Multibeam data from the "Wanganui Neotectonics - Back-arc Extension" voyage (TAN0105) of the R/V Tangaroa. Multibeam data was acquired on the Narrows Basin of Cook Strait as part of this voyage. The voyage was undertaken as part of the "Extensional Back-arc Processes" project of the "Active Seabed Processes" FRST programme. The objectives of the programme are to determine the contemporaneous processes of extensional faulting, subsidence and sedimentation in the Wanganui Bight and Bay of Plenty, to compare the mechanisims of extension, potential seismicity of offshore faluts, and the influence of sealevel cycles on sediment-tectonic interactions at opposite ends of the back-arc region of the Hikurangi subduction zone. Survey Leader: Geoffroy Lamrache Organisations: NIWA Bathymetric Instrument: Simrad EM300 30kHz Multibeam Navigation Instrument: DGPS Ports: Wellington to Wellington