Depositional setting and evolution of the Paleogene—Neogene foreland basin of southern margin of Junggar Basin
Gao Zhiyong1, Han Guomeng2, Zhu Rukai1, Guo Hongli1, Wang Daochuan1, Li Benliang1
1 Petroleum Geology Research and Laboratory Center RIPED，Beijing 100083 2 Research Institute of Exploration and Development， Dagang Oilfield Company， PetroChina, Dagang 300280， Tianjin
Abstract：Good ways are found in studying clastic deposits of the Paleogene and Neogene in southern margin of Junggar Basin. The ways are ① Lithofacies and sedimentary facies are distinguished by outcrop analyses and core and thin section description, ② The boundaries of deposits are identified by recognition of shoreline evolution according to different characteristics of seismic facies and different locations of facies change and ③ The main and minor provenances are distinguished by characteristics of heavy mineral assemblages and isopach maps of sandstones. Characteristics of sedimentary facies have been studied by this comprehensive method. The depositional framework and evolution of the southern margin of Junggar Basin were analyzed on this basis. The results indicate that during the deposition of the Paleogene Ziniquanzi Formation， 4 large scale fan delta deposits were developed in thrust belt of the Tianshan Mountains and the lake level was lower. During the deposition of the Anjihaihe Formation， 3 fan delta deposits with decreasing sizes were developed in front of the Tianshan Mountains due to the lake level rising and the fan delta retrogration. Fan delta was not developed in Huoerguosi area. During the deposition of the Early Neogene Shawan Formation， fan deltas with larger scales were developed in front of the Mountains， the topography differences were large， the slope was steep and the climate was arid due to lake level quick falling. There are 2 main sedimentary provenances and 2 minor ones from the Paleogene to Neogene in southern margin of Junggar Basin. The main provenances are the Dongwan-Tugulu-Manas anticline in central area， the Xihu-Dushanzi anticline in western area. The minor sedimentary provenances are respectively the Hutubi anticline in eastern area and the Huoerguosi anticline in central western area. These four provenances are distributed in south-north direction. There is a very important provenance in Kayindike area which is from the foreland uplifting area.
Gao Zhiyong,Han Guomeng,Zhu Rukai et al. Depositional setting and evolution of the Paleogene—Neogene foreland basin of southern margin of Junggar Basin[J]. JOPC, 2009, 11(5): 491-502.
