Investigation of behavior of engineered geothermal reservoirs by super-resolution mapping techniques

地热能是未来最具潜力的能源之一，因为它在地球上分布广泛，对地球安全、清洁、环保。工程地热系统，包括干热岩（HDR），热湿岩（HWR）和增强型地热系统（EGS），是未来发电的希望。然而，与水力压裂相关的储层的行为尚未被清楚地理解，因此这在工程地热系统的开发中带来了不确定性/风险。在该项目中，研究了用于描绘微震云内部结构的微震技术，然后将微震活动信息与地质信息和岩石力学相结合，以解释/理解储层中的物理学。主要研究结果如下：1.在Soutls，Fenton-Hill，Rosemanowes，Ogachi和Hijiori收集的数据集通过超分辨率映射技术进行了重新分析。对微观地震构造的位置和方向进行了估计，并对其行为（滑动、应力条件等）进行了分析。也被估计。研究了超分辨率映射技术的变化，以减少映射中的不确定性/误差。通过室内模拟花岗岩断裂剪切滑动试验，研究了地震活动与先存断裂位置、方向等地质信息的关系。

Geothermal energy is one of the most potential energy source in future, because it is widely distributed on the earth, safe, clean and environmentally friendly to the earth. Engineered geothermal systems, which includes hot dry rock (HDR), hot wet rock (HWR) and enhanced geothermal systems (EGS), are promising for electrical power generation in future. However, behavior of reservoirs associated with hydraulic fracturing has not been clearly understood, and hence this brings uncertainty/risk in the development of engineered geothermal systems. In this project, microseismic techniques for delineation of structures inside the microseismic cloud was investigated, then informations from microseismicity was combined with geological information and rock mechanics to interpret/understand physics in the reservoir. Major results from this project are,1. Data sets collected at Soutls, Fenton-Hill, Rosemanowes, Ogachi, and Hijiori were re-analyzed by super-resolution mapping techniques. Location and orientation of microscopic seismic structures were estimated and their behavior (slip, stress conditions etc.) were also estimated. Variation of super-resolution mapping techniques was investigated to reduce uncertainty/error in mapping.2. Relationship between seismic activity and geological information including location and orientation of preexisting fracture was investigated by tests in laboratory simulating a shear slip of fracture in granite.