Influences of Hydraulic Fracturing on Fluid Flow and Mineralization at the Vein-Type Tungsten Deposits in Southern China
Influences of Hydraulic Fracturing on Fluid Flow and Mineralization at the Vein-Type Tungsten Deposits in Southern China
复制标题
水力压裂对华南脉状钨矿床流体流动和成矿的影响
DOI：
10.1155/2017/4673421
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发表时间：
2017-07
期刊：
影响因子：
1.7
通讯作者：
Zhang Dehui
中科院分区：
文献类型：
--
作者：
Liu Xiangchong;Xing Huilin;Zhang Dehui
黑钨矿是南岭脉状钨矿床的主要矿石矿物，是世界一流的钨矿大省。黑钨矿是如何在这些矿床中沉淀的尚无定论，也没有人研究过流体流动与成矿作用的机械过程的联系。采用有限元数值实验研究了水力压裂过程对流体流动及CO2和石英溶解度的影响。在数值实验中，流体为NaCl水溶液，流体压力是控制CO2和石英溶解度的唯一变量。岩石被高压流体破坏后，流体压力和高速热液脉冲出现显著波动。水力压裂引起的流体压降可使石英溶解度降低9%。这种数量的石英沉积可能不会导致岩石渗透性的显著降低。水力压裂后流体压力的降低也会使CO2的溶解度降低36%，并使pH值升高。由于pH值的升高会导致钨的溶解度大幅降低，因此水力压裂过程中流体压力的降低有利于黑钨矿的沉淀。我们的数值实验揭示了南岭钨矿床中黑钨矿的沉淀机制，以及其他溶解度与pH值密切相关的金属。
Wolframite is the main ore mineral at the vein-type tungsten deposits in the Nanling Range, which is a world-class tungsten province. It is disputed how wolframite is precipitated at these deposits and no one has yet studied the links of the mechanical processes to fluid flow and mineralization. Finite element-based numerical experiments are used to investigate the influences of a hydraulic fracturing process on fluid flow and solubility of CO2 and quartz. The fluids are aqueous NaCl solutions and fluid pressure is the only variable controlling solubility of CO2 and quartz in the numerical experiments. Significant fluctuations of fluid pressure and high-velocity hydrothermal pulse are found once rock is fractured by high-pressure fluids. The fluid pressure drop induced by hydraulic fracturing could cause a 9% decrease of quartz solubility. This amount of quartz deposition may not cause a significant decrease in rock permeability. The fluid pressure decrease after hydraulic fracturing also reduces solubility of CO2 by 36% and increases pH. Because an increase in pH would cause a major decrease in solubility of tungsten, the fluid pressure drop accompanying a hydraulic fracturing process facilitates wolframite precipitation. Our numerical experiments provide insight into the mechanisms precipitating wolframite at the tungsten deposits in the Nanling Range as well as other metals whose solubility is strongly dependent on pH.
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DOI：
--
发表时间：
2011
期刊：
Geological Journal of China Universities
影响因子：
--
作者：
Huo Dong-quan
通讯作者：
Huo Dong-quan
DOI：
10.1016/c2013-0-12927-3
发表时间：
1997-03
期刊：
--
影响因子：
--
作者：
C. Yew
通讯作者：
C. Yew
矿化计算流体动力学的一些基本问题：综述
影响因子：
3.9
作者：
Zhao, Chongbin;Reid, L. B.;Regenauer-Lieb, R.
通讯作者：
Regenauer-Lieb, R.
影响因子：
--
作者：
D. Dempsey;J. Rowland;G. Zyvoloski;R. Archer
通讯作者：
D. Dempsey;J. Rowland;G. Zyvoloski;R. Archer
影响因子：
--
作者：
X. Cui;P. Nabelek;Mian Liu
通讯作者：
X. Cui;P. Nabelek;Mian Liu