关键词: 构造演化, 油气分布特征, 主控因素, 西北大陆架, 澳大利亚

Abstract: Based on the analysis of tectonic evolution and petroleum geology，the author summarized the oil and gas distribution
features of northwest shelf of Australia，and discuss the main controlling factors of hydrocarbon accumulation. The results
show that the hydrocarbon distribution of northwest shelf of Australia are divisional in plane，oil mainly occurs in NW trend
narrow rifts formed during the late Jurassic，while gas mainly distributed in the outer highs adjacent to those rifts. Vertically，
hydrocarbon principally occurs in Mesozoic series with a stratified feature，and gas is concentrated in Triassic and Jurassic
reservoirs while oil mainly occurred in Cretaceous and upper formations. Hydrocarbon accumulation of northwest shelf of
Australia is principally controlled by source rock，structural background，big delta sedimentary systems，regional seal and
later preservation conditions. Source rock property and distribution led to the appearance of“rich in gas and poor in oil”
of northwest shelf Australia and controlled the oil and gas distribution. Big delta sedimentary systems and fine regional seals
provided excellent source-reservoir-seal assemblages，and determined the concentration layers of hydrocarbon. Besides，uplifts
and highs adjacent to sags are always the favorable areas with all sorts of traps developed.

Key words: tectonic evolution, oil and gas distribution features, main controlling factors, northwest shelf, Australia