Tuesday, 28 August 2007
2.PS-52
Structure of the Central Terror Rift, Western Ross Sea, Antarctica
Jerome Hall1, Terry J. Wilson1, and Stuart A. Henrys2. (1) School of Earth Sciences, Ohio State University, 125 S. Oval Mall, Columbus, OH 43210-1522, (2) GNS Science, 1 Fairway Drive, Avalon, Lower Hutt, New Zealand
The Terror Rift, located within the Western Ross Sea, has the most recent fault activity within the West Antarctic Rift System (Cooper et al., 1987). New seismic data over the central Terror Rift better resolves the architecture and timing of rift activity. Evidence from our new analysis shows the Terror Rift to be composed of segmented, offset sub-basins, bounded by transverse structures coeval with the onset of rifting. The central Terror Rift underwent east-west rifting, without a significant transtensional component. Rift-related volcanism, including feeder dikes and subvolcanic intrusions, post-date the main phase of rift development in the central Terror Rift. All rift deformation post-dates 17 Ma. There were multiple phases of faulting, and faults cutting the seafloor surface suggest possible modern activity.