Fluvial Geochemistry of the Arctic Rivers of Eastern Siberia

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9814903EdmondThis proposal requests support to continue long-term investigations of the fluvial geochemistry of the large pristine rivers in the Russian Far East, east of Lake Baikal. The objective is a comparative study, using existing results from the Tropics and this survey, on the influence of climate on weathering rates, specifically the C02 consumption rates by aluminosilicate degradation, OC02 in moles/kM2/yr. None is found! Since all models of paleo-climate on geological time-scales assume a very strong relationship, -x IO over the -30'C range examined (only summer temperatures included), the results are dramatic and unexpected and therefore controversial. It is proposed to continue this work in the Amur, a relatively uncontaminated Temperate river, on remote streams in the Far East that drain its extremes, including the Kamchatka Peninsula and the high Arctic, and on the headwaters of the Olekma and Vitim (major right-bank tributaries of the Lena) that have sources in the Trans-Baikal Highlands east and south of Lake Baikal and may provide the closest analogues to the basement terrains already sampled at Tropical latitudes in the Amazon, Orinoco and Congo and to eroded Iiimalayan-type collision zones. The parallel program on minor and trace element geochemistry will continue. The studies of the geochemistry and petrology of the river sands will be carried on by collaborators at no cost to this proposal; water, suspended and bed load samples will be distributed to qualified investigators in the US and overseas in the usual manner