High-frequency observations and source parameters of microearthquakes recorded at hard-rock sites

Edward Cranswick; Robert Wetmiller; John Boatwright

doi:10.1785/bssa0750061535

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High-frequency observations and source parameters of microearthquakes recorded at hard-rock sites

Edward Cranswick·Robert Wetmiller·John Boatwright

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Abstract

We have estimated the source parameters of 53 microearthquakes recorded in July 1983 which were aftershocks of the Miramichi, New Brunswick, earthquake that occurred on 9 January 1982. These events were recorded by local three-component digital seismographs at 400 sps/component from 2-Hz velocity transducers sited directly on glacially scoured crystalline basement outcrop. Hypocentral distances are typically less than 5 km, and the hypocenters and the seven digital seismograph stations established all lie essentially within the boundaries of a granitic pluton that encompasses the faults that ruptured during the main shock and major aftershocks. The P-wave velocity is typically 5 km/sec at the surface and at least 6 km/sec at depths greater than about 1 km.

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Bulletin of the Seismological Society of America Article

Source-reported bounding extent: 46.792931091368445° to 47.268437041340945° latitude; -65.91437956310268° to -65.12336393810268° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Edward Cranswick, Robert Wetmiller, John Boatwright. 1985. High-frequency observations and source parameters of microearthquakes recorded at hard-rock sites. https://doi.org/10.1785/bssa0750061535

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