Suture (geology)

Geosutur, suture zone or only suture (from Latin suture, suture ') is a term used in geology, (eg, continents, island arcs or oceanic plateaus) denotes the interface or zone of contact between formerly separate crustal blocks by plate tectonic processes have collided with each other. Such collisions and thus to the formation of sutures occurs at convergent plate boundaries after the previously located between the crustal blocks oceanic crust was subducted.

A suture is structural geology nothing more than an extended fault zone. Investigations using geophysical methods showed that these fault zones can extend vertically into the upper mantle and laterally over hundreds of kilometers. Geosuturen are characterized by intensely deformed and metamorphic rocks. Ideally occur in the suture zone ophiolitic rocks on Ophiolithkomplexe or suites in a broader sense ( such as the ZEV ), which are the result of a partial shearing of the formerly existing between the crustal blocks collided oceanic crust. Especially in older sutures but this is rarely the case, as the ophiolites were destroyed since formation of the suture either by younger tectonics or erosion.

Prime examples of sutures can be found today within the geologically young alpidischen fold mountains, including the Alps and the Himalayas. Where for about 50 million years conflict with those of the continental crust shares of the African plate and the Indian plate to the Eurasian plate, which once intervening oceanic crust of the Neotethys basin has now been almost entirely subducted. Here some snippets of oceanic crust on the Eurasian plate were autopsied and there are now to be found in the form of typical Geosuturen ophiolites. Because of his relatively advanced age, which today are sometimes missing the mark end ophiolites, the search for sutures in Varistikum is much more difficult.