Shilakong Ophiolite Nappe of Zanskar Mountains, Ladakh Himalaya

Abstract

The Shilakong ophiolite nappe occurs along the crest of the Zanskar Mountains in Ladakh, tectonically resting over the Mesozoic-Cenozoic sediments of the Spiti-Zanskar basin. It comprises two sub-nappe units. The lower Photang sub-nappe is made of pillow lava, basalt, volcanogenic sediments, purple chert and carbonate rocks with slivers of serpentinite. The Spong sub-nappe comprises mainly harzburgite, dunite and lherzolite in different stages of serpentinisation. The Shilakong ophiolite nappe is comparable with the Kiogar-Amlang La ophiolite nappe complex south of Kailas in South Tibet-North Kumaun region. These ophiolite nappes represent squeezed up material from the deep sea regime along the Inclus Tectonic Zone and are now obducted onto the continental zone as the highest allochthon in the Himalaya.