| Summary: | 9th SCAR Open Science Conference and XXXVI SCAR Meetings. Hobart, Tasmania, Australia. 31 July - 11 August 2020 [EN] The separation of the Australian Plate with respect to the Antarctic Plate during the Cenozoic was the origin of the development of the Tasmania Passage. In order to better understand how the continental fragmentation and the plates drift occurred, it is important to establish the stress orientation and regime that have acted during the formation of this passage. With the aim to contribute to the knowledge of the tectonic evolution of the Tasmanian Passage, approximately 1000 faults distributed in 44 sites located in rocks of ages between the Cambrian and the Quaternary have been measured in Tasmania. The fault population analysis has been carried out using the methods of Etchecopar, y-R, Right Dihedral and Stress Inversion. The fault orientation analysis shows a predominant orientation ESE-WNW and secondary directions NE-SW, NW-SE and N-S. Considering the faults movement sense, 313 dextral, 194 sinistral, 422 normal and 62 reverse faults have been identified. Dextral faults show an ESE-WNW orientation. Sinistral faults have a predominant orientation N-S. The most of the dextral and sinistral fault planes dips are subvertical. Normal faults have a main NW-SE orientation and a NE-SW secondary direction with a modal dip value of 65°. Reverse faults have a predominant NE-SW direction with two modal dip values of 35° and 70° respectively. The σ1 orientation shows a dominant NW-SE direction. Moreover, another common stress regime is characterized by a preferentially NE-SW σ3 orientation (with σ1 vertical). The σy direction is dominantly NW-SE, although it shows a secondary mode with NE-SW orientation
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