Mechanical Models for East-West Extension within the Pamir Orogen: Insights from of the Holocene slip rate of the Kongur Normal Fault

• DOI: 10.5194/egusphere-egu24-7399
• Publication Date: 2024-03-08T16:44:50Z
• Authors: Qi Liu; Jie Chen; Tao Li; Jianhong Xu; Ning Di; Ming Luo

The Pamir orogen, laying at the northwestern syntaxis of Indo-Asian collision zone and one most tectonically active regions central Asia, experiences significant extension in its interior. Although internal is common mature orogens, special because (i) primarily concentrated on Kongur Extensional System (KES) rather than distributed multiple normal faults; (ii) KES localized eastern region centralized, suggesting asymmetric extension; (iii) along decreases southward, instead decreasing from portion to northern southern ends. Because these unique characteristics, causes formation have inspired numerous investigations, which turn led proposal various mechanical models. Defining multi-timescale deformation rates KES, especially for late Quaternary modern slip rate, prerequisite better understanding nature Pamir.In this study, we focus debated structure within Pamir: nearly NNW-trending Normal Fault (KNF), primary striking part KES. This fault characterized by dramatically increased topography (elevation up > 7,500 m) expressed as lofty Muztaghata massif footwall. Thermochronology ages suggest that initiation, largest magnitude highest long-term exhumation are vicinity massif. some studies focused determining tectonic activity since Cenozoic, almost no estimate yet exists (KNF) bounding Moreover, Glaciers oscillated considerably throughout massif, offering a opportunity expand our role glaciers shaping topography.At Bulunkou, KNF branched into two segment. surface trace both segments clearly visible straight line feature, offsets different geomorphic surfaces. We determined Holocene segment through mapping high-resolution DEMs cosmogenic 10Be exposure dating boulders displaced Finally, observed very high (even probably can reach 10-13 mm/a) Bulunkou. Correlating new observations with kinematics whole clarify accommodating Pamir.