EXCALIBUR - Example of Coherent Amplified Light for In-Borehole Microseismic Recording

随着全球努力提高可再生能源发电的比例，地热能最近受到了关注，因为它能够同时产生热能和电能，而不依赖于风能或太阳能输出等环境因素。地热发电站从地壳深处提取热量，那里的岩石面积通常达到240摄氏度。在“热岩”地区创建地热发电站需要在地壳中钻孔，并为水通过炎热的基岩创造通道。这项钻探活动需要仔细的监测，以确保正确创建预期的水道，并满足对微地震活动的严格环境监测(特别是在英国)，以确保不会因这一深部钻探而引发更大的地震事件。除了监测地热站在其生命周期内的持续健康状况外，还使用带有微地震传感器的垂直地震剖面(VSP)来实现这种监测。Avalon Sciences Limited(ASL)是VSP系统的世界领先制造商，过去35年来，VSP系统主要用于石油和天然气行业的勘探。在ASL的内部研发中心，传感器设计的创新使他们的电子和光学VSP系统能够在200°C下可靠地运行。然而，这些系统不能在过高的地热井中长期存活。在这个项目中，ASL将开发一种定制的全光学(无电子)微地震VSP原型，能够运行到300°C，用于地热行业的长期微地震监测。

With the global drive to increase the proportion of energy generation through renewable sources, geothermal energy has attracted recent attention for its ability to produce both heat and electrical energy without a dependence on environmental factors such as wind or solar output. A geothermal power station extracts heat deep from within the Earth's crust where areas of rock typically reach 240°C.Creating geothermal power stations in "hot rock" areas requires drilling boreholes into the Earth's crust and creating pathways for water to flow through hot bedrock. This drilling activity requires careful monitoring to ensure the intended water pathways are correctly created and to satisfy strict environmental monitoring (especially in the UK) for micro-seismic activity to ensure that larger seismic events are not induced by this deep drilling. Vertical Seismic Profiling (VSP) with micro-seismic sensors is used to achieve this monitoring in addition to monitoring the ongoing health of a geothermal station during its lifetime.Avalon Sciences Limited (ASL) is a world-leading manufacturer of VSP systems which have been used predominantly in the oil & gas industry for exploration for the past 35 years. With ASL's in-house research & development centre, innovation in sensor design has enabled reliable operation of their electronic and optical VSP systems at 200°C. However, these systems cannot survive for long in the excessively high temperature geothermal wells.In this project, ASL will develop a bespoke all-optical (no electronics) micro-seismic VSP prototype capable of operating up to 300°C for long-term micro-seismic monitoring for the geothermal energy industry.