Work

Late Miocene Uplift and Exhumation of the Lesser Himalaya Recorded by Clumped Isotope Compositions of Detrital Carbonate

Year: 2024

Type: article

Abstract: The Himalaya orogen evolved since the Eocene as the Tethyan‐, Greater‐, Lesser‐ and Sub‐Himalaya thrust sheets were uplifted and exhumed in sequence. Reconstructing the provenance of sediment in Himalayan River systems can inform on stages in the tectonic history of the orogen. Here, we analyze the oxygen, carbon and “clumped” isotope compositions of carbonate minerals from Himalayan bedrock, Ganga River sediments and Bengal Fan turbidite deposits. We demonstrate that river sediments consist of a mixture of Himalayan‐derived and authigenic calcite precipitated in the river system. The relative abundance and clumped isotope apparent temperatures of detrital calcite in turbidite deposits decreased between the Late Miocene and Pliocene, while chemical weathering intensity did not increase during this interval. Considered together, these results reflect the establishment of the Lesser Himalaya as an important carbonate sediment source for Himalayan rivers, driven by the uplift and exhumation of this thrust sheet.

Source: Geophysical Research Letters

DOI: 10.1029/2024gl109643

Authors: U. Ryb, C. Ponton, C. France‐Lanord, K. Yoshida, J. M. Eiler

Institutions: Hebrew University of Jerusalem, Western Washington University, Centre de Recherches Pétrographiques et Géochimiques, Shinshu University, California Institute of Technology

Language: English

Topic: Geological and Geochemical Analysis

Subfield: Geophysics

Field: Earth and Planetary Sciences

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,900

Funders: Agence Nationale de la Recherche, Israel Science Foundation, Japan Society for the Promotion of Science