Ms. Terri Bannister, one of the graduate students in the School of Geosciences, travelled to Nepal this past summer with two Geoscience Faculty members, Drs. Tim Duex and Durga Poudel, for her thesis research in Nepal. Ms. Bannister is studying geo-hazards and land degradation using GIS and Remote Sensing in the Chure region of Nepal. Nepal consists of primarily five physiographic units which run parallel from east to west. From south to north they include, the Indo-Gangetic Plain, the Chure Range or Siwalik Range, the Lesser Himalaya, the Higher/Tethyan Himalaya, and the Tibetan Plateau. These physiographic units are separated by east-west running thrust fault systems. The Chure Region rises steeply from the flat lands of Indo-Gangetic plains and these hills are geologically young (12 million years and older), and are frequently comprised of rocks/minerals that are structurally weak and have a high potential for erosion hazards. The Siwalik Range consists of Miocene to Pliocene age upward-coarsening successions of fluvial mudstone, siltstone, sandstone, and conglomerate known as the Siwaliks Group that have been highly tilted by the Himalayan Orogeny. The relatively young age, steep inclination, and fine-grained makeup of the rocks contribute to their ease of erosion.
The Chure region has experienced recent rapid fluvial erosion, high sediment loads in braided streams, destruction of agricultural lands, deforestation, and loss of properties and life. The thesis study aims at understanding the extent and magnitude of land use changes over time, land degradation, slope failures and landslides, debris deposition, gravels and mining and identification of the river bank areas that are geomorphologically stable for agricultural or other uses. Extensive field work and detailed geohazard surveys were conducted in the Bara and Rautahat districts of the Chure region. This visit also allowed her to do ground-truthing of vegetation indices and land use types that she had developed and had detected through satellite images and other available data. In addition, gravel shipping and mining data, topo maps, and other necessary data sets were collected for the thesis study. The team was also able to visit government officials and share their preliminary findings in relation to Chure degradation and Ms. Bannister’s thesis work in Nepal. The government officials were very supportive and were keen about Ms. Bannister’s thesis results. Terri will defend her thesis in the Fall of 2015.