新西兰陶波火山区水化学特征及其成因初探

Preliminary Study on Hydrochemistry and Genesis of Water from the Taupo Volcanic Zone,New Zealand

陶波火山区以流纹质岩浆活动为特征,发育闻名于世的地热田。通过采集新西兰陶波火山区的火山喷泉热水、地表水等不同类型的水样进行水化学和同位素分析,探讨罗托鲁阿怀欧塔普地热公园内的地热水起源、汤加里罗火山公园内的苏打泉瀑布补给来源。研究结果表明怀欧塔普地热公园出露的地热水存在原生高砷的污染问题,其来源为变质水。苏打泉瀑布水样的氢氧同位素指标在新西兰大气降水线分布范围内,说明该瀑布水与大气降水密切相关。本研究为新西兰陶波火山区地热水和地表水后续深入研究提供参考依据。

The Taupo Volcanic Zone （TVZ） in New Zealand is famous for its rhyolitic volcanism which formed world-class geothermal fields. We conducted chemical and isotopic analysis on various types of water samples collected from the TVZ of New Zealand, including geothermal water and surface water in order to determine the genesis of geothermal water in Wai - 0 - Tapu geothermal wonderland （Rotorura） and the source of the Soda Spring Waterfall （ Tangariro Geological Park）. Analytical results show that the geothermal water in Wai - 0 - Tapu geothermal wonderland has been polluted by the native arsenium which was derived from metamorphic water. The isotopic composition data of water samples from the Soda Spring Waterfall occur along the distribution line of the atmospheric precipitation of New Zealand, indicating that the water supply of the Soda Spring Waterfall was closely related to atmospheric water. This research provides a preliminary dataset for further studies on the geothermal water and surface water in the TVZ of New Zealand.