On March 31, 2020, an Mw 6.5 earthquake struck near Stanley, Idaho. More than 35% nondouble-couple component in long-period point-source solutions indicate a more complex source slip on planar fault. Using integrative analysis of seismological and geodetic data, we find that the Stanley ruptured pair opposing-dip faults offset by 10-km-wide step, including unmapped northern subfault with predom...

Geoscientists from the Coso Operating Company, EGI-Utah, GeoMechanics International, and the U.S. Geological Survey are cooperating in a multi-year study to develop an Enhanced Geothermal System (EGS) in the Coso Geothermal Field. Key to the creation of an EGS is an understanding of the relationship among natural fracture distribution, fluid flow, and the ambient tectonic stresses that exist wi...

Recent numerical simulation of tsunami propagation proposed a new hypothesis about the origin of the 1771 tsunami that devastated the southwest Ryukyu district of Japan; a slip of the East Ishigaki Fault, a 44kmlong fault lying 50km off the east coast of Ishigaki Island, might be the cause of the 1771 tsunami. The present study is to test this hypothesis through visual observation by means of t...

We determined the centroid moment tensor (CMT) solutions of earthquakes that occurred along the North Anatolian fault (NAF) beneath the Sea of Marmara and the Aegean Sea, using data obtained from Turkey’s broadband seismograph network. The CMT solution of the 2014 Aegean Sea earthquake (Mw 6.9) represents a strike-slip fault, consistent with the geometry of the NAF, and the source-time function...

On the route to a spatio-temporal geoscience information system, an appropriate data model for geo-objects in space and time has been developed. In this model, geo-objects are represented as sequences of geometries and properties with continuous evolution in each time interval. Because geomodeling software systems usually model objects at specific time instances, we want to interpolate the geom...

Within the subseafloor, methane hydrates form within the gas hydrate stability zone (GHSZ). Two areas within the Gulf of Mexico (GOM) were investigated in this study: Keathley Canyon and Atwater Valley. The GOM contains an underlying petroleum system and deeply buried, yet dynamic salt deposits. Salt tectonics and fluid expulsion upward through the sediment column lead to the formation of fract...

[1] The tectonic evolution of Mars has been driven primarily by the interaction of Tharsisinduced loading stresses with a uniform contractional stress field, leading to global assemblages of graben and wrinkle ridges. Until recently, strike-slip faults have appeared to be largely absent from the tectonic record. We here present evidence for a new set of Noachian to Early Hesperian strike-slip f...

[1] Motivated by observations in the 2008Mw 7.9 Wenchuan earthquake, we study effects of systematic changes in the principal stress orientation along the fault strike on rupture dynamics and ground motion using a 3‐D finite‐element method. Based on Anderson’s theory of faulting, we set up the initial stress field with rotations in stress orientations along strike for a dynamic rupture model of ...

Strike-slip faults may be traced along thousands of kilometers, e.g., the San Andreas Fault (USA) or the North Anatolian Fault (Turkey). A closer look at such continental-scale strike faults reveals localized complexities in fault geometry, associated with fault segmentation, secondary faults and a change of related hazards. The North Anatolian Fault displays such complexities nearby the mega c...

[1] We present the results of a series of 3-D boundary element calculations to investigate the effects of oceanic transform faults on stress state and fault development at adjacent mid-ocean ridge spreading centers. We find that the time-averaged strength of transform faults is low, and that on time scales longer than a typical earthquake cycle transform faults behave as zones of significant we...