A surprising increase in seismicity started in and around Monticello Reservoir, South Carolina in December 1996, and by the end of 1999, over 700 earthquakes with 0.4 ML 2.5 had been located. This seismicity occurred in a new hypocentral region and filled the gaps in earlier seismicity at depths shallower than 2 km. The seismicity occurred in four episodes each with at least one earthquake of m...

Continental intraplate seismicity seems often episodic, clustered, and migrating. The observed seismicity shows both spatial clustering in seismic zones and scattering across large plate interiors, temporal clustering followed by long periods of quiescence, and migration of seismicity from one seismic zone to another. Here, we explore the complex spatiotemporal patterns of intraplate seismicity...

Using the simple ETAS branching model of seismicity, which assumes that each earthquake can trigger other earthquakes, we quantify the role played by the cascade of triggered seismicity in controlling the rate of aftershock decay as well as in the overall level of seismicity in the presence of a constant external seismicity source. We show that, in this model, the proportion of triggered seismi...

Modern, powerful techniques for the residual analysis of spatialtemporal point process models are reviewed and compared. These methods are applied to California earthquake forecast models used in the Collaboratory for the Study of Earthquake Predictability (CSEP). Assessments of these earthquake forecasting models have previously been performed using simple, low-power means such as the L-test a...

To develop spatially continuous seismicity models (earthquake probability distributions) from a given earthquake catalog, the method of kernel estimation has been suggested. Kernel estimations with a global (spatially invariant) bandwidth deal poorly with earthquake hypocenter distributions that have different spatially local features. For example, a typical earthquake catalog has several areas...

We investigate upper plate stressing during the earthquake cycle in a subduction segment, using three-dimensional (3-D) elastic models to address the effects of strongly heterogeneous coupling along strike of the interplate interface. We show how heterogeneity controls the locations and mechanisms of seismicity in the upper plate. Oblique subduction segments, two from the Aleutians (Andreanof I...

An approach to compute optimum seismic design parameters is presented. It is based on the optimization of the expected present value of the total cost, which includes the initial cost of structures as well as the cost due to earthquakes. Different types of seismicity models are considered, including one for characteristic earthquakes. Uncertainties are included in some variables to observe the ...

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...

Induced seismicity has been observed near Monticello Reservoir, South Carolina, since December 1977. Deployment of a seismic network before impoundment allowed for detection and accurate location of pursuant seismicity since its inception. Corroborative fault-plane solutions, together with geological and borehole data on fracture orientations, made it possible to determine the structures associ...