MARINE GEOLOGY INTCRNATIONAL JOURNAL of marine

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; Antarctic Peninsula; Bridgeman; South Shetland Islands; The Antarctic; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.464.4041; http://www.vliz.be/imisdocs/publications/314.pdf

The Bransfield Basin is a young active rift basin located between the northern margin o f the Antarctic Peninsula and the South Shetland Islands margin. Deception and Bridgeman islands divide the Bransfield Basin in three subbasins, the western, central and eastern. Specific morpho-tectonic features and sediment fill differentiate each subbasin. The structure and geodynamic evolution of the Central Bransfield Basin, which is in a stage of incipient seafioor spreading, have been investigated in detail from a dense grid of single-channel seismic reflection data. The Central Bransfield Basin is dominated by two families o f normal faults which are oriented northeast and northwest. The NE-trending faults define three graben systems that are roughly parallel to the basin axis. In an across-basin direction, the mean trend o f this family o f faults ranges from N71 (the graben system nearest to the Antarctic Peninsula) over N64 (the intermediate graben system), to N53 (the graben system nearest to the South Shetland Islands). The NW-trending family of faults is responsible for the deepening o f the basin from southwest to northeast. Both families o f faults define the overall Central Bransfield Basin structure, resulting in a complex division of the basin floor. Additionally, tens of volcanic edifices are located on the basin floor, the larger ones being associated to the NW-trending faults. Interaction of tectonics and sedimentation give place to the differentiation o f three tectonostratigraphic units, TU I, TU2 and TU3 (from oldest to youngest). TU I occupies