Coal-bearing source rocks formed in the transitional stage from faulting to depression nearshore China——A case from the Pinghu Formation in the Xihu Sag
-
摘要:
西湖凹陷是东海陆架盆地最重要的含油气凹陷，古近系晚始新统平湖组烃源岩是西湖凹陷主力烃源岩，晚始新世平湖组沉积时期西湖凹陷处于断―坳转换时期，平湖组为一套海陆过渡相煤系地层，形成于半封闭海湾沉积环境。本文对断坳转换平湖组煤系烃源岩的分布、母质来源和生烃特征进行系统分析。结果表明：断—坳转换下的煤系烃源岩广覆式分布，平湖组煤系烃源岩富含反映干燥针叶类裸子植物来源的异海松烷和潮湿蕨类植物来源的β-扁植烷等二萜类化合物，从斜坡带向凹陷中央具有β-扁植烷增加的特征。从显微结构上表现为富含树脂体的煤系烃源岩，其具有“早期利于生油、晚期持续生气”的生烃模式。正是这种分布格局、母质来源和生烃特征决定了西湖凹陷油气藏具有“东气西油”的分布格局。
Abstract:The Xihu Sag is the most important oil-bearing sag in the East China Sea Continental Shelf Basin, in which prevailed the Late Eocene source rocks of the Pinghu Formation, which was formed while the sag was situated in a transitional stage from faulting to depression. The Pinghu Formation is a set of marine-continental transitional coal-bearing sequence deposited in a semi-enclosed depositional environment of a bay. The authors systematically studied the distribution pattern, source of parent material and hydrocarbon generation characteristics of the coal-bearing source rocks. The results show that the coal-series source rocks were distributed widely in the sag and formed in a faulting-depression transitional stage. They are rich in iso-seasones and wet fern-derived β-bentane, reflecting a source from dried coniferous gymnosperms, in which diterpenoids are characterized by an increase in β-flatane from the slope zone to the center of the depression. From the microstructure, it is a kind of resin-rich coal-based source rock, which generated oil in early stage but gas in late-stage. The distribution pattern of “Gas in the East and Oil in the West” in the Xihu Sag is also determined by the distribution pattern, parent material source and hydrocarbon generation characteristics of the source rocks.
-
Key words:
- source rock /
- resinite /
- diterpanes /
- the Xihu Sag
-
-
表 1 西湖凹陷烃源岩丰度统计表
Table 1. Organic matter abundance in source rocks of Pinghu Formation in Xihu Sag
岩性 层段 TOC/% （S1+S2）/（mg/g） HI/（mgHC/gTOC） 氯仿沥青A/% HC/10−6 泥岩 一、二段 0.5～9.7
1.68（336）0.22～27.0
3.97（336）31.4～656.3
222.5（311）0.0033～0.624
0.108（44）157.6～5 884
633.84（43）三、四段 0.5～9.8
1.96（389）0.21～44.4
4.69（387）21.7～840.2
193.2（383）0.0142～0.619
0.16（26）110.7～2 834
866.73（21）五段 0.5～6.59
1.26（98）0.34～9.79
2.45（98）30.8～453.3
11.7（98）0.0276～0.5074
0.127（4）351.1～1 298.2
432.7（3）煤 一、二段 13.99～72.9
46.01（36）18.3～219.2
123.16（36）114～868.9
260.7（22）0.2261～3.3928
1.53（18）755.4～10 677.1
474.2（15）三、四段 20.8～57.5
38.95（21）51.4～215.8
123.6（21）192.9～403.3
261.8（17）1.81～1.93
1.87（2）8 203～10 998
9 600.5（2）五段 12.65～61.9
41.72（5）37.3～193.8
91.43（5）92.3～326.0
226.3（5）0.313（1） 1 447.62（1） 注： 
下载: 导出CSV
表 2 不同构造带平湖组泥岩丰度统计表
Table 2. Organic matter abundance in mudstones of Pinghu Formation from different tectonic units in Xihu Sag
构造带 TOC/% （S1+S2）/（mg/g） HI/（mgHC/gTOC） 氯仿沥青A/% HC/10−6 杭州斜坡带 0.51～3.9
1.4（39）0.28～14.9
2.75（39）51.6～382.8
155.9（35）0.003 3～0.687
0.032（12）126.3～2 400
672.2（5）平湖斜坡带 0.5～9.84
1.79（593）0.22～44.4
4.32（590）21.9～840.2
199.1（587）0.034 5～0.624
0.168（47）110.7～5 884
771.9（47）天台斜坡带 0.59～9.18
2.02（20）0.21～12.6
1.72（20）21.65～130.5
67.6（20）— — 黄岩构造带 0.52～3.3
1.38（109）0.51～12.3
4.39（109）63.4～656.3
334（88）0.028 3～0.288 6
0.082（15）167～1 653
474.2（15）天台构造带 0.51～8.37
2.34（62）0.3～16.5
3.44（62）44.9～191.3
112.1（62）— — 注： 
下载: 导出CSV
表 3 不同构造带平湖组煤丰度统计表
Table 3. Organic matter abundance in coals of Pinghu Formation from different tectonic units in Xihu Sag
构造带 TOC/% （S1+S2）/（mg/g） HI/（mgHC/gTOC） 氯仿沥青A/% 平湖斜坡带 20.8～61.9
41.01（29）51.36～215.75
122.55（29）92.27～403.32
255.52（24）0.248～1.93
1.35（4）天台斜坡带 53.29（1） 159.7（1） 277（1） 黄岩构造带 12.65～72.95
42.76（26）18.29～219.15
115.32（26）114～869
278.1（13）0.226 1～3.392 8
1.542（17）天台构造带 42.4～67.8
54.78（6）104.49～164.56
129.22（6）180.3～239.5
215.3（6）注： 
下载: 导出CSV
表 4 平湖组煤显微组分统计表
Table 4. Distribution of maceral composition in coals in the members of Pinghu Formation
组段 C1/% C2/% V/% I/% Al/% Cu/% Sp/% Re/% E/% 样品数 一段 5.0～21.6
13.53.0～84.4
48.377.5～93.5
86.50～7.7
2.80～1.9
0.80～3.3
1.30～6.6
1.62.6～9.9
6.86.2～16.5
10.76 二段 2.8～30.8
14.514.2～78
57.873.1～92
85.90～24.6
1.70～2.5
0.80.2～5.6
2.10.2～5.4
2.41.2～14
6.62.3～20.3
12.423 三段 0～40.9
15.612.8～95.8
53.977.7～99.6
870～14
1.40～8.8
0.40～13.8
2.10～8.8
2.10～19.7
5.90.4～21.7
11.634 四段 1.6～57.6
15.014.7～87.9
58.873.9～98.4
88.80～6.8
1.30～7.7
0.70～8.9
1.90～9.7
2.10～17.3
3.80.8～23.2
9.848 五段 1.7～21.2
9.937.2～80.9
63.374.6～97.7
87.20～8.5
2.10～15.1
1.90.3 ～5.4
20～4.7
1.30～17.7
4.51.5～23
10.619 注：C1为均质镜质体；C2为基质镜质体；V为镜质组；I为惰质组；Al为藻类体；Cu为角质体；Sp为孢子体；Re为树脂体；E为壳质组；各有机显微组分总和为100%。
下载: 导出CSV
表 5 不同构造带煤显微组分统计表
Table 5. Maceral composition of coals from different tectonic units
构造带 C1/% C2/% V/% I/% Al/% Cu/% Sp/% Re/% E/% 数量（件） 杭州斜坡带 0.5～82.4
18.62.5～83.6
61.079.4～90.9
86.40～3.1
0.70～0.9
0.20.4～4.3
1.50.3～9.1
3.30～11
7.18.7～19.2
13.014 平湖斜坡带 0～57.6
14.63～95.8
54.464.3～99.6
87.10～14
1.70～15.1
0.90～13.8
2.10～9.7
2.10～19.7
4.90.4～33.1
11.1115 黄岩构造带 0.7～38.9
1635.2～84.4
63.973.1～93.5
87.60～24.6
1.40～11
1.20～6.6
1.60～5.4
1.20.4～13.8
6.62.3～16.6
10.943 嘉兴构造带 5.5～36.8
15.335.1～86.3
70.786～95.5
910～3.2
0.80～2.
70.90～1
0.40～2.2
1.12.6～10.9
5.83.8～13.7
8.28 天台构造带 0～67
22.69.9～98.3
63.177.6～98.7
90.90～6.4
2.00～6.1
1.30～6.3
1.00～0.3
0.10～15.1
3.21.3～16.4
7.19 注：中央反转构造带北部的为花港组煤样
下载: 导出CSV
-
[1] 刘道燕. 东海陆架盆地烃源岩及其烃类特点[M]∥姜亮. 东海陆架盆地油气资源勘探论文集. 北京: 石油工业出版社, 2004: 181-187.
LIU Daoyan. Characteristics of Source Rocks and Their Hydrocarbns in East China Sea Continental Shelf Basin[M]∥JIANG Liang. Proceedings of Petroleum Resources Exploration in East China Sea Shelf Basin. Beijing: Petroleum Industry Press, 2004: 181-187.
[2] 蒋一鸣, 周倩羽, 李帅, 等. 西湖凹陷西部斜坡带平湖组含煤岩系沉积环境再思[J]. 中国煤炭地质, 2016, 28(8):18-25 doi: 10.3969/j.issn.1674-1803.2016.08.04
JIANG Yiming, ZHOU Qianyu, LI Shuai, et al. Reconsideration of Pinghu Formation coal-bearing rock series sedimentary environment in western slope of Xihu Depression [J]. Coal Geology of China, 2016, 28(8): 18-25. doi: 10.3969/j.issn.1674-1803.2016.08.04
[3] 熊斌辉, 王春红, 张锦伟, 等. 西湖凹陷古近系平湖组煤层分布及油气意义[J]. 海洋石油, 2007, 27(3):27-33, 40 doi: 10.3969/j.issn.1008-2336.2007.03.004
XIONG Binhui, WANG Chunhong, ZHANG Jinwei, et al. The distribution and exploration implications of coal beds of Pinghu Formation, Paleologene in Xihu Sag [J]. Offshore Oil, 2007, 27(3): 27-33, 40. doi: 10.3969/j.issn.1008-2336.2007.03.004
[4] 周倩羽, 沈文超, 张信, 等. 西湖凹陷古近系平湖组聚煤环境特征及模式[J]. 河北工程大学学报: 自然科学版, 2016, 33(1):105-107, 112
ZHOU Qianyu, SHEN Wenchao, ZHANG Xin, et al. The coal-accumulating environments characteristics and coal-forming pattern of Pinghu Formation(Paleogene) in Xihu Depression [J]. Journal of Hebei University of Engineering: Natural Science Edition, 2016, 33(1): 105-107, 112.
[5] 李贤庆, 钟宁宁, 王铁冠, 等. 东海西湖凹陷早第三纪烃源岩生烃组分剖析[J]. 煤田地质与勘探, 1995, 23(6):24-31
LI Xianqing, ZHONG Ningning, WANG Tieguan, et al. The study on hydrocarbon-generating macerals of Lower Tertiary source rocks in Xihu Sag, East China Sea Basin [J]. Coal Geology & Exploration, 1995, 23(6): 24-31.
[6] 傅宁. 东海盆地西湖凹陷煤系烃源岩及凝析油中的二萜化合物[J]. 中国海上油气(地质), 1994, 8(1):21-28
FU Ning. Diterpenoid compounds in coal measures and condensates in Xihu Sag of East China Sea Basin [J]. China Offshore Oil and Gas (Geology), 1994, 8(1): 21-28.
[7] 朱杨明, 周洁, 顾圣啸, 等. 西湖凹陷始新统平湖组煤系烃源岩分子地球化学特征[J]. 石油学报, 2012, 33(1):32-39 doi: 10.7623/syxb201201004
ZHU Yangming, ZHOU Jie, GU Shengxiao, et al. Molecular geochemistry of Eocene Pinghu Formation coal-bearing source rocks in the Xihu Depression, East China Sea Shelf Basin [J]. Acta Petrolei Sinica, 2012, 33(1): 32-39. doi: 10.7623/syxb201201004
[8] 陈斯忠, 宋建民, 陈伟煌. 对海上找气的思考[J]. 中国海上油气(地质), 2003, 17(3):153-159
CHEN Sizhong, SONG Jianmin, CHEN Weihuang. Pondering upon offshore gas exploration in China [J]. China Offshore Oil and Gas (Geology), 2003, 17(3): 153-159.
[9] 周心怀, 蒋一鸣, 唐贤君. 西湖凹陷成盆背景、原型盆地演化及勘探启示[J]. 中国海上油气, 2019, 31(3):1-10
ZHOU Xinhuai JIANG Yiming, TANG Xianjun. Tectonic setting, prototype basin evolution and exploration enlightenment Of Xihu Sag in East China Sea Basin [J]. China Offshore Oil and Gas, 2019, 31(3): 1-10.
[10] 叶加仁, 顾惠荣, 贾健谊. 东海西湖凹陷油气地质条件及其勘探潜力[J]. 海洋地质与第四纪地质, 2008, 28(4):111-116
YE Jiaren, GU Huirong, JIA Jianyi. Petroleum geological condition and exploration potential of Xihu Depression, East China Sea [J]. Marine Geology & Quaternary Geology, 2008, 28(4): 111-116.
[11] 张建培, 徐发, 钟韬, 等. 东海陆架盆地西湖凹陷平湖组-花港组层序地层模式及沉积演化[J]. 海洋地质与第四纪地质, 2012, 32(1):35-41
ZHANG Jianpei, XU Fa, ZHONG Tao, et al. Sequence stratigraphic models and sedimentary evolution of Pinghu and Huagang Formations in Xihu Trough [J]. Marine Geology & Quaternary Geology, 2012, 32(1): 35-41.
[12] 杨传胜, 杨长清, 李刚, 等. 东海陆架盆地中—新生界油气勘探研究进展与前景分析[J]. 海洋地质与第四纪地质, 2018, 38(2):136-147
YANG Chuansheng, YANG Changqing, LI Gang, et al. Prospecting of Meso-cenozoic hydrocarbon in the East China Sea Shelf Basin [J]. Marine Geology & Quaternary Geology, 2018, 38(2): 136-147.
[13] 蔡佳, 祁鹏, 宋双. 东海盆地西湖凹陷花港组下段沉积相分析[J]. 海洋地质与第四纪地质, 2017, 37(2):56-65
CAI Jia, QI Peng, SONG Shuang. Sedimentary facies of the lower Huagang Formation in Xihu Depression of Donghai Basin [J]. Marine Geology & Quaternary Geology, 2017, 37(2): 56-65.
[14] 周心怀, 高顺莉, 高伟中, 等. 东海陆架盆地西湖凹陷平北斜坡带海陆过渡型岩性油气藏形成与分布预测[J]. 中国石油勘探, 2019, 24(2):153-164
ZHOU Xinhuai, GAO Shunli, GAO Weizhong, et al. Formation and distribution of marine-continental transitional lithologic reservoirs in Pingbei slope belt, Xihu Sag, East China Sea Shelf Basin [J]. China Petroleum Exploration, 2019, 24(2): 153-164.
[15] 秦兰芝, 徐志星, 刁慧, 等. 西湖凹陷烃源岩地震反演评价与预测[J]. 中国石油和化工标准与质量, 2017, 37(16):66-67, 69 doi: 10.3969/j.issn.1673-4076.2017.16.032
QIN Lanzhi, XU Zhixing, DIAO Hui, et al. Seismic inversion evaluation and prediction of source rocks in Xihu Sag [J]. China Petroleum and Chemical Standard and Quality, 2017, 37(16): 66-67, 69. doi: 10.3969/j.issn.1673-4076.2017.16.032
[16] 王铁冠, 钟宁宁, 侯读杰, 等. 低熟油气形成机理与分布[M]. 北京: 石油工业出版社, 1995: 175-181.
WANG Tieguan, ZHONG Ningning, HOU Dujie, et al. Immature Oils Forming Mechanism and Distribution[M]. Beijing: Petroleum Industry Press, 1995: 175-181.
[17] 钱门辉, 侯读杰, 蒋启贵, 等. 西湖凹陷煤系烃源岩显微组分组成特征及地质意义[J]. 石油实验地质, 2012, 34(2):182-185 doi: 10.3969/j.issn.1001-6112.2012.02.014
QIAN Menhui, HOU Dujie, JIANG Qigui, et al. Features and geologic significance of maceral composition of coal-bearing source rocks in Xihu Sag [J]. Petroleum Geology & Experiment, 2012, 34(2): 182-185. doi: 10.3969/j.issn.1001-6112.2012.02.014
[18] 王铁冠, 钟宁宁, 候读杰, 等. 中国低熟油的几种成因机制[J]. 沉积学报, 1997, 15(2):75-83
WANG Tieguan, ZHONG Ningning, HOU Dujie, et al. Several genetic mechanisms of immature crude oils in China [J]. Acta Sedimentologica Sinica, 1997, 15(2): 75-83.
[19] 李贤庆, 钟宁宁, 王铁冠, 等. 东海盆地西湖凹陷下第三系烃源岩显微组分组成和成烃组分剖析[J]. 中国海上油气(地质), 1995, 9(1):19-25
LI Xianqing, ZHONG Ningning, WANG Tieguan, et al. The study on maceral composition and hydrocarbon-generating macerals of Lower Tertiary source rocks in Xihu Sag, East China Sea Basin [J]. China Offshore Oil and Gas (Geology), 1995, 9(1): 19-25.
[20] 李贤庆, 钟宁宁, 熊波, 等. 西湖凹陷煤系源岩的有机质热演化研究[J]. 中国煤田地质, 1997, 9(1):33-36
LI Xianqing, ZHONG Ningning, XIONG Bo, et al. A study on thermal evolution of organic matter in coal-bearing source rocks of Xihu Sag [J]. Coal Geology of China, 1997, 9(1): 33-36.
[21] 仝志刚, 贺清, 何仕斌, 等. 东海西湖凹陷地温场及其对烃源岩的作用[J]. 石油实验地质, 2009, 31(5):466-471, 484 doi: 10.3969/j.issn.1001-6112.2009.05.006
TONG Zhigang, HE Qing, HE Shibin, et al. Geothermal field and its effect on source rock in the Xihu Sag, the East China Sea Basin [J]. Petroleum Geology & Experiment, 2009, 31(5): 466-471, 484. doi: 10.3969/j.issn.1001-6112.2009.05.006
[22] 何将启.东海西湖凹陷构造—热历史分析[D].上海: 同济大学, 2004: 92.
HE Jiangqi. Tectono－thermal history of Xihu Depression, East China Sea[D]. Shanghai: Tongji University, 2004: 92.
[23] 刘景彦, 林畅松, 肖建新, 等. 东海西湖凹陷第三系主要不整合面的特征、剥蚀量的分布及其意义[J]. 现代地质, 1999, 13(4):432-438
LIU Jingyan, LIN Changsong, XIAO Jianxin, et al. Characteristics and erosions of the major Tertiary unconformities and their significance to petroleum exploration in the Xihu Trough, the East China Sea [J]. Geoscience, 1999, 13(4): 432-438.
[24] 周祖翼, 贾健谊, 李家彪, 等. 东海西湖凹陷反转构造定量研究: 来自裂变径迹分析数据的约束[J]. 海洋地质与第四纪地质, 2002, 22(1):63-67
ZHOU Zuyi, JIA Jianyi, LI Jiabiao, et al. Quantitative study on inversion structures in Xihu Depression, East China Sea: constraints from fission track analysis data [J]. Marine Geology & Quaternary Geology, 2002, 22(1): 63-67.
[25] 许婷, 侯读杰, 曹冰. 东海盆地西湖凹陷凝析油和轻质油生源母质剖析[J]. 地球化学, 2015, 44(3):289-300 doi: 10.3969/j.issn.0379-1726.2015.03.008
XU Ting, HOU Dujie, CAO Bing. Study of precursors for Condensates and light oils in Xihu Sag of East China Sea Basin [J]. Geochimica, 2015, 44(3): 289-300. doi: 10.3969/j.issn.0379-1726.2015.03.008
[26] 彼得斯 K E, 莫尔多万 J M. 生物标记化合物指南——古代沉积物和石油中分子化石的解释[M].北京: 石油工业出版社, 1995: 120-124.
Peters K E, Moldowan J M. The Biomarker Guide[M]. Beijing: Petroleum Industry Press, 1995: 120-124.
[27] 侯读杰, 张林晔. 实用油气地球化学图鉴[M]. 北京: 石油工业出版社, 2003: 146-148.
HOU Dujie, ZHANG Linye. Illustrated Handbook of Oil and Gas Geochemistry[M]. Beijing: Petroleum Industry Press, 2003: 146-148.
-
图(14)
表(5)
计量
- 文章访问数: 1895
- PDF下载数: 61
- 施引文献: 0