Coseismic surface deformation imaged through interferometric synthetic aperture radar (InSAR) measurements was used to estimate the fault geometry and slip distribution of the 2017 Mw 6.5 Ormoc earthquake along a creeping segment of the Philippine Fault on Leyte Island. Our best fitting faulting model suggests that the coseismic rupture occurred on a fault plane with high dip angle of 78.5° and strike angle of 325.8°, and the estimated maximum fault slip of 2.3 m is located at 6.5 km east‐northeast of the town of Kananga. The recognized insignificant slip in the Tongonan geothermal field zone implies that the plastic behavior caused by high geothermal gradient underneath the Tongonan geothermal field could prevent the coseismic failure in heated rock mass in this zone. The predicted Coulomb failure stress change shows that a significant positive Coulomb failure stress change occurred along the SE segment of central Philippine Fault with insignificant coseismic slip and infrequent aftershocks, which suggests an increasing risk for future seismic hazard.

The process of extracting natural gas from gas hydrate‐bearing sediments (GHBS) may yield significant sand influx due to the metastable nature of GHBS. Selecting appropriate sand control media is vital to addressing the challenges caused by excessive sand production. This study proposes a protocol called holding coarse expelling fine particles (HCEFP) for sand control design. The protocol aims to provide a new optimization method for screen mesh size selection for clayey silt hydrate reservoirs. Detailed optimizing procedures of proper candidate screen mesh sizes in hydrate exploitation well in clayey silt hydrate reservoirs are depicted based on the HCEFP. Then, the site W18, which is located in the Shenhu area of the northern South China Sea, is taken as an example to illustrate the optimization procedure for screen mesh size selection. The results reveal that complete solid retention via a standalone screen is rarely beneficial as high clay contents can adversely affect wellbore productivity due to excessive plugging. Screen aperture size selection for clayey silt hydrate wells should strike a balance between retaining coarser particles and avoiding screen blockage by the relatively fine particles. Furthermore, longitudinal heterogeneity of the PSDs also increases the difficulties associated with sand control design. Multistage sand control optimization is necessary in hydrate production wells. For Site W18, we recommend that the entire production interval can be divided into two subintervals for multistage sand control operations.

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