Climatic and tectonic significance of Taboche Lake, Khumbu Region, Nepal

Ananta P Gajurel; Mary S Hubbard; Bibek Giri; Aurora C Elmore; Sanjeet Maka; Patrick A Rafter; Aaron E Putnam; Sandra Elvin; Alex Tait; Paul A Mayewski

doi:10.1016/j.isci.2021.102418

Climatic and tectonic significance of Taboche Lake, Khumbu Region, Nepal

iScience. 2021 Apr 28;24(5):102418. doi: 10.1016/j.isci.2021.102418. eCollection 2021 May 21.

Authors

Affiliations

¹ Department of Geology, Tribhuvan University, Kathmandu, Nepal.
² Department of Earth Sciences, Montana State University, Bozeman, MT, USA.
³ National Geographic Society, Washington, DC, USA.
⁴ University of California, Irvine, CA, USA.
⁵ Climate Change Institute, University of Maine, Orono, ME, USA.
⁶ School of Earth and Climate Sciences, University of Maine, Orono, ME, USA.

Abstract

The Everest region is characterized by its alpine glacial environment. In an effort to understand environmental change and tectonic activity, our team cored Taboche Lake, situated at 4,712 m along the western margin of the Ngozumpa Glacier. This research catalogs past earthquakes using geological records of the lake core that are important for the assessment of future earthquake hazards in the region and provides information for tectonic risk of glacial lake floods. Core grain size characteristics and internal sedimentary structures from computed tomographic scan were coupled with radiocarbon dating of organic matter preserved in the core to reconstruct the environmental history of the area. The 58-cm-long core consists of laminated silty sands and sandy silts with particle diameters <2 mm. The core records a syn-sedimentary deformational structure, folded sediments, rhythmically alternating dark- and light-colored laminations, and turbidites, which indicate coeval climatic and tectonic variations over the past ∼1,600 years.

Keywords: Glacial Landscapes; Glacial Processes; Sedimentology; Tectonics.