This review paper summarizes recent advances and challenges in the assessment of rock behavior and performance in deep low-permeability and high-temperature geothermal reservoirs. Geothermal energy systems for electricity production target deep rock between ca. 2 km and 5 km depth to obtain sufficiently elevated temperatures. Rock permeability enhancement faces many challenges, and therefore the development of Enhanced Geothermal Systems (EGS) still represents a pioneering effort. The potential and advantage of EGS above conventional geothermal reservoirs is its independence of the location that supplies sufficient heat and fluid. Several issues prevent the successful application of EGS technology. First, the effects of non-uniform in-situ stresses and loading history on rock fracturing are not well understood. Second, the role of rock anisotropy, heterogeneity and thermal effects on rock properties in the design of hydraulic fracturing operations is not clear. Third, the reduction of induced seismicity effects raises safety and public acceptance issues. This manuscript formulates outlines for future research directions. Specifically, the recommendations focus on the development of tools for better understanding and mitigating problems, which occur during stimulation of deep geothermal reservoirs.

这篇综述文章总结了在深部低渗透和高温地热油藏中岩石行为和性能评估方面的最新进展和挑战。用于发电的地热能系统的目标是大约在大约之间的深层岩石。2 公里和5 公里深度以获得足够高的温度。岩石渗透率的提高面临许多挑战，因此增强地热系统（EGS）的开发仍代表着开拓性的努力。EGS在常规地热储层之上的潜力和优势在于其独立于提供足够热量和流体的位置。有几个问题阻碍了EGS技术的成功应用。首先，对于岩石破裂的非均匀原地应力和加载历史的影响尚不十分清楚。其次，在水力压裂作业设计中，岩石的各向异性，非均质性和热效应对岩石性质的作用尚不清楚。第三，减少诱发地震影响会引发安全性和公众接受度问题。该手稿为将来的研究方向制定了大纲。具体而言，建议着重于开发工具，以更好地理解和缓解深部地热储层增产过程中出现的问题。