THE LATE CRETACEOUS OSTRACOD FOSSILS OF THE JUNGGAR BASIN
1
Citation
0
Reference
20
Related Paper
Citation Trend
Abstract:
This study focuses on the lithostratigraphy and paleoenvironment reconstruction of the Upper Cretaceous in the Junggar Basin, which is characterized by a succession of red beds. The Upper Cretaceous in the Junggar Basin is regionally variable in thickness and poor in fossils. However, ostracod fossils from these rocks are characteristic of Late Cretaceous. Three ostracod assemblage zones have been recognized. These assemblage zones offer a biostratigraphic tool to correlation of Upper Cretaceous successions in the Junggar Basin.Keywords:
Ostracod
Lithostratigraphy
Red beds
Assemblage (archaeology)
Stratigraphic unit
Cite
Cite
Citations (78)
Abstract The marine Cretaceous of China is distributed mainly in southwestern Xinjiang, the West Kunlun Mountains, the Karakorum Mountains and most parts of Xizang (Tibet), with findings even from Taiwan. The marine Cretaceous of China may be divided into three sedimentary belts according to the lithologic and tectonic characters, biological provinces and the different modes of deposition. On the basis of recent research on the Cretaceous marine strata and faunas in China, the lithostratigraphic and biostratigraphic sequences have been preliminarily established and the division and correlation of strata and boundaries between the Jurassic and Cretaceous, Lower Cretaceous and Upper Cretaceous, as well as Cretaceous and Tertiary outlined; the position of the beach line of the Laurasian landmass in China and the events of the tectonic movement and the transgression and regression during the Cretaceous period are discussed.
Marine transgression
Lithology
Cite
Citations (0)
Based on discussing each unit of the lithostratigraphic rock composition,fossil assemblages and depositional environment from Mesozoic to Cenozoic in Wulaga fault-depression,Jiayin County,Heilongjiang Province,and comparison with other basins in Sunwu-Jiayin and Songliao basin,the authors divided the Mesozoic and Cenozoic strata into three tectonic layers and five lithostratigraphic units,and discussed their distribution and evolution,and made the regional geological map.The Wulaga basin shows three significantly different basin evolution stages,during which the two distinct unconformities are recognised,namely: the unconformity between upper Cretaceous and Lower Cretaceous and between the Upper Cretaceous and Neogene,thus made three different types of basin evolution stages in Wulaga from Mesozoic to Cenozoic;they are Early Cretaceous rift basin evolution stage,the Late Cretaceous large scale inland depression,and Neogene inland basin evolution stages.
Neogene
Paleogene
Cite
Citations (0)
Magnetostratigraphy
Paleogene
Chronology
Cite
Citations (7)
Paleoclimatology
Sequence (biology)
Sequence Stratigraphy
Vertebrate paleontology
Taphonomy
Cite
Citations (1)
According to fossil, sedimentation, microelement, featured mineral and clay mineral characteristics, an approach is conducted to the sedimentary environments including Late Carboniferous of northeastern margin, Early, Middle and Late Permian of northwestern and southern margins and eastern part of Junggar basin. It is suggested that the sedimentary environments of Fengcheng formation of Early Permain in northwestern margin, Lucaogou formation of Middle Permian in southern margin and Member-3 and Member-4 of Pingdiquan formation of Middle Permian in northeastern margin of Junggar basin could be bordtrland coastal lacustrine ones.
Margin (machine learning)
Sedimentation
Cite
Citations (25)
Conglomerate
Aptian
Cite
Citations (16)
Because upper Cretaceous of information is less,it is controversial that is existence.Recent years,we find again late Cretaceous charophyte fossil assemblage at Yuqi eare of north oilfield borehole(YQ1),which is first found at south of oilfield(S50).Through researching charophyte fossil assemblage,the earthquakes in contrasting,established stratigraphic sequence of Cretaceous.It is important significance that Mesozoic and Cenozoic boundary is deposition evolutionary and exploratory oil and gas in Tahe oilfield.
Assemblage (archaeology)
Tarim basin
Cite
Citations (0)
Section (typography)
Assemblage (archaeology)
Cite
Citations (1)
The Ziniquanzi Formation is distributed on the southern margin of the Junggar Basin with rare fossil remains. In literatures, only few Palcogene ostracodes and charophytes were recorded from the upper part of this formation. Therefore, according to stratigraphyical succession, the Ziniquanzi Formation was assigned to the Paleocene to the lower part of the Upper Eocene (《The Regional Stratigraphic Scale of Xinjiang Uygur Autonomous Region, Northwest China》 and 《The Lithostratigraphy of Xinjiang Uygur Autonomous Region》). Since 1992, significant fossil ostracodes and charophytes have, however, been found by the authors from the Ziniquanzi Formation in both outcrops and well sections. Based on the known geological extension of these fossils in the world, the age of the Ziniquanzi Formation should be Late Cretaceous to Middle Eocene. Biostratigraphical study shows also that the Ziniquanzi Formation is poorly developed in the outcrop area, as compared with that of the covered area. Certain layers while developed in the covered area are missing in the cropped sections. It is held that the rising and dropping of lake level and river equilibrium profile resulting from the change of climate control the development of strata on the southern margin of the Basin.
Lithostratigraphy
Outcrop
Diachronous
Cite
Citations (1)