Tarim Basin: Petroleum
Geology and Future Discovery Potential
Zhang, Guangya1, Wen-zhi Zhao2,
Xin-yuan Zhao3 (1) PetroChina, Beijing, China (2) Research Institute
of Petroleum Exploration and Development, PetroChina, Beijing, China (3) Tarium
Oilfield, Petrochina Company LTD, Xinjiang, China
The Tarim Basin, covering a total area
of 560,000 km2, is a large composite basin consisting of a Paleozoic marine
cratonic basin and a Meso-Cenozoic continental foreland basin. The sedimentary
succession in the basin is up to 18,000 m in thickness. Primary source rocks of
the Tarim Basin are the Cambrian-Lower
Ordovician, the Middle-Upper Ordovician marine source rocks, the
Carboniferous-Permian continental-oceanic transitional facies source rocks, and
the Triassic-Jurassic continental source rocks. The dominant reservoir rocks
consist of Cambrian-Ordovician carbonate and Paleozoic-Tertiary clastic rocks.
In the cratonic basin, the main traps are anticlinal drapes, carbonate
subcrops, lithologic traps and stratigraphic traps. The foreland basin is
dominated by structural traps. Fault blocks and stratigraphic traps are limited
to the slope of the foreland basin. The Tarim basin is rich both in oil and gas
resources. Oil is mainly concentrated in the cratonic basin, particularly on
the Tabei and Central uplifts.