Structure and prospectivity of the northern Australian margin collision zone revealed by new regional seismic data
A. Tripathi A , W. Jones A and A. Williams APGS Reservoir.
The APPEA Journal 52(2) 704-704 https://doi.org/10.1071/AJ11118
Published: 2012
Abstract
The interpretation of recently acquired regional-deep, 2D seismic data across the Timor/Tanimbar Trough has provided a new insight into the structure of this continent/arc collision zone. This data is mostly recorded to 10–12 secs with an 8 km dual sensor streamer, providing increased resolution and improved penetration compared with vintage data, particularly in the deeper part of the section.
A major improvement in the new data is the imaging of the Australian continental margin succession continuously from the Australian side of the Timor-Tanimbar Trough for a distance of a few tens of km underneath the accretionary prism on the northwest side of the trough.
Structures observed in the accretionary prism itself include fold and thrust belts, imbricate thrusts and extensional half grabens. The detachment surface at its base may provide a regional seal for traps involving Jurassic and Triassic reservoirs in underlying thrusts for which there is some evidence on the seismic data.
The improved visibility of the Mesozoic succession below the accretionary prism allows possible Jurassic source rocks to be followed to the northwest below a growing overburden to a depth at which maturity may be expected. There is also a graben, probably including a greater Jurassic thickness, under the Timor Trough.
Anand Tripathi graduate from the Maharaja Sayajirao University of Baroda, India. He has more than 15 years of industry experience, starting in 1989 at ONGC as a geologist. He then obtained a PhD from the University of Waikato, New Zealand. He joined PGS-Reservoir in 2008 as senior geoscientist. Member: PESA, ASEG, FESA. |
Will Jones graduated in geology from Cambridge University in 1970 and holds a PhD (based on mapping volcanic rocks in Kenya) from London University. After teaching at the University of Ghana, he started his oil industry career at Esso Exploration as a seismic interpreter. Since then, he has worked in the oil industry for 20 years with Phillips Petroleum, the UK Dept of Energy, Robertson Research, and now PGS Reservoir as well as periods as an independent consultant. His experience covers exploration in several parts of the world, notably Europe, Africa, and now Australia. He is presently manager of the Perth branch of PGS Reservoir where he supervises the interpretation of PGS’s multiclient data sets. |
Adrian Williams is an exploration consultant, presently working as an advisor geophysics at Petroleum GeoServices. He graduated with a BSc (geology) (hons) from ANU in 1975, a diploma of education from Murdoch University in 1988, and an MBA from UNE in 1998. He started his resources career as a geologist in an underground nickel mine in WA, but he soon changed to petroleum geophysics at Shell in 1980. From various downsizings and takeovers, he then worked for a variety of companies including Delhi Petroleum, Bond Energy, Hadson Energy, and Apache Energy before finally starting PetroSearch (Training and Consulting) in 1996 where he now divides his time between consulting and providing industry training courses. Member: PESA. |
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