Systematization of active faults for the assessment of the seismic hazard
- 25 February 2012
- journal article
- Published by Pleiades Publishing Ltd in Russian Journal of Pacific Geology
- Vol. 6 (1), 42-51
- https://doi.org/10.1134/s1819714012010101
Abstract
A systematization of active faults has been developed based on the progress of scientists from the leading countries in the world in the study of seismotectonics and seismic hazard problems. It is underlain by the concept of the fault-block structure of the geological-geophysical environment governed by the interaction of differently oriented active faults, which are divided into two groups—seismogenic and nonseismogenic faults. In seismogenic fault zones, the tectonic stress accumulated is relieved by means of strong earthquakes. Nonseismogenic fault zones are characterized by creep displacement or short-term, oscillatory, and reciprocal movements, which are referred to local superintense deformations of the Earth’s crust (according to the terminology used by Yu.O. Kuz’min). For a situation when a strong earthquake happens, a subgroup of seismodistributing faults has been identified that surround the seismic source and affect the distribution of the seismic waves and, as a consequence, the pattern of the propagation of the coseismic deformations in the fault-block environment. Seismodistributing faults are divided into transit and sealing faults. Along transit faults, secondary coseismic effects (landfalls, landslides, ground fractures, liquefaction, etc) are intensified during earthquakes. In the case of sealing faults, enhancement of the coseismic effects can be observed on the disjunctive limb nearest to the epicenter, whereas, on the opposite limb, the intensity of such effects appreciably decreases. Seismogenic faults or their systems are associated with zones of earthquake source origination (ESO), which include concentrated seismicity regions. In such zones, each earthquake source is related to the evolution of a fault system. ESO zones also contain individual seismogenic sources being focuses of strong earthquakes with M of ≥5.5 in the form of ruptures, which can be graphically represented in 2D or 3D as a surface projection of the source. Depending on the type of data based on which they are identified, individual seismogenic sources are divided into geological-geophysical and macroseismic sources. The systematization presented is the theoretical basis for and the concept of the relational database that is being developed by the authors as an information system for the generation of seismotectonic GIS projects required for the subsequent analysis of the seismic hazard and the assessment of the probability of the origination of macroseismic earthquake effects in a predetermined location.Keywords
This publication has 10 references indexed in Scilit:
- A new electronic map of active faults for southeastern SiberiaDoklady Earth Sciences, 2010
- Activity rating of Pliocene–Quaternary faults: a formalized approach (example of the Baikal rift system)Russian Geology and Geophysics, 2010
- Paleoearthquakes in the Pribaikalie: methods and results of datingGeodynamics & Tectonophysics, 2010
- The Database of Individual Seismogenic Sources (DISS), version 3: Summarizing 20 years of research on Italy's earthquake geologyTectonophysics, 2008
- Gravity effects caused by moderate earthquakes: role of local fault patternRussian Geology and Geophysics, 2007
- Probabilistic Seismic Hazard Assessment for JapanPure and Applied Geophysics, 2006
- The investigation of potential earthquake sources in peninsular Italy: A reviewJournal of Seismology, 2001
- Seismotectonic zoning in east-central Italy deduced from an analysis of the Neogene to present deformations and related stress fieldsGSA Bulletin, 1994
- New empirical relationships among magnitude, rupture length, rupture width, rupture area, and surface displacementBulletin of the Seismological Society of America, 1994
- Seismic-Wave Attenuation Associated with Crustal Faults in the New Madrid Seismic ZoneScience, 1990