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

随着全球努力增加通过可再生能源发电的比例，地热能最近因其能够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而引起关注。地热发电站从地壳深处提取热量，其中岩石区域通常达到240°C。在“热岩”地区建立地热发电站需要在地壳中钻孔，并为水流过热基岩创造通道。该钻探活动需要仔细监测，以确保正确创建预期的水道，并满足对微震活动的严格环境监测（特别是在英国），以确保该深层钻探不会引发更大的地震事件。除了在地热站的使用寿命期间监测地热站的持续健康状况外，还使用带有微地震传感器的垂直地震剖面（VSP）来实现这一监测。阿瓦隆科学有限公司（ASL）是世界领先的VSP系统制造商，在过去的35年里，VSP系统主要用于石油和天然气行业的勘探。凭借ASL的内部研发中心，传感器设计的创新使其电子和光学VSP系统能够在200°C下可靠运行。然而，这些系统无法在温度过高的地热威尔斯井中长期使用。在该项目中，ASL将开发一种定制的全光学（无电子）微地震VSP原型，能够在高达300°C的温度下运行，用于地热能源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.