tehran as the biggest metropolitan of iran is located in the areas that are at high-risk of earthquake. what increases tehran's vulnerability toward earthquake is the urban physical expansion in vaious dimensions. since the analysis of the mentioned expansion is a solution to many urban problems, the effects of tehran expansion in increasing vulnerability to earthquake has been surveyed in...

[1] We investigate seismicity near faults in the Southern California Earthquake Center Community Fault Model. We search for anomalously large events that might be signs of a characteristic earthquake distribution. We find that seismicity near major fault zones in Southern California is well modeled by a Gutenberg-Richter distribution, with no evidence of characteristic earthquakes within the re...

The Mw 7.9 Denali fault earthquake ruptured segments of the Susitna Glacier, Denali, and Totschunda faults in central Alaska, providing a unique opportunity to look for intermediate-term (weeks to months) responses of active volcanoes to shaking from a large earthquake. The Alaska Volcano Observatory (AVO) monitors 24 volcanoes with seismograph networks. We examined one station per volcano. Dig...

We present a new three-dimensional inventory of the southern San Francisco Bay area faults and use it to calculate stress applied principally by the 1989 M = 7.1 Loma Prieta earthquake and to compare fault seismicity rates before and after 1989. The major high-angle right-lateral faults exhibit a different response to the stress change than do minor oblique (right-lateral/thrust) faults. Seismi...

One way to probe earthquake nucleation processes and the relation between stress buildup and seismicity is to analyze the sensitivity of seismicity to stress perturbations. Here, we report evidence for seasonal strain and stress (~2–4 kPa) variations in the Nepal Himalaya, induced by water storage variations which correlate with seasonal variations of seismicity. The seismicity rate is twice as...

Fluid injection into deep wellbores can increase pore pressure, reduce effective stress, and trigger earthquakes. The extent of the seismogenic response to injection provides insight into how close faults are to failure in the injection-affected area. The seismogenic response to injection operations in hydrocarbon basins is examined in California and Oklahoma. Changes in spatial and temporal se...

Earthquakes far from tectonic plate boundaries generally exploit ancient faults, but not all intraplate faults are equally active. The North American Great Plains exemplify such intraplate earthquake localization, with both natural and induced seismicity generally clustered in discrete zones. Here we use seismic velocity, gravity and topography to generate a 3D lithospheric density model of the...

The trifurcation area of the San Jacinto fault zone has produced more than 10% of all earthquakes in southern California since 2000, including the June 2016 Mw (moment magnitude) 5.2 Borrego Springs earthquake. In this area, the fault splits into three subparallel strands and is associated with broad VP /VS anomalies. We synthesize spatiotemporal properties of historical background seismicity a...

We present the results of relocating 17,544 hypocenters determined from data recorded during the 2016 Kumamoto Earthquake sequence, during the interval between April 14, 2016, and August 31, 2016. For this, we used a doubledifference relocation method to constrain high-resolution hypocenter locations by cross-correlation differential times as well as the NIED Hi-net catalog differential times. ...

Changes in seismicity rates, whether of tectonic or of induced origin, can readily be identified in regions where background rates are low but are difficult to detect in seismically active regions. We present a novel method to identify likely induced seismicity in tectonically active regions based on short-range spatiotemporal correlations between changes in fluid injection and seismicity rates...