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[1] We argue that key features of thrust earthquake triggering, inhibition, and clustering can be explained by Coulomb stress changes, which we illustrate by a suite of representative models and by detailed examples. Whereas slip on surface-cutting thrust faults drops the stress in most of the adjacent crust, slip on blind thrust faults increases the stress(More)
After the 1987 Whittier Narrows and 1994 Northridge earthquakes revealed that blind thrust faults represent a significant threat to metropolitan Los Angeles, a network of 250 continuously recording global positioning system (GPS) stations was deployed to monitor displacements associated with deep slip on both blind and surface faults. Here we augment this(More)
Magma intrusions and eruptions commonly produce abrupt changes in seismicity far from magma conduits that cannot be associated with the diffusion of pore fluids or heat. Such 'swarm' seismicity also migrates with time, and often exhibits a 'dog-bone'-shaped distribution. The largest earthquakes in swarms produce aftershocks that obey an Omori-type(More)
A model of stress transfer implies that earthquakes in 1933 and 1952 increased the Coulomb stress toward failure at the site of the 1971 San Fernando earthquake. The 1971 earthquake in turn raised stress and produced aftershocks at the site of the 1987 Whittier Narrows and 1994 Northridge ruptures. The Northridge main shock raised stress in areas where its(More)
The 28 June Landers earthquake brought the San Andreas fault significantly closer to failure near San Bernardino, a site that has not sustained a large shock since 1812. Stress also increased on the San Jacinto fault near San Bernardino and on the San Andreas fault southeast of Palm Springs. Unless creep or moderate earthquakes relieve these stress changes,(More)
Large earthquakes trigger very small earthquakes globally during passage of the seismic waves and during the following several hours to days, but so far remote aftershocks of moment magnitude M ≥ 5.5 have not been identified, with the lone exception of an M = 6.9 quake remotely triggered by the surface waves from an M = 6.6 quake 4,800 kilometres away. The(More)
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(More)
Standardized plastic analogues simulating an endodontically treated maxillary central incisor root were used to investigate the resistance to root fracture in endodontically treated teeth. Three different post and core systems were used: (1) cast post and core, (2) Para-Post Plus post, and (3) Flexi-Post post. The core build-up material selected in this(More)
Currently available impression materials were not designed for disinfection or sterilization, and it is conceivable that disinfectants may adversely affect impressions. This study evaluated the accuracy and dimensional stability of polyether (Permadyne/Impregum) and polyvinyl siloxane (Express) impression materials retained by their adhesives in two(More)
Tokyo and its outlying cities are home to one-quarter of Japan's 127 million people. Highly destructive earthquakes struck the capital in 1703, 1855 and 1923, the last of which took 105,000 lives. Fuelled by greater Tokyo's rich seismological record, but challenged by its magnificent complexity, our joint Japanese-US group carried out a new study of the(More)