
TY  - JOUR
A1  - O'Brien, G.W. 
A1  - Reeves, C.V. 
A1  - Milligan, P.R. 
A1  - Morse, M.P. 
A1  - Alexander, E.M. 
A1  - Willcox, J.B. 
A1  - Yunxuan, Zhou 
A1  - Finlayson, D.M. 
A1  - Brodie, R.C. 
T1  - NEW IDEAS ON THE RIFTING HISTORY AND STRUCTURAL ARCHITECTURE OF THE WESTERN OTWAY BASIN: EVIDENCE FROM THE INTEGRATION OF AEROMAGNETIC, GRAVITY AND SEISMIC DATA
JF  - The APPEA Journal
JO  - The APPEA Journal
Y1  - 1994
VL  - 34
IS  - 1
SP  - 529
EP  - 554
KW  - 
UR  - https://doi.org/10.1071/AJ93042 
N2  - The integration of high resolution, image-processed aeromagnetic data with regional geological, magnetic, gravity and seismic data-sets has provided new insights into the structural architecture, rifting history, and petroleum potential of the western onshore and offshore Otway Basin, south-eastern Australia.Three principal structural directions are evident from the magnetic data: NS, NE-ENE and NW-WNW. The structural fabric and regional geological data suggest that the rifting history of the basin may have taken place in two distinct stages, rather than within a simple rift-to-drift framework. The initial stage, from 150 to ~120 Ma, took place within a stress regime dominated by NW-SE extensional transport, similar to that of the basins within the Great Australian Bight to the west. ENE-striking extensional rift segments, such as the Crayfish Platform-Robe Trough and the Torquay Sub-Basin, developed during this period, contemporaneous with the deposition of thick sediments of the Early Cretaceous (Tithonian-Hauterivian) Crayfish Subgroup. In other parts of the basin, NW-striking rift segments, such as the Penola, and perhaps Ardonachie, Troughs onshore, developed within a strongly trans-tensional (left-lateral strike-slip) environment. At ~120 Ma, the regional stress field changed, and the Crayfish Subgroup-aged rift segments were reactivated, with uplift and block faulting extending through to perhaps 117 Ma. Rifting then recommenced at about 117 Ma (contemporaneous with the deposition of the Barremian-Albian Eumeralla Formation), though the extensional transport direction was now oriented NNE-SSW, almost perpendicular to that of the earlier Crayfish Subgroup rift stage. This later rift episode ultimately led to continental breakup at ~96 Ma and produced the &apos;traditional&apos; normal fault orientations (NW-SE to WNW-ESE) throughout the Otway Basin. 
ER  -

