ZHONG Yuyun, researcher, majors in reservoir-induced earthquake, E-mail: 598247337@qq.com
We attempt to apply rock physics-related techniques to study the mechanism of reservoir-induced earthquakes, use the fluid substitution method to calculate the rock porosity in Shanxi reservoir and employ the pore pressure diffusion equation to estimate the pore pressure diffusion coefficient in reservoir area. The results show that: 1) The porosity is maximized in the shallow part of reservoir area within 2 km depth, followed by the southeastern segment of seismogenic fault and minimized in northwestern segment. This distribution feature has a good correspondence with the grouped activity of earthquake sequence, where higher porosity area with better permeability conditions is the region where the first earthquake occurred after reservoir impoundment. 2) The pore pressure diffusion coefficients of earthquake swarms in 2002, 2006, and 2014 are 5.83 m2/s, 8.19 m2/s, and 0.41 m2/s, respectively. This difference has a good consistency with the local variability in rock porosity distribution in reservoir area, indicating that higher pore pressure diffusion coefficient correspond to higher rock porosity. 3) The diffusion rate in epicentral zone is uneven, and the epicentral zone in 2014 was under a higher stress critical state compared to those in 2002 and 2006.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |