there is a striking Schlotbrekzie. The volcanics have trias sian age, their formation is dated in the Ladinian or Carnian.
In the valley here is about 60 m thick Upper Permian Bellerophon Formation is open to the Val Gardena Formation. The evaporitic rocks are affected, partly bituminous. Also in the Bellerophon Formation can be seen towards the top a transgressive trend, that is, that the bottom even more terrigenous sediments influenced upwards increasingly in the sea resulting developments are.
With a few meters thick Oolithbank sets on the Bellerophon Formation throwing a the lineup that has arisen in the lower Triassic. The highly differentiated itself in formation goes back in part to formation of a Wadden Sea. About the Werfen Formation follows the Richthofen Conglomerate and above that of the sarl dolomite. Both are in the middle Triassic, dated to the Anisian. The sarl dolomite also builds the summit of the White Horn.