Deception Island is an acti.

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; Antarctic Peninsula; Bransfield Strait; Deception Island; South Shetland Islands; The Antarctic; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.572.8437; http://pubs.usgs.gov/of/2007/1047/ea/of2007-1047ea025.pdf

Summary Deception Island (62°59 ’ S, 60°41 ’ W) is an active volcano located in the Bransfield Strait between the Antarctic Peninsula and the South Shetland Islands. It is composed of rocks that date from <0.75 Ma to historical eruptions (1842, 1967, 1969 and 1970). In January 2005 an extensive seismic survey took place in and around the island, to collect high quality data for a P wave velocity tomography study. A total of 66 land and 14 ocean bottom seismometers were deployed, and more than 5000 airgun shots were fired. A preliminary three-dimensional inversion of the travel times resolves strong velocity contrasts down to 5 km depth. The most striking feature is the low seismic velocity beneath the caldera floor which represents an extensive region of magma beneath a sediment-filled basin. A low velocity zone to the east of Deception Island corresponds to seafloor sedimentary deposits, and high velocities to the northwest are interpreted as the crystalline basement of the South Shetland Islands platform. We observe NE-SW and NW-SE trends in the tomographic image that are compatible with the regional tectonic directions and suggest that