Uplift of Himalayas and its induced Global Environmental Changes

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We carried out geological field investigation and core drilling for academic purpose in the southern part of the Kathmandu Basin, in order to clarify the uplift process of the Himalaya and changes in Indian monsoon during the last 3 myr. Regarding on the drilled cores, we undertook the following studies.1. Paleomagnetic study : we measured natural remanent magnetization and stepwise alternating field demagnetization, and detected two excursions corresponding to Mono Lake and Laschamp excursion.2. 14C age determination : we measured AMS C 14 ages of twelve pieces of carbonized fragment, and clarified that the draining of lake water started at 11 kyr B.P.3. Pollen analysis : we analyzed pollen assemblage of topmost 30 m at 10 cm interval, and obtained a curve of paleoclimatic changes during the last 50 kyr.4. Diatom analysis : we examined the existence and assemblage of fossil diatom, and detected 5 genus 11 species of Centrales and 22 genus and 38 species of Pennales, some of which are useful as indicators of paleoenvironments of the lake.5. Paleobotanical Study : we collected and identified fossil-leaves from more than 160 horizons and examined their significance as indicators of paleoclimate.6. Grain-size distribution : we analyzed grain-size distribution of topmost 30 m, and clarified the difference between lacustrine and fluvial sediments.7. Clay analysis : we carried out clay of topmost 50 m by XRD decomposition method, and obtained a curve of paleoclimatic change during the last 450 kyr.8. Inorganic chemical analysis : we carried out radioactivation analysis of clay of topmost 30 m, and examined the relationship between changes of major and rare-earth elements and climatic changes.9. Organic chemical analysis : we measured amount of total organic carbon and C/N ratio of topmost 30 m at 10 cm interval, and examined the relationship between their changes and environmental and climatic changes.