Iodine-129 chronological study of brines from an Ordovician paleokarst reservoir in the Lunnan oilfield, Tarim Basin

doi:10.1016/j.apgeochem.2015.10.012

	Iodine-129 chronological study of brines from an Ordovician paleokarst reservoir in the Lunnan oilfield, Tarim Basin
	Ning, Chen 3,4; Hou Xiaolin 3,4; Zhang Baoshou 1; Xiao Zhongyao 1; Chen, Jian 2; Liu, Dayong 2; Peng, Ping'an 2
刊名	APPLIED GEOCHEMISTRY
	2016-02-01
卷号	65 期号:2016 页码:14-21
关键词	Iodine Iodine 129 Oilfield Water Tarim Basin
DOI	10.1016/j.apgeochem.2015.10.012
文献子类	Article
英文摘要	Previous studies have shown that brines in an Ordovician paleokarst reservoir of the Lunnan oilfield in the Tarim Basin, China, are the product of mixing of paleo-evaporated seawater in the east with paleo-meteoric waters in the west. In order to put time constraints on the brine and related hydrocarbons in this field, 10 brine samples were collected, for which the iodine concentrations and I-129/I ratios were measured and discussed. The iodine concentration (3.70-31.2 mg/L) and the I-129/I ratio (189 -897 x 10(-15)) show that the iodine in the paleoseawater and meteoric water (MW) had different origins and I-129 characteristics. The paleoseawater has a high iodine content (similar to 31 mg/L), indicating that iodine was introduced into the reservoir along with thermally generated hydrocarbons, possibly in the Cretaceous, from the Caohu Sag in the eastern area. Based on consideration of all possible origins of iodine and I-129 in the brines, it is suggested that the meteoric water maintained its initial iodine content (0.01 mg/L) and I-129/I ratio (1500 x 10(-15)), whereas the iodine-enriched paloseawater (IPSW) exhibited a secular I-129 equilibrium (N-sq = 39 atom/mu L) as a result of fissiogenic I-129 input in the reservoir over a long period of time. The model of brine evolution developed on that basis confirmed that meteoric water entered the reservoir in the Miocene at about 10 Ma, and partially mixed with the iodine-enriched paleoseawater. The movement of meteoric water was facilitated by faults created during the Himalayan orogeny, then became more dense after dissolving Paleogene halite and infiltrated into the reservoir at high pressure. The iodine and I-129 concentration in the brine contains information about the path and history of the fluid in the reservoir. This may be useful in oil exploration, since the movement of water was, to some extent, related to hydrocarbon migration. (C) 2015 Elsevier Ltd. All rights reserved.
WOS关键词	ACCELERATOR MASS-SPECTROMETRY ; RESIDENCE TIMES ; SOURCE AGES ; NW CHINA ; TAKLIMAKAN DESERT ; FORMATION WATERS ; CRUSTAL FLUIDS ; NATURAL I-129 ; PORE WATERS ; IN-SITU
WOS研究方向	Geochemistry & Geophysics
语种	英语
WOS记录号	WOS:000366648500002
内容类型	期刊论文
源URL	[http://ir.ieecas.cn/handle/361006/5864]
专题	地球环境研究所_加速器质谱中心
作者单位	1.PetroChina, Tarim Oilfield Co, Kuerle 841000, Peoples R China 2.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Organ Geochem, Guangzhou 510640, Guangdong, Peoples R China 3.Chinese Acad Sci, Xian AMS Ctr, Xian 710075, Peoples R China 4.Chinese Acad Sci, Inst Earth Environm, State Key Lab Loess & Quaternary Geol, Xian 710075, Peoples R China
推荐引用方式 GB/T 7714	Ning, Chen,Hou Xiaolin,Zhang Baoshou,et al. Iodine-129 chronological study of brines from an Ordovician paleokarst reservoir in the Lunnan oilfield, Tarim Basin[J]. APPLIED GEOCHEMISTRY,2016,65(2016):14-21.
APA	Ning, Chen.,Hou Xiaolin.,Zhang Baoshou.,Xiao Zhongyao.,Chen, Jian.,...&Peng, Ping'an.(2016).Iodine-129 chronological study of brines from an Ordovician paleokarst reservoir in the Lunnan oilfield, Tarim Basin.APPLIED GEOCHEMISTRY,65(2016),14-21.
MLA	Ning, Chen,et al."Iodine-129 chronological study of brines from an Ordovician paleokarst reservoir in the Lunnan oilfield, Tarim Basin".APPLIED GEOCHEMISTRY 65.2016(2016):14-21.