
	Where results make sense

Topic: Induced seismicity

Related Topics

Earthquake

Seismic wave

Landslide

Pressure

Plate tectonics

Carbon dioxide

Deforestation

In the News (Fri 11 Dec 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	NORSAR - Induced seismicity
		Induced seismicity describes earthquakes that in one way or another are related to human activity.
		Earthquakes are mainly induced in three antropogenic settings, (1) in mines, (2) in connection with large water reservoirs and (3) in oil or gas fields where hydrocarbons are extracted.
		Reservoir induced seismicity in connection with large hydropower dams has been well known for at least 60 years, and induced seismicity in connection with ore mining has a history of at least 100 years.
	www.norsar.no /seismology/induced (840 words)

	NORSAR services: Induced seismicity
		Reservoir-induced seismicity in connection with large hydropower dams has been well known for at least 60 years, and induced seismicity in connection with ore mining has a history of at least 100 years.
		The problems relating to induced seismicity have been known from oil and gas fields since the 1920s, and was 30 years later thoroughly studied at an oil field near Wilmington, California, where the oil production triggered a series of damaging earthquakes.
		Induced seismicity can involve large and damaging earthquakes as in Uzbekistan or in California, however, more frequently we observe micro seismicity or `cracking' in an exploited reservoir as shown for an oil field in the figure.
	www.norsar.no /seismology/services/induc.html (269 words)

	Induced seismicity - Wikipedia, the free encyclopedia
		In seismology, induced seismicity refers to earthquakes that are caused by human activity.
		Most induced seismicity is of an extremely low magnitude, and in many cases, human activity is merely the trigger for an earthquake that would have occurred naturally in any case.
		Reservoir-induced seismic events can be relatively large compared to other forms of induced seismicity.
	en.wikipedia.org /wiki/Induced_seismicity (174 words)

	USGS - Review of seismic-hazard issues associated with the Auburn Dam project, Sierra Nevada foothills, California (Site not responding. Last check: 2007-10-20)
		The potential for reservoir-induced seismicity, which is the triggering of earthquakes by the physical processes that accompany the impoundment of large reservoirs, was recognized during the seismic hazard studies for the original Auburn Dam.
		Most examples of induced seismicity occur in regions of low tectonic loading rates dominated by normal faulting as is the case in the Sierran foothills, or strike-slip faulting (Scholz, 1990).
		Aside from Oroville, which may have had reservoir-induced seismicity, there are six existing large dams in the Sierran foothills that have the height and reservoir volume necessary to place them in the worldwide classification of dams that have the potential to produce reservoir induced seismicity.
	ca.water.usgs.gov /archive/reports/auburn/induced.html (1240 words)

	17 March 1997 (Site not responding. Last check: 2007-10-20)
		The spatio-temporal and energetic characteristics of induced seismicity and its relationship with the natural and technogenic triggering processes under study were investigated, and databases of temporal variation of the various geophysical fields — potential triggers were created.
		Results show that, although the seismicity of the study region exhibits multifractal patterns both in space and in time, the stronger multifractality of the catalog corresponding to the period of the MHD runs is due to the spatio-temporal clustering of the aftershocks of a strong (m=6.28) event.
		Objective is to develop/adjust mathematical tools for the study of the phenomenon of induced seismicity taking into account of the variety potential of natural and manmade triggers; to understand the physics underlying the coupling between the electromagnetic and stress fields (faulting/seismicity induced by electromagnetic impacts) and construct a rheological model of fracturing (faulting) incorporating it.
	www.ingv.it /ing/ing712/INTAS99www/report/finalReport/EMQfinalreport.htm (3999 words)

	Seismicity in mines: a review (Site not responding. Last check: 2007-10-20)
		Seismicity is the rock mass response to deformation and failure.
		A rockburst is defined as a mining- induced seismic event that causes damage to openings in the rock.
		Seismic monitoring is an important tool for many mines today, and is therefore reviewed including a description of the most common seismological terms that are used to describe seismicity.
	epubl.luth.se /1402-1536/2004/22 (353 words)

	[No title] (Site not responding. Last check: 2007-10-20)
		Evans was also the first to suggest the idea that fluid injection might be used in seismically active areas to initiate small-scale fault movement, effectively releasing stress in a non-damaging manner and reducing the risk of a large earthquake.
		This type of induced seismicity is typified by the Khibing Massif area in the Kola Peninsula of Russia.
		From this brief discussion one can see that seismicity induced by fluid extraction does not fit our simple model, and a complete explanation of complex mechanisms such as poroelastic theory is beyond the scope of this paper.
	www.umich.edu /~gs265/induced.htm (4114 words)

	Earthquake - Open Encyclopedia (Site not responding. Last check: 2007-10-20)
		It is usually possible to identify a point from which the earthquake's seismic waves appear to emanate.
		Earthquakes such as these, that are caused by human activity, are referred to by the term induced seismicity.
		Caused great and unexpected destruction of freeway bridges and flyways in the San Fernando Valley, leading to the first major seismic retrofits of these types of structures, but not at a sufficient pace to avoid the next California freeway collapse in 1989.
	open-encyclopedia.com /Earthquake (1047 words)

	[No title]
		In particular, seismic events with non-shearing components are expected to occur in close vicinity to the mining faces, where favourable conditions for generation of shear failures with tensile components are present.
		Triggering of seismic events by unloading of the Earth's surface in case of deep pits is discussed by means of the Mohr diagram with the Coulomb failure criterion.
		The potential for induced seismicity appears also by loading effect of big external spoil heaps during mining and interaction of loading and pore-pressure effects due to the filling of pits with water after the exploitation of mines.
	www.irsm.cas.cz /irsm/acta/A9_100c.html (3705 words)

	[No title] (Site not responding. Last check: 2007-10-20)
		Induced seismicity in a salt mine environment evaluated by a coupled continuum-discret modelling.
		This project focus on two main complementary axis: the validation of induced seismicity monitoring techniques in salt mine environments, and the numerical modelling of deformation and failure mechanisms with their associated acoustic emissions, the induced microseismicity.
		To keep the elasto-brittle behaviour of the competent layers where most seismic damage is expected and in order to directly compare the acoustic emission events, we use the Particle Flow Code (PFC, Itasca Cons.) based on the discrete element method.
	www.ipgp.jussieu.fr /~mercerat/research_int.html (595 words)

	Seismology Education
		Reservoir induced seismicity is a transitory phenomenon which will occur either immediately after filling of the reservoir, or after a delay of a few years.
		Even for those reservoirs that show a correlation between earthquake activity and water level, reservoir induced seismicity does not continue indefinitely as it is limited by the available tectonic energy.
		Induced earthquakes at reservoirs that have experienced delayed triggering may be much deeper, perhaps as deep as ten to twenty kilometres.
	www.seis.com.au /Basics/Dams.html (636 words)

	Untitled Document
		Seismicity associated with the Shivaji Sagar lake formed by the Koyna dam is considered to be a classic example of earthquake activity triggered by reservoirs.
		It is believed that the pore pressure changes induced by the reservoir reduces the strength of the rocks leading to failure along a major fault zone in the vicinity of the dam.
		Seismic zonation map of a country is a guide to the seismic status of a region and its susceptibility to earthquakes
	www.cessind.org /earthquakes_inindia.htm (1538 words)

	ORBIT SPECIAL: TECTONIC WEAPONS (Site not responding. Last check: 2007-10-20)
		Changes in the seismicity regime are observed during water-storage reservoir flooding; in the regions where intensive oil and gas extraction takes place; during deep-well disposal of wastes, etc. Also stated is the fact that underground nuclear explosions may effect spatio-temporal seismicity distribution and initiate its increase at separations up to 200-2,000 km.
		The external impact is assumed to initiate release of seismic energy accumulated in the media during the tectonic processes in the form of relatively weak earthquakes thus lowering the threshold level of strong catastrophic earthquakes.
		Therewith, the seismic energy is released in a form of relatively weak earthquake thus lowering the threshold level of strong catastrophic ones.
	www.cyberspaceorbit.com /tectonic_weapons.html (2723 words)

	Geofisica Internacional (Site not responding. Last check: 2007-10-20)
		The parameters conducive to reservoir-induced seismicity such as height, volume, time lag from the filling to the occurrence of a significant earthquake and maximum magnitude, were generally taken from the data published by Gupta (1992).
		Talwani and Acree (1985) have studied the seismic hydraulic diffusivity of reservoir-induced seismicity from the growth of aftershocks; but this aspect could not be examined due to lack of data for many reservoirs.
		(1988) identified a type of induced seismicity in terms of temporal and spatial characteristics, featuring rapid response in which the seismicity is closely correlated with changes in water level.
	www.unam.mx /serv_hem/revistas/fisica/1997/01/srivasta.html (2414 words)

	Earthquakes in Mines as a Natural Laboratory of Earthquake Processes Posters - Seismology [S]
		Mining-induced seismicity includes events directly triggered by blasting that are assumed to involve fresh fracturing of rock as well as those induced over longer timescales that have been hypothesized to be dominated by frictional slip.
		During the excavation of the tunnel network at the 420m level of the URL an extensive data-set of induced seismicity data was recorded from which an understanding of the rock mass response was obtained.
		This seismicity was concentrated in zones of `excavation disturbance' around the tunnels, and the activity level was observed to fall away to almost nothing a few days after the excavation was complete in each tunnel section.
	www.agu.org /meetings/fm04/fm04-sessions/fm04_S41B.html (4117 words)

	Modelling of Stress Development & Fault Slip in & (Site not responding. Last check: 2007-10-20)
		Induced seismicity related to gas production has become a growing problem in the Netherlands in the past two decades.
		Induced seismicity is generally assumed to be the result of induced reactivation of discontinuities in the subsurface.
		It is very likely that the seismic events are the result of reactivation of existing discontinuities (like faults) in or near the reservoirs.
	www.coronetbooks.com /books/mode4547.htm (183 words)

	Earthquake Hazards Program: Routine United States Mining Seismicity: STATE-BY-STATE LIST OF MINING REGION
		The special analysis suggests that the mislocations are a consequence of an unfavorable azimuthal distribution of stations recording the events, combined with the misidentification of Pg-phases as Pn-phases at stations to the north of the epicenters.
		Induced seismic events of similar magnitude are also listed for this area in earthquake catalogs of the USGS/NEIC (see Mining-induced events in the earthquake catalogs of the USGS/NEIC).
		In addition, regionally recorded seismic signals are produced by roof-collapses that are deliberately induced by longwall mining in a large underground mine (Walter and others, 1996).
	wwwneic.cr.usgs.gov /neis/mineblast/sources.html (2898 words)

	3 (Site not responding. Last check: 2007-10-20)
		In particular, to study the mechanism and main features of microearthquake generation in deformed rock specimens subjected to electromagnetic excitation in a wide range of frequencies and amplitudes; to investigate the effects of the rock’s mineral composition and fluid content on the dynamic (spatio-temporal) and energetic characteristics of the generated microearthquakes.
		Objective: to develop/adjust mathematical tools for the study of the phenomenon of induced seismicity taking account of the variety potential of natural and manmade triggers; to understand the physics underlying the coupling between the electromagnetic and stress fields (faulting/seismicity induced by electromagnetic impacts) and construct a rheological model of fracturing (faulting) incorporating it.
		Data from earthquake-prediction experiments in which seismically active regions of Central Asia were subjected to regular EM sounding with the aid of a magneto-hydrodynamic (MHD) generator will be analysed by means of advanced statistical tools while taking account of the presence of other potential triggers, natural and manmade, to reveal possible interrelations.
	www.ingv.it /ing/ing712/INTAS99www/workpro.html (4584 words)

	Citebase - Testing self-organized criticality by induced seismicity
		Not all perturbations, however, trigger seismic activity; this is also compatible with the SOC hypothesis which embodies naturally the existence of large heterogeneities in the stress field.
		In conclusion, the properties of induced seismicity and their rationalization in terms of the SOC concept provide further evidence that potential seismic hazards extend over a much larger area than that where earthquakes are frequent.
		Grasso, J.-R., Fluids and seismic instabilities: implication for the mechanical behavior of the uppercrust, doctorat d'ï¿½tat thesis, Univ. of Grenoble, Grenoble, France, 1993
	citebase.eprints.org /cgi-bin/citations?archiveID=oai:arXiv.org:cond-mat/9810190 (3866 words)

	Baisch, S (Site not responding. Last check: 2007-10-20)
		Consequently, it is assumed that the geometry of the fracture network was not changed during fluid injection and induced seismicity solely occurs due to effective normal stress lowering consistent with observed source mechanisms.
		J of energy radiated seismically: A major part of hydraulic energy might be converted to potential energy of the ground water level due to upward migrating fluid.
		This is consistent with the observation that none of the larger induced events is followed by aftershock series which would be expected if coseismic processes had noticeable perturbed the local stress field.
	sdac.hannover.bgr.de /dgg2002/abstracts/BP/Baisch_V.htm (516 words)

	Ewa Glowacka - CICESE (Site not responding. Last check: 2007-10-20)
		Her research interests include seismic hazard, deformations and induced seismicity; geothermal fields and mines.
		Seismic hazard estimate based on the extracted deposit volume and bimodal character of seismic ativity, Gerlands Beitr.
		An attempt of continuous evaluation of seismic hazard induced by deposit extraction for the Robert field in the Gottwald mine in Kladno.
	sismologia.cicese.mx /glowacka/glowacka.htm (605 words)

	Poroelastic Stressing and Induced Seismicity (Site not responding. Last check: 2007-10-20)
		These earthquakes are clearly separated from tectonic seismicity occurring in the Pyrenees, 25 km to the southwest.
		Segall (1989) suggested that poroelastic stressing, associated with volumetric contraction of the reservoir rocks, is responsible for induced seismicity associated with fluid extraction.
		Accurate determination of focal mechanisms of the induced events would allow a more rigorous test of the poroelastic model and could lead to important inferences about the crustal stress state.
	pangea.stanford.edu /~segall/lacq.html (350 words)

	World Rivers Review, June 1997 (Site not responding. Last check: 2007-10-20)
		Reservoirs are believed to have induced five out of the nine earthquakes on the Indian peninsula in the 1980s which were strong enough to cause damage.
		Reservoirs can both increase the frequency of earthquakes in areas of already high seismic activity and cause earthquakes to happen in areas previously thought to be seismically inactive.
		When the pressure of the water in the rocks increases, it acts to lubricate faults which are already under tectonic strain, but have been prevented from slipping by the friction of the rock surfaces.
	www.irn.org /pubs/wrr/9706/ris.html (500 words)

	A Comparative Study Of Natural And Man-Induced Seismicity In The Yanqing-Huailai Basin And The Haicheng Area ... (Site not responding. Last check: 2007-10-20)
		Abstract: Natural earthquakes and mine-induced seismicity are health, life, and economic hazards.
		Seismic wave studies from such sources provide a mechanism for understanding local propagation path effects and constraints upon source mechanism dynamics.
		The geographic focus of this investigation is in two areas, the Yanqing-Huailai Basin around Beijing and northeast China along the Tan-Lu fault near the area of the 1975 Haicheng earthquake.
	citeseer.ist.psu.edu /551086.html (218 words)

Try your search on: Qwika (all wikis)