Sedimentology and Image-Log Analysis of the
Jurassic, Deltaic Plover Formation, Browse
Basin, North West Shelf, Australia
The Plover Formation in the Browse
Basin (Australian North
West Shelf) is an Early to Middle Jurassic, syn-rift, deltaic system which
hosts reservoirs currently targeted for gas exploration and development.
Depositional history and paleogeographical evolution of the Plover Formation in
the Calliance field have been established through integrated analysis of core,
borehole image log and wireline log data in conjunction with biostratigraphic
data. Six facies associations have been identified through facies analysis of
core and interpreted as tidally influenced channel- and tidal channel-fill
complexes (FA1-FA2), crevasse splays and interchannel marshes (FA3), tidal bars
and flats (FA4), shoreface (FA5) and offshore-transition to offshore (FA6)
depositional settings. Analysis of FMI and FMS images reveals sedimentological
features that are not visible in core that provide additional information
regarding depositional processes and environments. Core-based and image log
analysis shows that the Plover Formation in the Calliance area was deposited on
a tidally influenced delta plain to delta front. Tidal processes exerted a
fundamental control on the development of porosity and permeability with
highest reservoir quality associated with FA1. Combining sedimentological
results with biostratigraphic data has been used to identify five second-order
stratigraphic units bounded by surfaces with sequence-stratigraphic
significance (~5-9 Ma duration). Integration of the depositional model with
sediment dispersal interpretations from paleocurrent data derived from image
log analysis, and identification of major synsedimentary faults from seismic
data, is being used to interpret reservoir geometry of the Plover Formation in
the Calliance field which is complicated by volcanic and volcaniclastic facies
recording active volcanism during deltaic deposition.
AAPG Search and Discovery Article #90142 © 2012 AAPG Annual Convention and Exhibition, April 22-25, 2012, Long Beach, California