Marine Geothermal Research in Taiwan: An Overview

Marine Geothermal Research in Taiwan: An Overview

Taiwan's unique marine geologic setting, marked by complex tectonic features and active hydrothermal systems, offers critical insights into Earth's geological processes and renewable energy resources. This paper reviews the progress in marine geothermal research in Taiwan, including the development of instruments, field measurements, data analysis, thermal modeling, and interpretations, laying the groundwork for future exploration and development. The use of Lister-Type Heat Probes (LTHP) and Miniature Temperature Loggers (MTLs) in heat probe measurements has been pivotal in acquiring highly accurate seafloor temperature data. These measurements provide valuable insights into regional thermal structures and fluid migration pathways around Taiwan. In addition to direct temperature measurements, indirect methods based on bottom-simulating reflections (BSRs) have been developed and applied to infer sub-seafloor temperatures, contributing to a comprehensive understanding of marine geothermal gradients. The results underscore the diverse geothermal gradients across different tectonic regions offshore SW Taiwan, influenced by tectonic activities and sedimentation rates. The presence of extremely high heat flows in the Southern Okinawa Trough suggests active hydrothermal systems around offshore northeastern Taiwan, while the detection of heat pulses at Turtle Island may indicate landslides and groundwater migration events. The influence of topographic effects on thermal structures has also been observed, necessitating corrections for accurate geological interpretations. The potential of marine geothermal research for practical applications, such as the exploration of gas hydrates, hydrothermal minerals, and renewable energy resources, is immense. However, to fully harness these benefits, continued efforts are paramount. These efforts should focus on bridging data gaps, enhancing spatial coverage, and integrating diverse marine surveying data. The advancements in measurement and monitoring techniques, coupled with the support of government policies, will pave the way for sustainable development and efficient utilization of geothermal energy resources. Furthermore, the ongoing geological surveys and long-term monitoring of seafloor stability are indispensable for understanding and mitigating geohazards.