干旱区生态环境知识资源中心(Arid): Deposition conditions of the Jurassic lacustrine source rocks in the East Fukang Sag, Junggar Basin, NW China: Evidence from major and trace elements

Arid

DOI	10.1002/gj.3714
	Deposition conditions of the Jurassic lacustrine source rocks in the East Fukang Sag, Junggar Basin, NW China: Evidence from major and trace elements
	Qiao, Jinqi 1,2; Liu, Luofu 1,2; Shang, Xiaoqing 3
通讯作者	Liu, Luofu ; Shang, Xiaoqing
来源期刊	GEOLOGICAL JOURNAL
ISSN	0072-1050
EISSN	1099-1034
出版年	2020
卷号	55 期号:7 页码:4936-4953
英文摘要	The Fukang Sag hosts prolific Jurassic lacustrine source rocks, which include the Badaowan (J(1)b), Sangonghe (J(1)s), and Xishanyao (J(2)x) formations in the Junggar Basin. Depositional conditions were reconstructed based on various major and trace element proxies for the East Fukang Sag during the Jurassic. The palaeowater depth in the sag was shallow and did not display a great change during the deposition of the J(1)b, J(1)s, and J(2)x formations, as indicated by lithological composition and the widespread ripple cross-beddings. The oxic to dysoxic and fresh-water conditions were postulated to prevail in the sag during the deposition of these source rocks, as revealed by concentrations of salinity- and redox-sensitive trace elements [i.e., V/Cr, Ni/Co, (Cu+Mo)/Zn, Sr/Ba ratios, and Sr, Mn, Ga contents] derived from the source rocks. The seasonal salinity stratification superposed on preexisting thermal stratification led to the appearance of the chemocline in the J(1)b Formation. The palaeoclimate regime was humid and warm during the depositions of the J(1)b and the upper J(1)s formations, and warmer and drier during the deposition of the lower J(1)s Formation, but the palaeoclimate gradually became semi-arid and semi-cold during the deposition of the upper J(2)x Formation, as implied by various proxies (i.e., Sr/Cu ratio, C-value, and CIA value). Despite the fact that the oxic to dysoxic conditions were not conducive for organic matter (OM) preservation, the significantly moderate-high palaeoproductivity (suggested by, i.e., Ba content and Ba/Al ratio), which was promoted by a suitable supply of nutrient from terrestrial inputs in the shallow water was the controlling factorfor the OM accumulation on the margin of the sag, but the low OM concentration was controlled by the palaeoredox conditions in the central area, which was far from the OM input source [suggested by the relationship between total organic carbon content and stable carbon isotope composition of OM (delta C-13(org))]. The analyses based on Rock-Eval pyrolysis, maceral composition, C/N ratio of isolated kerogen, and delta C-13(org) value showing the OM was derived from terrestrial higher plants with C3 plants (type III kerogen) are consistent with the palaeoenvironmental analysis.
英文关键词	Geochemistry depositional environment Jurassic Fukang Sag Junggar Basin
类型	Article
语种	英语
国家	Peoples R China
收录类别	SCI-E
WOS记录号	WOS:000502942500001
WOS关键词	PERMIAN-TRIASSIC TRANSITION ; EOCENE JIJUNTUN FORMATION ; UYGUR AUTONOMOUS REGION ; MULTIPLE SOURCE ROCKS ; ORGANIC-MATTER INPUT ; RARE-EARTH-ELEMENTS ; CAINAN OIL-FIELD ; NORTHWEST CHINA ; MARINE-SEDIMENTS ; GEOCHEMICAL CHARACTERISTICS
WOS类目	Geosciences, Multidisciplinary
WOS研究方向	Geology
EI主题词	2019-12-17
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/311826
作者单位	1.China Univ Petr, State Key Lab Petr Resources & Prospecting, Beijing, Peoples R China; 2.China Univ Petr, Coll Geosci, Beijing, Peoples R China; 3.Xian Shiyou Univ, Sch Earth Sci & Engn, Xian, Shaanxi, Peoples R China
推荐引用方式 GB/T 7714	Qiao, Jinqi,Liu, Luofu,Shang, Xiaoqing. Deposition conditions of the Jurassic lacustrine source rocks in the East Fukang Sag, Junggar Basin, NW China: Evidence from major and trace elements[J],2020,55(7):4936-4953.
APA	Qiao, Jinqi,Liu, Luofu,&Shang, Xiaoqing.(2020).Deposition conditions of the Jurassic lacustrine source rocks in the East Fukang Sag, Junggar Basin, NW China: Evidence from major and trace elements.GEOLOGICAL JOURNAL,55(7),4936-4953.
MLA	Qiao, Jinqi,et al."Deposition conditions of the Jurassic lacustrine source rocks in the East Fukang Sag, Junggar Basin, NW China: Evidence from major and trace elements".GEOLOGICAL JOURNAL 55.7(2020):4936-4953.