Geological evolution of the Tethys Himalaya

Abstract

Rifting during the late Precambrian created the Tethyan basin in which the sedimentation continued up to Middle Cambrian (Cambrian Series 3). Onset of the late Cambrian-lower Ordovician Kurgiakh orogeny terminated the sedimentation and also deformed the late Precambrian and Cambrian sediments. A shallow marine transgression during the lowermiddle Ordovician resumed the sedimentation with a prominent conglomerate horizon. The conglomerate horizon is absent in the Byans (Kalapani) and Bhutan sectors. The lower Ordovician siliciclastic sediments are succeeded by siliciclastic-algal-coral buildups during the Katian, indicating deepening of the basin; at this juncture the Bhutan and Byans areas too were submerged. There was another subaerial break around the Wenlock, which extended up to the early Devonian. Shallow sea returned in the early-middle Devonian, manifested by the Muth Formation in the western Himalaya. The sea level relatively rose in the Givatian, heralding the siliclastic-carbonate sedimentation that continued upto the Tournaisian. In majority of the areas, there is a hiatus at the end of the Tournaisian. In the distal parts of Spiti-Zanskar sub-basin and Kashmir, however, the sedimentation continued up to Visean/ Serpukhovian. In Spiti-Zanskar, a late Carboniferousearly Permian diamictite horizon is present. The diamictites are assigned glacial origin by many workers. The areas where the sedimentation had ceased during the Tournaisian, witnessed a marine transgression during the Asselian-Sakmarian. It was followedby outpouring of the 289 Ma Panjal Volcanics in parts of Kashmir, Zanskar and Lahaul. The 289 Ma interval represented by abreak between the Sakmarian and the Wuchiapingian sediments in the areas where the Panjal volcanics are absent. The Wuchiapingian transgression was extensive;

Linking the impact of seismicity on palaeogeographic evolution and sedimentary architecture: A case study from Middle Jurassic succession of Spiti Himalaya

“…2a). The SF is composed predominantly of shale, directly transit from FOF and gradationally passes into the Giumal Formation with sand-shale alternation (Bhargava and Singh, 2019). The lithological variation divided the entire sequence into three major divisions: lower, middle and upper members (Fig.…”

“…The Himalayan sedimentary succession deposited along the north-eastern boundary of India in the southern hemisphere of Tethys holds crucial information on Eocambrian to Eocene (Fig. 2a; Bhargava and Singh, 2019; Fursich et al 2021; Albert et al 2021; Sun et al 2021). The Jurassic succession is mainly preserved at the inner part of the higher Himalayas, often representing the scenario during Gondwana’s disintegration.…”

“…The depositional sequence represents a transition from limestone to anoxic black shale (Bhargava and Singh, 2019; Fursich et al 2021; Albert et al 2021). Several studies focus on the change in palaeoclimate and ocean chemistry (Bhargava and Singh, 2019; Fursich et al 2021; Singh et al 2021), while the cause of facies transition is yet to be explored. The present study records a number of beds with soft-sediment deformations on top of the FOF.…”

The Indian Subcontinent: Its Tectonics

“…The THS is typically developed beyond the Great Himalaya on northern passive margin of the Paleoproterozoic-Neoproterozoic Indian Plate during Cambrian to Paleogene/Lower Eocene, and represents a vast sedimentary ~10 km thick pile, deposited in the vast Tethyan Ocean (Bhargava, 2008;Bhargava and Singh, 2020 The Triassic sediments (Lilang Supergroup) are mainly shallow marine carbonate-dominated, followed by rapid deepening, which lasted up to Carnian (Chomule Formation/Hedenstromia Beds). Thereafter, the basin gradually shallowed during Middle Norian for extensive coral reef growths, which terminated due to further basin shallowing.…”

“…Since the THS is also observed within the Lesser Himalayan domain, Myrow et al (2003) and Bhargava and Singh (2020) summarized three models: (i) deposition in two separate tectonic domains, separated by lofty rock barrier, (ii) one single large basin, and (iii) two basins developed at different locations and large scale thrusting along the Main Central Thrust.…”