Landforms ( The himalayas) - Assignment Example

Mountain fronts of Himalayas as corollary related to orogen-scale structures. The conspicuous three primary structures of Himalayas ranging from north-south include main boundary thrust (MBT), main central thrust (MCT), and Himalayan frontal thrust (HFT). The major topographic breaks of Himalayas remain in association with the three thrusts. Himalaya’s structure has six primary lithotectonic zones, which occur in parallel belts. The regions include trans-Himalayan batholiths, Tibetan Himalaya, Indus-Tsangpo Suture zone, Lesser Himalaya, Lesser Himalaya, Sub-Himalaya, and Greater Himalaya.

The tectonic environments within Himalaya zones also vary. Immense collision of tectonic plates resulted into the formation of island-arc margin in Western Himalayas and Andean-type margin within the central eastern part of Himalayas. Trans-Himalayan zone has a linear plutonic complex structure. Trans Himalaya zone have its surface partly covered by continental molasse sedimentary rocks and forearc rocks. Trans Himalaya assembly of rocks originates from magmatic rocks uplift and their subsequent erosion.

Igneous complex of the area consists of granites, gabbros, and diorites. The magmatic rocks originate from partial melting of subducting NeoTethyan slab underneath Asian plate. However, the igneous rocks, on the contrary, represents Andean-type environment. ITZS defines the region of collision between Kohistan-Ladakh arc and Indian plate in Tibetan Lhasa block in the east and Western Himalayas. ITZS also demarcates the area along which subduction process consumed Tethys Ocean. ITZS covers more than 2000 km in length with complete successions of rocks that may consist of diamonds that explain the higher pressures during subduction and rapid extrusion along suture zones.

There are also traces of glaucophane schists along the narrow belts along ITSZ in Pakistan. Tethys Ocean also consists of red sandstones and