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WESTERN
AUSTRALIAN DIVISION August 2008 Divisional Meeting Date: Tuesday 5th August Time: Venue: Geography Lecture Theatre 1, Geology-Geography
Building, The University of Western Australia, Nedlands Download a map indicating parking options, or
check out the venue with Google
Maps Speaker:
Dr Peter Eadington
(CSIRO Petroleum) Topic: Reflections
on fluid Inclusions, petrophysics, structural
geology and petroleum systems: addressing some challenges in the search for
oil in Drinks and nibbles will be served before and after
the talk Abstract: The important role of
fluids in petroleum geology and the study of petroleum systems results in
synergistic relationships between data from fluid inclusions about palaeo-oil and palaeo-formation
water and petrophysics, structural geology,
geochemistry, and hydrology. Petrophysical
calculations that transform log data to pseudo-permeability and
pseudo-capillary pressure guide where to select samples to test for oil
migration pathways or palaeo-oil zones using fluid
inclusion techniques. In turn the salinity of inclusion water by thermometric
measurements informs the evaluation of resistivity of irreducible water, used
in the Archie equation for water saturation in hydrocarbon reservoirs. The volume
of original oil in place represented by a palaeo-oil
zone in gas-saturated reservoir is evaluated by structural interpretation of
the volume of the trap and petrophysical evaluation
of the saturation of palaeo-oil. The time a tilted palaeo-oil water contact was level can be evaluated by
structural back stripping of overlying strata. Identifying watersaturated reservoir traps that do or do not have palaeooil zones provides a pattern that can be
interpreted in terms of fault kinematics to deduce structural forms favourable
for retention of hydrocarbons. The
biomarker composition of inclusion oil is interpreted for the age and
sedimentary environment of source rock and for the maturity and alteration of
oil. These are used to identify source pods that can be used in kinetic
models of oil generation, and in expected quality of oil in prospects. The
salinity of palaeo-formation water from measurement
of fluid inclusions reveals the presence of ambient and exotic fluids in
sedimentary basins. Flow of exotic fluids is often a useful marker of the relative
timing of fill-spill events in the fluid history of a reservoir. West Australian
Geologist (WAG) Bi-monthly
newsletter of the Western Australian Division of the Geological
Society of Australia Inc. Number 472: August – September 2008 (717 kb PDF file) AGM Minutes Minutes
of 2008 AGM (206 kb PDF file) Minutes of 2007 AGM
(432 kb PDF file) Minutes
of 2006 AGM (300 kb PDF file) Website maintained by: Peter Haines |
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