珠江口盆地恩平21洼文昌组泥岩元素地球化学特征及其与有机质富集的关系

彭光荣; 石创; 龙祖烈; 吴静; 熊万林; 朱定伟; 马宁

doi:10.16028/j.1009-2722.2022.233

珠江口盆地恩平21洼文昌组泥岩元素地球化学特征及其与有机质富集的关系

1.
中海石油（中国）有限公司深圳分公司，深圳 518054

2.
中海石油深海开发有限公司，深圳 518054

基金项目: 中国海洋石油集团总公司“十四五”重大科技项目“陆缘裂谷盆地深层/超深层油气成藏条件与成藏机制研究−珠江口盆地珠一坳陷”（KJGG2022-0403）

详细信息

作者简介: 彭光荣（1978—），男，硕士，高级工程师，主要从事油气地质与油气勘探综合研究工作. E-mail：penggr@cnooc.com.cn

通讯作者: 石创（1988—），男，硕士，工程师，主要从事油气成藏和资源评价研究工作. E-mail：shichuang@cnooc.com.cn

中图分类号: P736; P744.4

收稿日期: 2022-08-26

刊出日期: 2023-06-28

Relationship between element geochemical characteristics and organic matter enrichment of Wenchang Formation mudstones in Enping Sub-sag 21, Pearl River Mouth Basin

1.
Shenzhen Branch of CNOOC (China) Ltd., Shenzhen 518054, China

2.
CNOOC Deepwater Development Ltd., Shenzhen 518054, China

More Information

Corresponding author: SHI Chuang, shichuang@cnooc.com.cn

Received Date: 26 August 2022

Publish Date: 28 June 2023

摘要

摘要:
泥岩的元素特征能够较好地保存于原始沉积记录。为了明确恩平21洼文昌组泥岩元素地球化学特征及其与有机质富集的关系，选择YJ-1井文昌组10个泥岩岩屑样品，开展有机碳、常量元素和微量元素测试。在分析常量、微量元素地球化学特征的基础上，利用元素地球化学方法，系统分析洼陷文昌期古气候、古水深、古氧相和古生产力等古环境指标。文昌组泥岩元素平均含量对UCC(Upper Continental Crust)做标准化处理，恩平21洼文昌组泥岩具有富集Al₂O₃、K₂O和MnO，贫CaO、MgO和Na₂O；富Li、Be、Zn、Rb、Cs、Ba、Pb、Th和U，贫Sr、V和Cr的特征。古环境指标显示恩平21洼文昌期气候属于温暖湿润-温热潮湿，湖泊水深相对较深，纵向水深变化小，水体分布稳定，水体以还原环境为主，古生产力相对较高，但纵向差异大。泥岩有机碳含量与古生产力参数相关性较差，而与水体还原性之间具有较好的正相关关系，表明有机质富集受控于水体的氧化还原程度，水体还原条件有利于有机质的保存，有机质富集属于“保存模式”。进一步分析显示，古气候条件是文昌组有机质富集的关键性因素，温热潮湿的气候对湖泊生产力有一定的积极影响，同时降水量较大，湖泊水体较深，有利于湖底还原环境的形成和保持，进而有利于有机质的保存。
- 有机质富集 /
- 沉积环境 /
- 元素地球化学 /
- 文昌组 /
- 恩平21洼 /
- 珠江口盆地
Abstract:
The elements of mudstones can well preserve the original sedimentary records. To define the element geochemical characteristics of the Wenchang Formation mudstones in Enping Subsag 21 and its relationship with enrichment of organic matter, 10 debris samples of the mudstones from well YJ-1 were collected, on which geochemical tests of organic carbon, major elements and trace elements were conducted. The geochemical characteristics of major and trace elements were examined, and paleo-environmental indicators such as paleo-climate, paleo-water depth, paleo-oxygenation facies, and paleo-productivity of the Wenchang Formation in the subsag were systematically analyzed. Compared with the content of major and trace elements in the Upper Continental Crust (UCC), major elements of the Wenchang Formation mudstones in Enping Subsag 21 are relatively enriched in Al₂O₃, K₂O, and MnO, and poor in CaO, MgO, and Na₂O. Trace elements are rich in Li, Be, Zn, Rb, CS, Ba, Pb, Th, U, and poor in Sr, V, and Cr. Paleoenvironmental indicators show that climate of Enping Subsag 21 in the Wenchang period was warm-moist to warm-humid. The paleo-lake was relatively deep and stable. Redox environment of the lake was mainly sub-reductive. Paleo-productivity of the lake was relatively high, and the vertical difference was significant. Correlation between organic carbon content of mudstones and paleo-productivity parameters is poor, but there is a good positive correlation with reducibility of the lake. Enrichment of organic matter was controlled by oxidation-reduction degree of the lake. Reduction condition of the lake was conducive to the preservation of organic matter. Enrichment of organic matter belongs to the "preservation mode". Further analysis shows that paleo-climate is the key factor for enrichment of organic matter in the Wenchang Formation. Warm and humid climate has a certain positive impact on productivity of the lake. Meanwhile, the precipitation was large, and the lake was deep, which was conducive to a reducing environment at the lake bottom, and thus conducive to the preservation of organic matter.
- organic matter enrichment /
- depositional environment /
- element geochemistry /
- Wenchang Formation /
- Enping Sub-sag 21 /
- Pearl River Mouth Basin

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图 1 珠江口盆地恩平21洼区域位置及地层划分

Figure 1.

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图 2 恩平21洼YJ-1井取样位置

Figure 2.

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图 3 标准化后恩平21洼文昌组常量元素和微量元素含量

Figure 3.

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图 4 恩平21洼YJ-1井文昌组泥岩古水深、古气候、古氧相和古生产力地球化学参数纵向变化

Figure 4.

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图 5 恩平21洼YJ-1井泥岩古氧相和古生产力与有机碳含量的关系

Figure 5.

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图 6 恩平21洼YJ-1井泥岩古水深同古氧相及古气候的关系

Figure 6.

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表 1 恩平21洼YJ-1井泥岩有机碳及常量元素测试结果

Table 1. Amount of organic carbon and major elements of mudstones samples of Well YJ-1 in Enping Sub-sag 21

%
样号	深度/m	TOC	Al₂O₃	CaO	Fe₂O₃	K₂O	MgO	MnO	Na₂O	P₂O₅	TiO₂	SiO₂
1	3 058	2.43	15.65	1.44	4.27	4.08	0.84	0.12	0.51	0.11	0.53	64.51
2	3 103	2.82	22.25	0.34	5.76	3.94	0.89	0.12	0.62	0.18	0.63	55.94
3	3 143	2.45	22.26	0.31	5.98	3.51	0.89	0.19	0.59	0.19	0.62	55.46
4	3 183	2.3	22.90	0.44	6.50	3.70	0.94	0.18	0.60	0.21	0.64	53.85
5	3 228	3.13	21.35	0.48	5.77	3.59	0.92	0.17	0.60	0.22	0.59	56.47
6	3 283	3.48	22.15	0.47	6.03	3.64	0.96	0.13	0.66	0.20	0.65	55.18
7	3 318	2.66	24.28	0.38	6.73	4.20	1.00	0.19	0.63	0.17	0.72	50.55
8	3 333	2.17	26.82	0.35	4.05	4.44	0.78	0.07	0.49	0.12	0.78	52.94
9	3 378	3.49	22.34	0.26	3.96	3.35	0.68	0.06	0.32	0.05	0.62	56.17
10	3 393	6.00	23.20	0.17	1.71	2.74	0.40	0.02	0.23	0.04	0.61	61.92
UCC	/	/	15.40	3.59	5.04	2.80	2.48	0.10	3.27	0.15	0.64	66.60
注：TOC为总有机碳含量，UCC为全球平均大陆上地壳成分，UCC数据据参考文献[13-15]。

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表 2 恩平21洼YJ-1井泥岩微量元素测试结果

Table 2. Amount of trace elements of mudstones samples of Well YJ-1 in Enping Sub-sag 21

样号		1	2	3	4	5	6	7	8	9	10	UCC
深度/m		3 058	3 103	3 143	3 183	3 228	3 283	3 318	3 333	3 378	3 393	/
微量元素含量/（μg/g）	Li	58.67	60.21	55	50.44	51.07	46	70.72	80.29	57.33	110.08	24
	Be	3.42	4.53	4.38	4.16	4.74	3.9	5.18	4.67	3.21	3.16	2.1
	Sc	9.52	11.64	11.6	11.41	11.91	10.82	13.23	11.59	9.58	7.53	14
	V	60.75	70.11	71.54	69.64	74.45	63.54	77.35	60.33	53.43	34.6	97
	Cr	33.28	31.14	31.6	29.53	32.76	30.29	37.67	30.63	25.85	7.79	92
	Co	7.4	8.88	9.2	8.88	9.34	8.09	10.34	9.01	9.24	3.92	17.3
	Ni	11.77	11.93	12.05	11.25	12.53	11.31	14.65	15.29	11.53	3.83	47
	Cu	11.45	15.5	16.83	16.17	17.45	14.67	17.56	14.09	13.17	5.88	28
	Zn	90.1	113.47	115.65	114.68	135.28	118.44	149.97	138.76	110.06	84.02	67
	Ga	15.48	19.76	19.15	18.81	20.52	17.68	22.6	22.96	18.08	18.44	17.5
	Rb	193.82	182.17	160.05	156.09	179.98	153.58	193.1	199.8	143.41	124.09	84
	Sr	118.11	102.85	92.31	90.3	108.01	83.08	108.09	103.49	64.06	55.29	320
	Y	24.36	30.4	26.99	27.68	31.16	27.86	35.66	33.47	32.3	22.14	21
	Zr	213.88	209.6	204.63	204.73	213.34	200.82	207.91	221.75	191.65	242.62	193
	Nb	13.78	15.77	15.12	14.55	16.6	14.85	18.73	22.73	17.05	17.57	12
	Mo	0.34	0.79	0.86	1.05	1.01	0.62	0.85	0.4	0.65	0.17	1.5
	Cs	16.5	13.6	12.48	11.6	13.35	11.26	13.64	13.55	14.22	14.02	4.9
	Ba	1737.42	1061.04	979.53	1159.48	2289.83	1323.55	1927.97	3047.43	1981.67	2257.21	628
	Hf	6.79	6.95	6.7	6.74	7.01	6.63	6.94	6.99	6.17	7.59	5.3
	Tl	0.92	1.02	0.97	0.94	1.03	0.91	1.13	1.03	1.02	0.66	0.9
	Pb	44.44	46	44.32	46.79	62.51	52.97	75.74	67.09	77.64	75.22	17
	Th	15.64	22.66	21.1	20.1	21.33	19.37	25.15	20.65	18.97	18.93	10.5
	U	5.15	8.4	8.02	7.52	7.71	7	8.2	5.82	5.32	4.55	2.7
注：UCC为全球平均大陆上地壳成分。

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参考文献(31)

[1]	宋春晖,鲁新川,邢强,等. 临夏盆地晚新生代沉积物元素特征与古气候变迁[J]. 沉积学报,2007,25(3):409-416. doi: 10.3969/j.issn.1000-0550.2007.03.012
[2]	程岳宏,于兴河,韩宝清,等. 东濮凹陷北部古近系沙三段地球化学特征及地质意义[J]. 中国地质,2010,37(2):357-366. doi: 10.3969/j.issn.1000-3657.2010.02.009
[3]	陈斌,李勇,邓涛,等. 晚三叠世龙门山前陆盆地须家河组泥页岩沉积环境及有机质富集模式[J]. 地质科学,2019,54(2):434-451. doi: 10.12017/dzkx.2019.028
[4]	石创,龙祖烈,朱俊章,等. 珠江口盆地白云凹陷恩平组泥岩元素地球化学特征及环境指示意义[J]. 海洋地质与第四纪地质,2020,40(5):79-86.
[5]	石创. 珠江口盆地阳江东凹文昌组泥岩稀土元素特征及其地质意义[J]. 地质科技通报,2022,41(3):1-11.
[6]	彭光荣,张向涛,许新明,等. 南海北部珠江口盆地阳江凹陷油气勘探重要发现与认识[J]. 中国石油勘探,2019,24(3):267-279. doi: 10.3969/j.issn.1672-7703.2019.03.001
[7]	田立新,张向涛,彭光荣,等. 珠江口盆地阳江凹陷石油地质特征及成藏主控因素[J]. 中国海上油气,2020,32(1):13-22.
[8]	刘军,彭光荣,朱定伟,等. 珠江口盆地阳江凹陷东部地区断控成藏条件[J]. 大地构造与成矿学,2021,45(1):123-130. doi: 10.16539/j.ddgzyckx.2021.01.010
[9]	吴静,张晓钊,白海军,等. 珠江口盆地阳江凹陷中新统潮控体系及其岩性圈闭勘探意义[J]. 地球科学,2021,46(10):3673-3689.
[10]	汪晓萌,彭光荣,吴静,等. 珠江口盆地恩平21洼文昌组沉积期原型盆地及其对优质烃源岩的控制[J]. 大地构造与成矿学,2021,45(1):158-167.
[11]	熊万林,龙祖烈,朱俊章,等. 阳江凹陷恩平21洼不同沉积环境烃源岩发育特征及成藏贡献[J]. 油气地质与采收率,2021,28(5):50-56.
[12]	刘欣颖,吴静,朱定伟,等. 珠江口盆地多期走滑构造与叠合型拉分盆地:以阳江东凹为例[J]. 大地构造与成矿学,2021,45(1):6-19. doi: 10.16539/j.ddgzyckx.2021.01.002
[13]	TAYLOR S R, MCLENNAN S M. The Continental Crust: Its Composition and Evolution[M]. Oxford: Blackwell, 1985: 312.
[14]	RUDNICK R L, SHAN S. Composition of the Continental Crust[M]//Treatise on Geochemistry: The Crust. Oxford: Elsevier-Pergamon, 2004: 1-64.
[15]	WEDEPOHL K H. Enviromental influences on the chemical composition of shales and clays[J]. Physics and Chemistry of the Earth,1971,8(71):305-333.
[16]	尹锦涛,俞雨溪,姜呈馥,等. 鄂尔多斯盆地张家滩页岩元素地球化学特征及与有机质富集的关系[J]. 煤炭学报,2017,42(6):1544-1556. doi: 10.13225/j.cnki.jccs.2016.1342
[17]	MAKEEN Y M,MOHAMMED H H,WAN G A. The origin type and preservation of organic of the Barremian-Aptian organic-rich shales in the Muglad Basin,Southern Sudan,and their relation to paleoenvironment and paleoclimate conditions[J]. Marine and Petroleum Geology,2015,65:187-197. doi: 10.1016/j.marpetgeo.2015.03.003
[18]	NESBITT H W,YOUNG G M. Early Proterozoic climate and plate motion inferred from major element chemistry of lutites[J]. Nature,1982,299:715-717. doi: 10.1038/299715a0
[19]	HARNOIS L. The CIW index:a new chemical index of weathering[J]. Sedimentary Geology,1988,55(3/4):319-322.
[20]	NESBITT H W,YOUNG G M. Prediction of some weathering trends of plutonic and volcanic rocks based on thermodynamic and kinetic considerations[J]. Geochim Cosmochim Acta,1984,48:1523-1534. doi: 10.1016/0016-7037(84)90408-3
[21]	MCLENNAN S M. Weathering and global denudation[J]. Journal of Geology,1993,101(2):295-303. doi: 10.1086/648222
[22]	冯连君,储雪蕾,张同钢,等. 莲沱砂岩—南华大冰期前气候转冷的沉积记录[J]. 岩石学报,2006,22(9):2387-2393. doi: 10.3321/j.issn:1000-0569.2006.09.015
[23]	郭艳琴,余芳,李洋,等. 鄂尔多斯盆地东部石盒子组盒8沉积环境的地球化学表征[J]. 地质科学,2016,51(3):872-890.
[24]	JONES B J,MANNING A C. Comparison of geochemical indices used for the interpretation palaeoredox conditions in ancient mudstone[J]. Chemical Geology,1994,111(1/4):111-129. doi: 10.1016/0009-2541(94)90085-X
[25]	王志勇,孟仟祥,王作栋,等. 吐哈盆地台北凹陷侏罗系煤系源岩地球化学分类及意义[J]. 沉积学报,2010,12(6):1238-1243.
[26]	张水昌,张宝民,边立曾,等. 中国海相烃源岩发育控制因素[J]. 地学前缘,2005,12(3):39-48.
[27]	罗情勇,钟宁宁,朱雷,等. 华北北部中元古界洪水庄组埋藏有机碳与古生产力的相关性[J]. 科学通报,2013,58(11):1036-1047.
[28]	DYMOND J,SUESS E,LYLE M. Barium in deep-sea sediment:a geochemical proxy for paleoproductivity[J]. Paleoceanography,1992,7:163-181. doi: 10.1029/92PA00181
[29]	TIMOTHY D A,CALVERT S E. Systematics of variations in excess Al and Al /Ti in sediment from the central equatorial Pacific[J]. Paleoceangraphy,1998,13(2):127-130.
[30]	任景玲,张经,刘素美. 以Al/Ti比值为地球化学示踪剂反演海洋古生产力的研究进展[J]. 地球科学进展,2005,20(12):1314-1320. doi: 10.3321/j.issn:1001-8166.2005.12.006
[31]	刘占红,李思田,辛仁臣,等. 地层记录中的古气候信息及其与烃源岩发育的相关性:以渤海黄河口凹陷古近系为例[J]. 地质通报,2007,26(7):830-840. doi: 10.3969/j.issn.1671-2552.2007.07.006