气候变化领域集成服务门户(CCPortal): Paleoproductivity of the Chang 7 unit in the Ordos Basin (North China) and its controlling factors

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DOI	10.1016/j.palaeo.2020.109741
	Paleoproductivity of the Chang 7 unit in the Ordos Basin (North China) and its controlling factors
	Chen G.; Gang W.; Chang X.; Wang N.; Zhang P.; Cao Q.; Xu J.
发表日期	2020
ISSN	0031-0182
卷号	551
英文摘要	Primary paleoproductivity provides basic organic matter for the formation of high-quality hydrocarbon source rock. A progressive method to quantitatively calculate paleoproductivity on the basis of total organic carbon (TOC) has been proposed to evaluate the contribution of primary paleoproductivity to a hydrocarbon source rock with high organic matter abundance. In this study, pyrite contents, organic maceral compositions and high-resolution sedimentation rates (SRs) were used to recover the amount of organic matter oxidation and to exclude the effect of terrestrial clastic input during the deposition of the Chang 7 sediment. Multiple calculation methods were used to quantitatively reconstruct paleoproductivity, and the results suggest that the Ordos Basin was a eutrophic lacustrine basin (approximately 2 × 104 mg C cm−2 kyr−1 to 10 × 104 mg C cm−2 kyr−1) during the Chang 7 stage compared with modern lake productivity. The paleoclimatic analysis indicates that a warm humid paleoclimate was beneficial for increasing the weathering intensity, which could have provided more nutrient inputs to the depositional environment with incoming terrestrial debris. In addition, the plate collision between the North China Block and Yangtze Block generated moderate volcanic ash that spread to the study area and provided large amounts of essential nutrients for algae blooms. Moreover, a brackish water condition promoted upward mixing of deep water, which inhibited water mass stratification and then facilitated primary paleoproductivity. In general, the Chang 7 high-quality hydrocarbon source rock is a result of increased paleoproductivity resulting from suitable paleoclimate conditions, brackish water masses and abundant essential nutrient inputs. © 2020 Elsevier B.V.
英文关键词	Depositional environment; Organic macerals; Paleoclimate; Sediment provenance
语种	英语
scopus关键词	brackish water; chemical composition; deep water; depositional environment; organic matter; paleoclimate; paleoproductivity; source rock; total organic carbon; volcanic ash; water mass; China; North China Block; Ordos Basin; Yangtze Platform; algae
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/150482
作者单位	College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China; College of Geosciences, China University of Petroleum, Beijing, 102249, China; No.2 Gas Production Plant of PetroChina Changqing Oilfield Company, Yulin, 719000, China; Exploration and Development Research Institute of Liaohe Oilfield Company, Panjin, 124000, China
推荐引用方式 GB/T 7714	Chen G.,Gang W.,Chang X.,et al. Paleoproductivity of the Chang 7 unit in the Ordos Basin (North China) and its controlling factors[J],2020,551.
APA	Chen G..,Gang W..,Chang X..,Wang N..,Zhang P..,...&Xu J..(2020).Paleoproductivity of the Chang 7 unit in the Ordos Basin (North China) and its controlling factors.Palaeogeography, Palaeoclimatology, Palaeoecology,551.
MLA	Chen G.,et al."Paleoproductivity of the Chang 7 unit in the Ordos Basin (North China) and its controlling factors".Palaeogeography, Palaeoclimatology, Palaeoecology 551(2020).