Geological evolution of the Tethys Himalaya

Abstract

The Tethys Himalaya (TH), also known as "Tibetan Zone", is one of the major tectonic domains within the Himalayan orogen, stretching for approximately 2,000 km from Kashmir and the Zanskar-Spiti synclinorium to South Tibet. After a general description of the stratigraphy of the TH, this chapter focuses on two different sections, located in Ladakh and Dolpo (Western Nepal) where the sequence is spectacularly exposed. The base of the drift sequence is represented either by a major disconformity with an erosion surface reaching down to the Devonian, Silurian or even Ordovician or, in thicker sections, by a paraconformity mantled by condensed horizons of hybrid and ferruginous arenites dated biostratigraphically as mid-Sakmarian. The Paleocene begins with the deposition of coastal quartzarenites capped by condensed glauconitic layers and overlain by thick shallow-marine carbonates with rich benthic foraminiferal faunas spanning the Selandian and Thanetian.