Himalayan Geology, Vol. 42 (1), 2021, pp. 85-92, Printed in India
Geological mapping and structural analysis in Shantipur-WamiTaksar area of Gulmi-Baglung district, western Nepal to assess the Badi Gad Fault and related features
PASHUPATI GAIRE*, KABI RAJ PAUDYAL
Central Department of Geology, Tribhuwan University, Kathmandu, Nepal
*Email (Corresponding Author): pashupatigaire11@gmail.com
Abstract: A geological study was carried out in the west-central Nepal Lesser Himalaya between Shantipur-WamiTaksar area of Gulmi and Baglung districts. The main aim of the study was to prepare a geological map and cross-sections at 1:25,000 scales to assess the geology and the geological structures of the region. Two geological units namely the Nourpul Formation and the Dhading Dolomite were mapped. The Nourpul Formation consists of succession of phyllite and meta-sandstone with sub-ordinates of quartzite and dolomite. The Dhading Dolomite consists of monotonous succession of grey, siliceous dolomite with columnar stromatolites. The contact between these two units is sharp. The area is highly folded with several local and regional anticlines and synclines. They are named as the Juniya-Limgha Syncline, Jyam Danda Anticline, Saylan Syncline and Sukhaura Anticline respectively towards NE. Almost all the folds trend WNW. The origin of these folds can be linked with the thrust propagation in the Himalaya that can be explained with the deformation event D4. All the folds in the study area are open folds. Brittle-type shear zones are mapped in field continuously along the Badi Gad Khola section. Presence of fault is clearly evidenced by well-developed fault gouge, breccias, spring lines and clustering of large landslides which represents the continuous linear zone indicating the presence of the Badi Gad Fault, a strike-slip fault of the Lesser Himalaya. Only one major thrust the Harewa Khola Thrust is mapped, which has brought the older Nourpul Formation over the younger rocks of the Dhading Dolomite. The Harewa Khola Thrust is probably a back-fault, as indicated by southward dipping of rocks as well as thrust.
Keywords: Lesser Himalaya, Badi Gad Fault, Harewa Khola Thrust, deformation event, western Nepal
