Sources of Stress in Intraplate Seismic Zones

Jan 15, 2022 research, seismotectonics

One study area includes the New Madrid Seismic Zone in the Central U.S.

The main goal of this project is to compute magnitudes and spatial distribution of stresses responsible for earthquakes occurring in regions far from plate boundaries based on seismically imaged heterogeneities in mantle. Also considered are the effects of known geological structures like layers of different kinds of rock or major fault zones. Computed stress distributions in terms of the maximum horizontal stress orientation and the magnitude of maximum shear stress can be compared with the observed seismicity. The study area we have been working on include the New Madrid Seismic Zone in the central US, the Charlesvoix Seismic Zone in eastern Canada and the Korean peninsular.

A study on the Charlesvoid Seismic Zone. The impact crater and Paleozoic rift faults together increases differential stress in the areas of high seismicity. For more details, see [(Fadugba et al., JGR, 2019)](https://cerigeodyn.netlify.app/publication/fadugba-effects-2019/) — A study on the Charlesvoid Seismic Zone. The impact crater and Paleozoic rift faults together increases differential stress in the areas of high seismicity. For more details, see (Fadugba et al., JGR, 2019)

A study on the seismic zones in the Central and Eastern US. The upper mantle heterogeneities clearly contribute to differerntial stresses in the known seismic zones. Discrepancy between the predicted and the observed faulting styles are attributed to stress sources not included in this study. For more details, see [(Saxena et al., GJI, 2021)](https://cerigeodyn.netlify.app/publication/saxena-seismicity-2021/) — A study on the seismic zones in the Central and Eastern US. The upper mantle heterogeneities clearly contribute to differerntial stresses in the known seismic zones. Discrepancy between the predicted and the observed faulting styles are attributed to stress sources not included in this study. For more details, see (Saxena et al., GJI, 2021)

A study on the stress contributions from the mantle heterogeneity and the regional east-west compression to the seismicity in the Korean peninsular. The second invariant of deviatoric stresses arising from the regional compression and the mantle flow driven by the mantle heterogeneity are seen correlated with the shallow (< 15 km depth) seismicity in the region. For more details, see [(Lee et al., GJI, 2022)](https://academic.oup.com/gji/advance-article/doi/10.1093/gji/ggab527/6488384) — A study on the stress contributions from the mantle heterogeneity and the regional east-west compression to the seismicity in the Korean peninsular. The second invariant of deviatoric stresses arising from the regional compression and the mantle flow driven by the mantle heterogeneity are seen correlated with the shallow (< 15 km depth) seismicity in the region. For more details, see (Lee et al., GJI, 2022)

Intrplate Earthquakes Intraplate Seismic Zones Seismic Tomography Stress PyLith ASPECT

Sources of Stress in Intraplate Seismic Zones

Eunseo Choi

Professor in Geophysics