Tso Morari Research Articles

Development of major structures across the northwestern Himalaya, India

The Himalaya originated as a result of subduction of the Tethyan oceanic crust that lay between India and Tibet followed by continent-continent collision. A petrotectonic assemblage of the subduction complex consisting of the Shergol ophiolitic melange, the Nidar ophiolite, the Nindam flysch Formation and blue-schist rocks were obducted over the Indian margin during initial collision of the Indian continent with Tibet in the middle Eocene. The collision was followed by continued convergence of India against Tibet resulting in crustal shortening both in the Indian and the Tibetan margins. This crustal shortening produced regional metamorphism and polyphase deformation of the Higher Himalaya zone, the Tso Morari Crystallines and the Pangong Tso group. Continued convergence produced major folds, nappes and thrusts of the Higher, Tethys and Lesser Himalayas on the Indian plate and the Indus, Shyok and Karakoram zones of the Trans-Himalaya. The major structures include the Main Karakoram Thrust, Zanskar Thrust, Tso Morari dome, Zanskar synform, Sum dome, Kashmir-Chamba nappe, Panjal Thrust and MBT. The compressional phase was followed by an uplift phase in the early Miocene which formed a foredeep to the south in front of the uplifted cordillera. The Siwalik group sediments were deposited in this foredeep and were later folded and faulted. The folds and thrusts in the Outer Himalaya belt are younger than those of other tectonic zones of the Himalaya.

An overview of thrusts and nappes of western Himalaya

Summary The Shali-Deoban Parautochthon, Krol Berinag Nappes and Outer Crystallines Nappes are the main lithostructural units of the Lesser Himalaya of Kumaun, Garhwal and eastern Himachal. Two thrust sheets, the Chail Nappe and the Jutogh Nappe are recognized in the Outer Crystallines Nappes. The Chail Nappe forms a separate thrust sheet, and the Jutogh Nappe overlying it represents a southward extension of the Central Crystallines Nappe of the Higher Himalaya. The Chail Nappe rocks constitute the base of the Palaeozoic-Mesozoic sequence of the Kashmir-Chamba Parautochthon, whereas the Central Crystallines Nappe forms the basement for the late Precambrian-Cretaceous sequence of the Tethyan Zone in the Kumaun, Spiti and Zaskar regions. The Central Crystallines Nappe shows a progressive regional metamorphism, chlorite to sillimanite grade, whereas the metamorphism of the Chail Nappe is mainly confined to the greenschist facies. Metamorphic inversion is a characteristic feature of the Jutogh Nappe which occurs as crystalline klippen in the Lesser Himalaya Zone. The ophiolite suite of rocks of the Indus-Tsangpo suture occurs also as klippen above the sediments of the Tethys Himalaya and metamorphics of the Tso Morari Dome. They appear to have resulted from squeezing out from the root zone and subsequent gravity gliding. The Indus Suture Zone is unique with regard to its thrust tectonics, in that, whereas all the principal thrusts elsewhere in the Himalaya are directed towards the S, within this zone they are directed only toward the N.

The Tso Morari Nappe of the Ladakh Himalaya: formation and exhumation

DOI = 10.3126/hjs.v5i7.1254 Himalayan Journal of Sciences Vol.5(7) (Special Issue) 2008 p.52

The metamorphism of the Tso Morari ultra-high pressure nappe of the Ladakh Himalaya

DOI = 10.3126/hjs.v5i7.1336 Himalayan Journal of Sciences Vol.5(7) (Special Issue) 2008 p.157-8

New occurrence of eclogitic continental rocks in NW Himalaya: The Stak massif in northern Pakistan

DOI = 10.3126/hjs.v5i7.1259 Himalayan Journal of Sciences Vol.5(7) (Special Issue) 2008 p.57

The Tectonics of the Tso Morari Ultra High Pressure Nappe in Ladakh, NW Indian Himalaya

DOI = 10.3126/hjs.v5i7.1337 Himalayan Journal of Sciences Vol.5(7) (Special Issue) 2008 p.159-160

Discovery of granulitized eclogite in North Sikkim expands the Eastern Himalaya high-pressure province

DOI = 10.3126/hjs.v5i7.1312 Himalayan Journal of Sciences Vol.5(7) (Special Issue) 2008 p.126-127

Petrology and geochronology of eclogitic and retrograde micas from Tso Morari UHP Complex, Ladakh Himalaya

DOI = 10.3126/hjs.v5i7.1342 Himalayan Journal of Sciences Vol.5(7) (Special Issue) 2008 p.167

Amphibole compositions as indicators of deep crustal and mantle processes in subduction zones: case study – Tso Morari metamafics, Ladakh, Himalaya

DOI = 10.3126/hjs.v5i7.1325 Himalayan Journal of Sciences Vol.5(7) (Special Issue) 2008 p.144

Crustal velocity structure from surface wave dispersion tomography in the Indian Himalaya

DOI = 10.3126/hjs.v5i7.1240 Himalayan Journal of Sciences Vol.5(7) (Special Issue) 2008 p.33