Hydrochemic Characteristics and Tectonic Situation of Selected Springs in Central and NW Yunnan Province, China

Povzetek

The Yunnan Province lies on the eastern rim of the collision zone between the Indian plate and Eurasia. This region is characterized by complex Cenozoic structures and active seismotectonics. In the year 2004 the areas north from Kunming and the NW part of Yunnan were studied. The measurements of the temperature, conductivity and the analyses of carbonate, phosphate and nitrate were performed in Quinglongtan spring and in the accumulation lake that is situated lower than the spring. The springs are situated in the wider zone of the Xiaojiang fault along which left horizontal movements are taking place. Along the wider zone of the Zhongdian fault between the town of Zhongdian and the Yangtze River on the south there are more springs. Tiansheng Qiao (T = 57.5ºC) and Xiageiwenquan (T = 48,3 − 66.8ºC) are thermal springs along which tufa is deposited. The Baishuitai spring has high mineralization and lower temperature (T = 11.1 − 13.3ºC) and deposits calcium carbonate in the form of gours. All studied springs are connected with active fault zones. The studied areas mostly represent the contact areas between carbonate and non-carbonate rocks.