Bachelor of Science (Honours)
School of Earth & Environmental Science
Rumpca, Nikki, Using sediment geochemistry to reconstruct past variation of weathering in the Himalayan mountain range, Bachelor of Science (Honours), School of Earth & Environmental Science, University of Wollongong, 2012.
The intense rate of physical erosion in the Himalaya Mountains leads to significant changes in the mineralogy and geochemistry of sediments. The nature of these changes has the potential to elucidate the impact of climate, vegetation, additional tributaries, and humans on sediment weathering. Although these changes occur with transportation down river, it is unclear as to the nature of the changes in the mineralogy and geochemistry of sediments is and how these compare to surrounding fluvial terraces. This research focuses on the Alaknanda River, located in the central area of the Himalaya Mountains of India, with 17 fluvial terrace and 8 modern river samples from Nandprayag in the north to Srinagar in the south. Mineralogy, geochemical and petrological analysis of these samples, paired with comparisons between sample sites, distance downstream and terrace age reveal trends mostly related to grain size but significant variation was also discovered With investigation of associations found with XRF analysis and SPSS cluster and principal component analysis, further investigation is required as only weak correlations were discovered. These weak correlations were also discovered with interpretation using XRD and aspects of the sediments with SPSS. Such investigation would aid in providing a more complete understanding of the changes to sediments of the Alaknanda River due to weathering, which not only increases the knowledge and understanding of weathering processes in Himalayan Mountain rivers, but also to other regions of tectonic activity.