论文部分内容阅读
We have carried out a study on the variation of strontium isotope composition of river waters, Wujiang and Yuangjiang River, in karst areas of Guizhou Province, China. The results obtained permit us to characterize the geochemistry of the river draining karst terrain and obtain a better understanding of main controls of catchment geology, chemical weathering of different rocks, and evaluate impact of human activities on the environment. The isotopic ratios of dissolved Sr in all rivers are between 87Sr/86Sr =0.7077 and 0.7110, totally lower than the weighted average of 87Sr/86Sr =0.7119 for the world large rivers. The Wujiang River waters have Sr concentrations from 1.0 to 6.1 μmol/L, while the Yuanjiang River waters have much lower Sr concentrations ranging from 0.28 to 1.3 μmol/L. Most of the river waters from the Wujiang river are characterized by low Ca/Sr and Mg/Sr, and 87Sr/86Sr ratios, in which a majority of river waters are of 87Sr/86Sr ratios lower than the average Sr isotope ratio (87Sr/86Sr
We have carried out a study on the variation of strontium isotope composition of river waters, Wujiang and Yuangjiang River, in karst areas of Guizhou Province, China. The results obtained permit us to characterize the geochemistry of the river draining karst terrain and obtain a better understanding of main controls of catchment geology, chemical weathering of different rocks, and evaluate impact of human activities on the environment. The isotopic ratios of dissolved Sr in all rivers are between 87Sr / 86Sr = 0.7077 and 0.7110, totally lower than the weighted average of 87Sr / 86Sr = 0.7119 for the world large rivers. The Wujiang River waters have Sr concentrations from 1.0 to 6.1 μmol / L while the Yuanjiang River waters have much lower lower Sr concentrations ranging from 0.28 to 1.3 μmol / L. Most of the river waters from the Wujiang river are characterized by low Ca / Sr and Mg / Sr, and 87Sr / 86Sr ratios, where a majority of river waters are 87Sr / 86Sr ratios lower than the average Sr isotopop e ratio (87Sr / 86Sr