Yamin Z.,Changan University |
Yamin Z.,Ministry of Education Key Laboratory of Western Chinas Mineral Resources and Geological Engineering |
Petroleum Exploration and Development | Year: 2010
The oil and gas exploration in Baiyinchagan Sag, Erlian Basin, has been 30 years, with no breakthrough until 2003. In the area of being thought with no oil, some high-yielding prolific fields and high-quality scale reserves have been discovered, by reexamining the old data to establish a new reservoir formation pattern, and with new exploration concepts, from resource evaluation, major structural background optimization and big sand body searching and its combination with structural background, to applying 3D seismic technology and other technologies to identify the traps of small structures, faulted blocks and sand bodies. Many new fields have been discovered, such as Sanghe, West Sanghe, Daerqi, West Daerqi, West Wengte and Xilinhaolai, with proved oil in place up to several tens of million tons and an additional annual capacity of 10×104 t. The exploration history and experience in Baiyinchagan Sag will throw new light for risk exploration of other old sags. © 2010 Research Institute of Petroleum Exploration & Development, PetroChina.
Yang G.,Ministry of Education Key Laboratory of Western Chinas Mineral Resources and Geological Engineering |
Yang G.,Changan University |
Li Y.,Ministry of Education Key Laboratory of Western Chinas Mineral Resources and Geological Engineering |
Li Y.,Changan University |
And 5 more authors.
International Geology Review | Year: 2014
U-Pb zircon geochronological, geochemical, and whole-rock Sr-Nd isotopic analyses are reported for a suite of Karamay A-type granites from the Central Asian Orogenic Belt (CAOB) in the western Junggar region of northern Xinjiang, Northwest China, with the aim of investigating the sources and petrogenesis of A-type granites. The Karamay pluton includes monzogranite and syenogranite. Laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) zircon U-Pb dating yielded a concordant weighted mean 206Pb/238U age of 304 ± 5 Ma (n = 11), defining a late Carboniferous magmatic event. Geochemically, the rock suite is characterized by high SiO2, FeOt/MgO, total alkalies (K2O + Na2O), Zr, Nb, Y, Ta, Ga/Al, and rare earth elements (REEs) (except for Eu), and low contents of MgO, CaO, and P2O5, with negative Ba, Sr, P, Eu, and Ti anomalies. These features indicate an A-type affinity for the Karamay granitic intrusions. Isotopically, they display consistently depleted Sr-Nd isotopic compositions (initial 87Sr/86Sr = 0.7014-0.7022, εNd(t) = +5.6-+7.0). Geochronological, geochemical, and isotopic data suggest that the Karamay A-type granites were derived from remelting juvenile lower crust, followed by fractional crystallization. The Karamay A-type granites as well as widespread late Carboniferous magmatism in the western Junggar region of the southwestern CAOB may have been related to ridge subduction and a resultant slab window. This further demonstrates the importance of the late Palaeozoic granitic magmatism in terms of vertical crustal growth in northern Xinjiang. © 2014 © 2014 Taylor & Francis.