Migration of micro-earthquakes during cyclic operation of Underground Gas Storage and the Changdao earthquake swarm
Dr. Baoshan Wang (School of Earth and Space Sciences, University of Science and Technology of China) Abstract: The distribution of earthquakes is controlled by the stress state and material properties. And the migration of earthquakes can be used to infer the changes in subsurface stress or medium properties. In this presentation, we will introduce two case studies of seismicity migrations related respectively to the Hutubi Underground Gas Storage (UGS) in Junggar Basin and the Changdao earthquake swarm occurred in the Bohai Sea. We first use the matched and filter technique to detect more events than the local catalog. And then we relocate the detected events using double difference method with waveform cross-correlation-based differential travel-times. Micro-earthquakes clearly migrate outward from the UGS during the cyclic operation, the migration may result from the stress transfer during multiple injection and extraction. The seismicity during Changdao earthquake swarm unilaterally migrated south-west accompanied by some bursts along several conjugate faults. We suggest that fluid diffusions are responsible for the earthquake migration in Changdao.
Our paper (Mukuhira et al., 2017 JGR) is honored as paper award from Japanese society for rock mechanics (JSRM). Thank you for your support on our research activity. Also we sincerly appreciate Prof. Ishida (ex Kyoto Univ.) for recommendation.
Our collaborative research proposals have been accepted by ifs, Tohoku Univ. Thanks for warm support! We will be in pursuit of collaborative project.
FY2019: Collaborative Research Project 2019, Institute of Fluid Science, Tohoku University JPY 397k/y (PI) Project title: Estimation of fracture permeability by integrating microseismic observational data and reservoir engineering modeling. Project partner: Dr. Justin Rubinstein (USGS), Dr. Jack Norbeck (UCB)
FY2019: Collaborative Research Project 2019, Institute of Fluid Science, Tohoku University JPY 374k/y (co-PI) Project title: Application of core-based inversion to reconstruct stress field in an underground geoscience laboratory. Project partner: Dr. Xiadong Ma (ETH Zurich)
After Davos induced seismicity workshop at Davos, I stopped at ETH and gave a talk about Mukuhira et al., 2018 (GJI).
Speaker:Yusuke Mukuhira, Assistant Professor of Tohoku University, Institute of Fluid Science Time: 2-3:30pm,March 11th, 2019 Room: NO F47 Title: Constraining of Focal Mechanisms of Induced Seismicity Using Borehole Logging Information