We have developed an elastic finite element model in order to study the role of the different forces acting on the northwestern part of the Central American Volcanic Arc and the Chortis Block. We present synthetic focal mechanisms, maps of tectonic regime, and strain crosses to analyze the results. The models show that to achieve the observed state of stress on the volcanic arc, the arc must be modeled as a lithospheric weak zone. Also, the forces related to the eastward drift of the Caribbean plate must be higher than those related to the subduction of the Cocos plate. The coupling on the subduction interface must be low, with or without slip‐partitioning due to the obliquity of the subduction at the trench. At Guatemala the western edge of the Chortis block is pinned against North America, even with low trench‐normal forces, making the triple junction between the Cocos, North American, and Caribbean plates a zone of diffuse deformation. The extension in the western part of the Chortis block, from Guatemala to the Honduras depression, is explained by the geometry of the North American‐Caribbean plate boundary and the direction of motion of the Caribbean plate with respect to North America. The direction of extension in the Chortis block is always E‐W regardless of the magnitude of the applied forces, and the main part of the deformation is absorbed between the Ipala graben and the Honduras depression, both features being consistent with our models.
Betic Cordillera INSAR Coulomb stress transfer Seismic hazard Active tectonics Intersegment zoneOn May 11 th 2011, a Mw 5.2 earthquake stroke the city of Lorca in the SE Spain. This event caused 9 fatalities, 300 injuries and serious damage on the city and the surrounding areas. The Lorca earthquake occurred in the vicinity of a region bounding two well-known segments of a large active fault, the Alhama de Murcia fault (AMF). The Lorca earthquake offers a unique opportunity to study how strain is accommodated in an inter segment region of a large strike slip fault. We map recent tectonic structures in the epicentral region and we use radar interferometry to analyze the coseismic deformation. Combining these data with seismological ob servations of Lorca seismic sequence we first model the source of the earthquake. Then we analyze the influ ence of our preferred model in the adjacent segments by Coulomb failure stress modeling. The proposed earthquake source model suggests that this event ruptured an area of -4x3 km within the complex structure that limits the Gofiar-Lorca and Lorca-Totana segments of the AMF. The induced static stress change on the adjacent segments of the fault represents a seismic cycle advance equivalent to 200 to 1000 years of tectonic loading.
The Quaternary Active Faults Database of Iberia (QAFI) is an initiative lead by the Institute of Geology and Mines of Spain (IGME) for building a public repository of scientific data regarding faults having documented activity during the last 2.59 Ma (Quaternary). QAFI also addresses a need to transfer geologic knowledge to practitioners of seismic hazard and risk in Iberia by identifying and characterizing seismogenic fault-sources. QAFI is populated by the information freely provided by more than 40 Earth science researchers, storing to date a total of 262 records. In this article we describe the development and evolution of the
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.