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Site content related to keyword: "seismic station"

Stefanie Baxter interviewed by local media regarding earthquake in Japan.

Stefanie Baxter, research associate with the Delaware Geological Survey, was interviewed March 11 by Channel 6 Action News, Channel 16 WBOC and the News Journal, regarding the 8.9 magnitude earthquake in Japan.

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Catalog of Delaware Earthquakes Spreadsheet

Catalog of Delaware Earthquakes Spreadsheet

The occurrences of earthquakes in northern Delaware and adjacent areas of Pennsylvania, Maryland, and New Jersey are well documented by both historical and instrumental records. Over 550 earthquakes have been documented within 150 miles of Delaware since 1677. One of the earliest known events occurred in 1737 and was felt in Philadelphia and surrounding areas. The largest known event in Delaware occurred in the Wilmington area in 1871 with an intensity of VII (Modified Mercalli Scale). The second largest event occurred in the Delaware area in 1973 (magnitude 3.8 and maximum Modified Mercalli Intensity of V-VI). The epicenter for this event was placed in or near the Delaware River. Sixty-nine earthquakes have been documented or suspected in Delaware since 1871.

Sussex County Emergency Operation Center (SCOM) Seismic Station

Sussex County Emergency Operation Center (SCOM) Seismic Station. The seismometer, located on the property of the Sussex County Emergency Operation Center, is positioned on the Beaverdam Formation. The Beaverdam Formation is a very coarse sand with beds of fine to medium sand. It is interpreted to be a Pliocene fluvial to estuarine deposit.

Delaware Emergency Management Agency (DEMA) Seismic Station

Delaware Emergency Management Agency (DEMA) Seismic Station. The seismometer, located at the Delaware Emergency Management Agency, is located on the Columbia Formation. The Columbia Formation is a fine to coarse, feldspathic quartz sand with varying amounts of gravel. It is primarily a body of glacial outwash sediment deposited in a cold climate during the middle Pleistocene.

White Clay Creek State Park (NED) Seismic Station

White Clay Creek State Park (NED) Seismic Station. The seismometer, located in White Clay Creek State Park, is positioned on the Wissahickon Formation. The Wissahickon Formation is an extensive sequence of pelitic and psammitic gneisses interlayered with amphibolites. With few exceptions, most of the amphibolite layers are less than 30 feet thick. The rocks have been metamorphosed to upper amphibolite facies and isoclinally folded. The formation is located within the Wilmington North, Kennett Square, West Grove, Newark West, and Newark East U. S. Geological Survey 7.5-minute quadrangles.

Brandywine Creek State Park (BWD) Seismic Station

Brandywine Creek State Park (BWD) Seismic Station. The seismometer located at Brandywine Creek State Park is positioned on the Wissahickon Formation. The Wissahickon Formation is an extensive sequence of pelitic and psammitic gneisses interlayered with amphibolites. With few exceptions, most of the amphibolite layers are less than 30 feet thick. The rocks have been metamorphosed to upper amphibolite facies and isoclinally folded. The formation is located within the Wilmington North, Kennett Square, West Grove, Newark West, and Newark East quadrangles.

Bellevue State Park (BVD) Seismic Station

Bellevue State Park (BVD) seismic network station. The seismometer located at Bellevue State Park is placed on the Brandywine Blue Gneiss. The Brandywine Blue Gneiss is the new name given to the granulite-facies felsic gneisses in the Wilmington Complex. Informally called the “blue rocks,” this unit is a medium- to coarse-grained, lineated (pinstriped), two-pyroxene gneiss with variable quartz content and thin, discontinuous mafic layers, pods, and schlieren. The pinstriping and the massive nature of the rock suggest the rock is intrusive; however, deformation and recrystallization have obscured original igneous features.