Internal Structure of Four Rock Glaciers in the Northern Tien Shan from Geophysical Investigations

Ella Wood, Tobias Bolch, Lothar Schrott, Francesca Baldacchino, Vassiliy Kapitsa, Foteh Rahimov, Alibek Taskynbayev

2025

Full text Open access: Gold Metadata (CSL-JSON)
DOI 10.5194/egusphere-egu25-8741
Data confidence 70 medium
How this score is calculated

It is built from checkable properties of the record itself: whether the article has a DOI, how many independent sources confirmed its data, whether the required fields are filled in, and how recent the latest confirmation is. Disagreement between sources and a missing identifier lower it. A value of 80 or above means the record was published without further checking; 60 to 79 means it is published at reduced confidence, with a manual check advisable. A record verified by an editor by hand is never pushed below 90 by a recalculation. This scores our data about the article, not the article itself.

Abstract

The cryosphere in Central Asia is critically important as a source of water. Widespread glacier mass loss has been observed across the Tien Shan in response to rising temperatures, raising concerns over future water resources. The Northern Tien Shan, situated along the border of Kazakhstan and Kyrgyzstan hosts almost 700 rock glaciers, including a number of notably large, fast flowing landforms, connected to clean ice glaciers. Despite their prevalence, little is known about the volume and distribution of ice within these rock glaciers. Previous studies have highlighted the potential hydrological significance of rock glaciers both globally and in the Tien Shan, but field data to support this assumption remains limited, particularly outside of Europe.Here, we present the results of geophysical investigations on four glacier or glacier-forefield connected rock glaciers in the Ulken Almaty Valley, Kazakhstan, conducted in July 2024. The investigations aim to provide key information on the internal structure of these rock glaciers, focusing on the internal architecture and spatial distribution of ice. We conducted Electrical Resistivity Tomography (ERT) and Ground Penetrating Radar (GPR) surveys using a 48-electrode ERT device and a 100MHz GPR. ERT surveys were conducted on the two larger rock glaciers (Morennyi and Gorodetsky), whilst GPR surveys were conducted across all four rock glaciers. In total, 10 ERT profiles with a combined length over 3 km and approximately 10 km of GPR profiles were collected. Initial results reveal areas of high ice content with a heterogenous distribution related to morphological features. This research builds on previous remote sensing work examining rock glacier surface kinematics, aiming to better understand the relationships between surface flow processes and rock glacier internal structure.