We analyzed seismicity linked to the 2014 phreatic eruption of Mount Ontake, Japan, on 27 September 2014. We first relocated shallow volcano tectonic (VT) earthquakes and long-period (LP) events from August to September 2014. By applying a matched-filter technique to continuous waveforms using these relocated earthquakes, we detected numerous additional micro-earthquakes beneath the craters. Th...

[1] Large earthquakes can trigger distant earthquakes in geothermal areas. Some triggered earthquakes happen while the surface waves pass through a site, but others occur hours or even days later. Does this prolonged seismicity require a special mechanism to store the stress from the seismic waves that differs from ordinary aftershock mechanisms? These questions have driven studies of long-rang...

Operational earthquake forecasting in the Uniform California Earthquake Rupture Forecast, version 3 (UCERF3) model will be implemented using the Epidemic Type Aftershock Sequence (ETAS) model. Parameter values for the ETAS model are determined by fitting that model to the recent instrumental earthquake catalog. A grid search is done, and the loglikelihood is used as a measure of fit to estimate...

S U M M A R Y We present a strategy for estimating the recurrence times between large earthquakes and associated seismic hazard on a given fault section. The goal of the analysis is to address two fundamental problems. (1) The lack of sufficient direct earthquake data and (2) the existence of ‘subgrid’ processes that can not be accounted for in any model. We deal with the first problem by using...

north-east khorasan is one of the most active regions in the world because of is setting on the alpine-himalayan belt. historical and geological backgrounds suggest that this region has experienced many destructive earthquakes throughout history. compared with the historical background, the seismicity of the region, in the present century, is better known both from the macroseismic and instrume...

We invoke a metric to quantify the correlation between any two earthquakes. This provides a simple and straightforward alternative to using space-time windows to detect aftershock sequences and obviates the need to distinguish main shocks from aftershocks. Directed networks of earthquakes are constructed by placing a link, directed from the past to the future, between pairs of events that are s...

Dear Editors, Pfenninger et al. [1] presented in a recent research paper an outline of a curriculum covering medical student disaster education. Their work demonstrated an interdisciplinary format and multi-experiential structure for a curriculum. However, understanding the rationales for including such a component in a medical curriculum might need to be clearly highlighted. Furthermore, many ...

A three-dimensional seismic wave speed model in the Kanto region of Japan was developed using adjoint tomography for application in the effective reproduction of observed waveforms. Starting with a model based on previous travel time tomographic results, we inverted the waveforms obtained at seismic broadband stations from 140 local earthquakes in the Kanto region to obtain the Pand S-wave spee...