Origin and reservoir characters of non-volcanic geothermal resources of northern Thailand (Phase 2)

形成非火山泰国地热沃茨的热源、水循环系统和热交换机制是有待解决的问题。以下是我们的研究结果。(1)在花岗岩区以外的地区也有高氦同位素异常。(2)伽马能谱法是地热勘查的有效方法。(3)第四纪玄武岩的岩浆房小而深，但有些岩浆房年轻，足以提供热量。(4)花岗岩的产热范围为8-18 HGU。它对应于在3- 5 km深度处获得300 ℃。(5)外围温泉区蚀变年龄较老。表明火山地热系统的热液活动长期持续。(6)岩心包裹体均匀化温度与实测值基本一致。(7)浅层储层的计算机模拟显示了直到8610年之后的流动模式的变化。

The heat source, water circulation system and heat exchange mechanism to form non-volcanic Thai geothermal waters are problems to be solved. Following are results of our study.(1) High heliun isotope anomalies are found outside of granitic area. (2) Gamma ray spectrometry is good for geothermal exploration. (3) Magma chamber of the Quaternary basalt is small and deep but some of them are youg enough to supply heat. (4) Heat generation from granitic rocks are range from 8-18 HGU. It corresponds to get 300ﾟC at the depth of 3-5km. (5) Alteration ages of outside hot spring areas are relatively old. It indicates that the hydrothermal activity of volcanic geothermal systems had been continued long time. (6) Fluid inclusion homogenized temperatures of drilling core are almost same as measured ones. (7) Computmodeling of shallow reservoir shows the change of flow patterns until after 8610 years.