Utilizing topographic structure for characterizing and understanding process-form relationships of mountain geodynamics in the central Karakoram Himalaya
Abstract
The Karakoram Himalaya exhibits complex mountain geodynamics involving the integration of atmospheric, surface and tectonic processes. Relatively little is known about the role and magnitude of surface processes in relief production, the location and extent of deformation zones, and the nature of polygentic topographic evolution. Complex topography integrates the coupling of numerous systems and processes, although characterizing and mapping the distribution of process regimes, lithology and tectonism is notorious difficult. Consequently, our research objectives were to incorporate topographic structural elements into our geomorphometric analyses to characterize and map the nature of denudation and crustal deformation. Specifically, we utilized a 30 m Shuttle Radar Topographic Mission (SRTM) digital elvation model to extract the ridge and drainage network structure, in order to estimate meso-scale erosion dynamics involving glacial, fluvial and mass wasting processes. We also characterized the drainage network sinuousity and orientation structure related to lithology and geologic structure. We then examined topographic anisotropy to characterize process regimes and crustal deformation zones. Preliminary results indicate that the highest meso-scale relief variations are associated with metasedimentary rocks along the Hunza River, high altitude locations due to glaciation, and along large fault zones including the Karakoram Fault, Kilik Fault, and Karakoram-Kohistan Suture Zone. Drainage network sinuosity and orientation highlight faulting and tectonic zones in and along the Indus River, Hunza region, and Braldu Valley. The topographic anisotropy of numerous geomorphometric properties clearly characterizes faults and crustal deformation zones, as well as differentiates surface process regimes including fluvial incision, glacierization and fluvial sediment fluxes. These results reveal that using topographic structural constraints permit assessment of various components of the mountain geodynamics in the Karakoram and improves geomorphometric terrain characterization and process regime mapping.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFMEP53E1936Y
- Keywords:
-
- 1813 Eco-hydrology;
- HYDROLOGYDE: 1824 Geomorphology: general;
- HYDROLOGYDE: 1825 Geomorphology: fluvial;
- HYDROLOGYDE: 1826 Geomorphology: hillslope;
- HYDROLOGY