-
摘要:
珠江口盆地神狐海域是天然气水合物钻探和试验开采的重点区域，大量钻探取心、测井与地震等综合分析表明不同站位水合物的饱和度、厚度与气源条件存在差异。本文利用天然气水合物调查及深水油气勘探所采集的测井和地震资料建立地质模型，利用PetroMod软件模拟地层的温度场、有机质成熟度、烃源岩生烃量、流体运移路径以及不同烃源岩影响下的水合物饱和度，结果表明：生物成因气分布在海底以下1 500 m范围内的有机质未成熟地层，而热成因气分布在深度超过2 300 m的成熟、过成熟地层。水合物稳定带内生烃量难以形成水合物，形成水合物气源主要来自于稳定带下方向上运移的生物与热成因气。模拟结果与测井结果对比分析表明，稳定带下部生物成因气能形成的水合物饱和度约为10%，在峡谷脊部的局部区域饱和度较高；相对高饱和度（＞40%）水合物形成与文昌组、恩平组的热成因气沿断裂、气烟囱等流体运移通道幕式释放密切相关，W19井形成较高饱和度水合物的甲烷气体中热成因气占比达80%，W17井热成因气占比为73%，而SH2井主要以生物成因为主，因此，不同站位甲烷气体来源占比不同。
Abstract:The Shenhu area is located in the Pearl River Mouth Basin. It is a critical testing area for gas hydrate drilling and pilot production. Comprehensive studies of core samples and logging and seismic data suggest that gas hydrate saturation, thickness of gas hydrate layer and gas source conditions are different from sites to sites. Based on the geological model established by integrating the well log and seismic data from both gas hydrate and deep-water oil and gas drilling sites, we simulated the temperature field, organic matter maturity, hydrocarbon generation of source rocks, fluid migration pathways and gas hydrate saturation related to different source rocks with the PetroMod software. The results suggest that biogenic gas is mainly distributed in the immature organic strata 1 500 m below the seafloor, while thermogenic gas is distributed in the matured and over matured deposits over a depth of 2 300 m. Gas hydrate cannot be formed by in-situ biogenic gas within the gas hydrate stability zone. Therefore, the gases, which may form gas hydrate are mainly the biogenic and thermogenic gases moving up from the deep strata. The comparison between the modeling results and the log-derived saturation data suggest that the simulated saturation is around 10% for biogenic gas to become gas hydrate in the lower part of stability zone, while the value is higher at some areas such as canyon ridges. Higher saturation (＞40%) for hydrate formation is closely related to deep source thermogenic gas from the Wenchang and Enping Formations released in an episodic manner along the fluid migration channels such as sand layers, faults and gas chimneys. In addition, the methane contents from biogenic and thermogenic gases are calculated based on the modeling gas hydrate saturation. It shows that the thermogenic gas content is about 80% at Site W19 and 73% at Site W17, and nearly no thermogenic gas is found at Site SH2.
-
Key words:
- numerical modeling /
- thermogenic gas /
- fluid migration /
- gas hydrate saturation /
- Shenhu area
-
-
表 1 模型中各地层岩性、TOC和HI等参数
Table 1. The parameters of lithology, TOC and HI of each stratum for the numerical modeling
地层 沉积相 岩性 TOC/% HI/ （mg/g TOC） 第四纪万山组 浅海相 20%泥岩、80%粉砂岩 1 [5] 150 半深海相 30%泥岩、70%粉砂岩 0.5 [5] 150 粤海组韩江组 半深海相 30%泥岩、70%粉砂岩 0.5 150 珠江组 半深海相 30%泥岩、70%粉砂岩 0.5 [39] 150[39] 珠海组 浅湖相 60%泥岩、40%粉砂岩 0.75[39] 180[39] 三角洲相 100%砂岩 边滩相 50%泥岩、50%砂岩 恩平组 深湖相 100%泥岩 1[23,39-40] 200[23,39-40] 辫状三角洲相 75%泥岩、25%粉砂岩 文昌组 深湖相 75%泥岩、25%粉砂岩 2[23, 39-40] 450[23, 39-40] 辫状三角洲相 
下载: 导出CSV
-
[1] 朱俊章, 施和生, 庞雄, 等. 白云凹陷天然气生成与大中型气田形成关系[J]. 天然气地球科学, 2012, 23(2):213-221
ZHU Junzhang, SHI Hesheng, PANG Xiong, et al. Discussion on natural gas generation and giant-medium size gas field formation in Baiyun sag [J]. Natural Gas Geosciences, 2012, 23(2): 213-221.
[2] 何家雄, 卢振权, 张伟, 等. 南海北部珠江口盆地深水区天然气水合物成因类型及成矿成藏模式[J]. 现代地质, 2015, 29(5):1024-1034 doi: 10.3969/j.issn.1000-8527.2015.05.005
HE Jiaxiong, LU Zhenquan, ZHANG Wei, et al. Biogenetic and sub-biogenetic gas resource and genetic types of natural gas hydrates in Pearl River Mouth Basin, northern area of South China Sea [J]. Geoscience, 2015, 29(5): 1024-1034. doi: 10.3969/j.issn.1000-8527.2015.05.005
[3] 杨胜雄, 梁金强, 陆敬安, 等. 南海北部神狐海域天然气水合物成藏特征及主控因素新认识[J]. 地学前缘, 2017, 24(4):1-14
YANG Shengxiong, LIANG Jinqiang, LU Jing’an, et al. New understandings on the characteristics and controlling factors of gas hydrate reservoirs in the Shenhu area on the northern slope of the South China Sea [J]. Earth Science Frontiers, 2017, 24(4): 1-14.
[4] Li J F, Ye J L, Qin X W, et al. The first offshore natural gas hydrate production test in South China Sea [J]. China Geology, 2018, 1: 5-16.
[5] Wang X J, Collett T S, Lee M W, et al. Geological controls on the occurrence of gas hydrate from core, downhole log, and seismic data in the Shenhu area, South China Sea [J]. Marine Geology, 2014, 357: 272-292. doi: 10.1016/j.margeo.2014.09.040
[6] Wu N Y, Zhang H Q, Yang S X, et al. Gas hydrate system of Shenhu area, Northern South China Sea: Geochemical results [J]. Journal of Geological Research, 2011, 2011: 370298.
[7] Yu X H, Wang J Z, Liang J Q, et al. Depositional characteristics and accumulation model of gas hydrates in northern South China Sea [J]. Marine and Petroleum Geology, 2014, 56: 74-86. doi: 10.1016/j.marpetgeo.2014.03.011
[8] Zhang W, Liang J Q, Wei J G, et al. Geological and geophysical features of and controls on occurrence and accumulation of gas hydrates in the first offshore gas-hydrate production test region in the Shenhu area, Northern South China Sea [J]. Marine and Petroleum Geology, 2020, 114: 104191. doi: 10.1016/j.marpetgeo.2019.104191
[9] Kvenvolden K A. A review of the geochemistry of methane in natural gas hydrate [J]. Organic Geochemistry, 1995, 23(11-12): 997-1008. doi: 10.1016/0146-6380(96)00002-2
[10] Qian J, Wang X J, Collett T S, et al. Downhole log evidence for the coexistence of structure II gas hydrate and free gas below the bottom simulating reflector in the South China Sea [J]. Marine and Petroleum Geology, 2018, 98: 662-674. doi: 10.1016/j.marpetgeo.2018.09.024
[11] Yang S X, Liang J Q, Lei Y, et al. GMGS4 gas hydrate drilling expedition in the South China Sea [J]. Fire in the Ice, 2017, 17(1): 7-11.
[12] 于兴河, 梁金强, 方竞男. 珠江口盆地深水区晚中新世以来构造沉降与似海底反射(BSR)分布的关系[J]. 古地理学报, 2012, 14(6):787-800 doi: 10.7605/gdlxb.2012.06.010
YU Xinghe, LIANG Jinqiang, FANG Jingnan, et al. Tectonic subsidence characteristics and its relationship to BSR distribution in deep water area of Pearl River Mouth Basin since the Late Miocene [J]. Journal of Palaeogeography, 2012, 14(6): 787-800. doi: 10.7605/gdlxb.2012.06.010
[13] Jin J P, Wang X J, Guo Y Q, et al. Geological controls on the occurrence of recently formed highly concentrated gas hydrate accumulations in the Shenhu area, South China Sea [J]. Marine and Petroleum Geology, 2020, 116: 104294. doi: 10.1016/j.marpetgeo.2020.104294
[14] Wei J G, Fang Y X, Lu H L, et al. Distribution and characteristics of natural gas hydrates in the Shenhu Sea Area, South China Sea [J]. Marine and Petroleum Geology, 2018, 98: 622-628. doi: 10.1016/j.marpetgeo.2018.07.028
[15] 吴能友, 杨胜雄, 王宏斌, 等. 南海北部陆坡神狐海域天然气水合物成藏的流体运移体系[J]. 地球物理学报, 2009, 52(6):1641-1650 doi: 10.3969/j.issn.0001-5733.2009.06.027
WU Nengyou, YANG Shengxiong, WANG Hongbin, et al. Gas-bearing fluid influx sub-system for gas hydrate geological system in Shenhu area, Northern South China Sea [J]. Chinese Journal of Geophysics, 2009, 52(6): 1641-1650. doi: 10.3969/j.issn.0001-5733.2009.06.027
[16] Piñero E, Hensen C, Haeckel M, et al. 3-D numerical modelling of methane hydrate accumulations using PetroMod [J]. Marine and Petroleum Geology, 2016, 71: 288-295. doi: 10.1016/j.marpetgeo.2015.12.019
[17] Burwicz E, Reichel T, Wallmann K, et al. 3-D basin-scale reconstruction of natural gas hydrate system of the Green Canyon, Gulf of Mexico [J]. Geochemistry, Geophysics, Geosystems, 2017, 18(5): 1959-1985. doi: 10.1002/2017GC006876
[18] Kroeger K F, Plaza-Faverola A, Barnes P M, et al. Thermal evolution of the New Zealand Hikurangi subduction margin: Impact on natural gas generation and methane hydrate formation - A model study [J]. Marine and Petroleum Geology, 2015, 63: 97-114. doi: 10.1016/j.marpetgeo.2015.01.020
[19] 何丽娟, 雷兴林, 张毅. 南海北部神狐海域天然气水合物形成聚集的数值模拟研究[J]. 地球物理学报, 2011, 54(5):1285-1292 doi: 10.3969/j.issn.0001-5733.2011.05.017
HE Lijuan, LEI Xinglin, ZHANG Yi. Numerical modeling of gas hydrate accumulation in the marine sediments of Shenhu area, northern South China Sea [J]. Chinese Journal of Geophysics, 2011, 54(5): 1285-1292. doi: 10.3969/j.issn.0001-5733.2011.05.017
[20] Su P B, Liang J Q, Peng J, et al. Petroleum systems modeling on gas hydrate of the first experimental exploitation region in the Shenhu area, northern South China sea [J]. Journal of Asian Earth Sciences, 2018, 168: 57-76. doi: 10.1016/j.jseaes.2018.08.001
[21] Zhu H X, Xu T F, Zhu Z Y, et al. Numerical modeling of methane hydrate accumulation with mixed sources in marine sediments: Case study of Shenhu Area, South China Sea [J]. Marine Geology, 2020, 423: 106142. doi: 10.1016/j.margeo.2020.106142
[22] 庞雄, 施和生, 朱明, 等. 再论白云深水区油气勘探前景[J]. 中国海上油气, 2014, 26(3):23-29
PANG Xiong, SHI Hesheng, ZHU Ming, et al. A further discussion on the hydrocarbon exploration potential in Baiyun deep water area [J]. China Offshore Oil and Gas, 2014, 26(3): 23-29.
[23] Ping H W, Chen H H, Zhu J Z, et al. Origin, source, mixing, and thermal maturity of natural gases in the Panyu lower uplift and the Baiyun depression, Pearl River Mouth Basin, northern South China Sea [J]. AAPG Bulletin, 2018, 102(11): 2171-2200. doi: 10.1306/04121817160
[24] 谢志远, 杨建民, 孙龙涛, 等. 南海北缘白云凹陷北坡裂后断裂活动特征及构造沉积响应[J]. 热带海洋学报, 2017, 36(5):59-71
XIE Zhiyuan, YANG Jianmin, SUN Longtao, et al. The characteristics of post-rift fault activities and sedimentary response on the northern slope of the Baiyun sag in the northern margin of the South China Sea [J]. Journal of Tropical Oceanography, 2017, 36(5): 59-71.
[25] 米立军, 何敏, 翟普强, 等. 珠江口盆地深水区白云凹陷高热流背景油气类型与成藏时期综合分析[J]. 中国海上油气, 2019, 31(1):1-12
MI Lijun, HE Min, ZHAI Puqiang, et al. Integrated study on hydrocarbon types and accumulation periods of Baiyun sag, deep water area of Pearl River Mouth basin under the high heat flow background [J]. China Offshore Oil and Gas, 2019, 31(1): 1-12.
[26] 何家雄, 夏斌, 张启明, 等. 南海北部边缘盆地生物气和亚生物气资源潜力与勘探前景分析[J]. 天然气地球科学, 2005, 16(2):167-174 doi: 10.3969/j.issn.1672-1926.2005.02.007
HE Jiaxiong, XIA Bin, ZHANG Qiming, et al. Resources base and exploration potential of biogenic and sub-biogenic gas in marginal basin of the northern South China Sea [J]. Natural Gas Geoscience, 2005, 16(2): 167-174. doi: 10.3969/j.issn.1672-1926.2005.02.007
[27] Yang S X, Zhang M, Liang J Q, et al. Preliminary results of China's third gas hydrate drilling expedition: a critical step from discovery to development in the South China Sea [J]. Fire in the Ice, 2015, 15: 1-5.
[28] Zhang H Q, Yang S X, Wu N Y, et al. Successful and surprising results for China's first gas hydrate drilling expedition [J]. Fire in the Ice, 2007, 7(3): 6-9.
[29] 刘杰, 苏明, 乔少华, 等. 珠江口盆地白云凹陷陆坡限制型海底峡谷群成因机制探讨[J]. 沉积学报, 2016, 34(5):940-950
LIU Jie, SU Ming, QIAO Shaohua, et al. Forming mechanism of the slope-confined submarine canyons in the Baiyun sag, Pearl River Mouth Basin [J]. Acta Sedimentologica Sinica, 2016, 34(5): 940-950.
[30] 李华, 王英民, 徐强, 等. 南海北部珠江口盆地重力流与等深流交互作用沉积特征、过程及沉积模式[J]. 地质学报, 2014, 88(6):1120-1129
LI Hua, WANG Yingmin, XU Qiang, et al. Interactions between down-slope and along-slope processes on the northern slope of South China Sea: products, processes, and depositional model [J]. Acta Geologica Sinica, 2014, 88(6): 1120-1129.
[31] 付超, 于兴河, 梁金强, 等. 南海北部神狐海域不同类型水道及其天然气水合物成藏的差异[J]. 海洋地质与第四纪地质, 2017, 37(6):168-177
FU Chao, YU Xinghe, LIANG Jinqiang, et al. Types of sea-bottom channels and related gas hydrate accululations in the Shenhu area, South China Sea (SCS) [J]. Marine Geology and Quaternary Geology, 2017, 37(6): 168-177.
[32] 姜衡, 苏明, 雷新华, 等. 神狐海域海底峡谷群脊部细粒浊积体分布范围及意义[J]. 海洋地质与第四纪地质, 2018, 38(5):52-62
JIANG Heng, SU Ming, LEI Xinhua, et al. Distribution of fine-grained turbidites on canyon ridges in the Shenhu area of northern South China Sea and its implications [J]. Marine Geology and Quaternary Geology, 2018, 38(5): 52-62.
[33] 李杰, 何敏, 颜承志, 等. 南海北部荔湾3区块天然气水合物分布特征及目标识别[J]. 海洋科学, 2019, 43(5):81-89
LI Jie, HE Min, YAN Chengzhi, et al. The distribution and characteristics of gas hydrate in the Liwan3, northern slope of the South China Sea [J]. Marine Sciences, 2019, 43(5): 81-89.
[34] Kong L T, Chen H H, Ping H W, et al. Formation pressure modeling in the Baiyun Sag, northern South China Sea: Implications for petroleum exploration in deep-water areas [J]. Marine and Petroleum Geology, 2018, 97: 154-168. doi: 10.1016/j.marpetgeo.2018.07.004
[35] 柳保军, 庞雄, 王家豪, 等. 珠江口盆地深水区伸展陆缘地壳减薄背景下的沉积体系响应过程及油气勘探意义[J]. 石油学报, 2019, 40(S1):124-138 doi: 10.7623/syxb2019S1011
LIU Baojun, PANG Xiong, WANG Jiahao, et al. Sedimentary system response process and hydrocarbon exploration significance of crust thinning zone at extensional continental margin of deep-water area in Pearl River Mouth Basin [J]. Acta Petrolei Sinica, 2019, 40(S1): 124-138. doi: 10.7623/syxb2019S1011
[36] Carman P C. Flow of Gases through Porous Media[M]. New York: Academic Press Inc., 1956.
[37] McKenzie D. Some remarks on the development of sedimentary basins [J]. Earth and Planetary Science Letters, 1978, 40(1): 25-32. doi: 10.1016/0012-821X(78)90071-7
[38] 胡圣标, 龙祖烈, 朱俊章, 等. 珠江口盆地地温场特征及构造-热演化[J]. 石油学报, 2019, 40(S1):178-187 doi: 10.7623/syxb2019S1015
HU Shengbiao, LONG Zulie, ZHU Junzhang, et al. Characteristics of geothermal field and the tectonic-thermal evolution in Pearl River Mouth Basin [J]. Acta Petrolei Sinica, 2019, 40(S1): 178-187. doi: 10.7623/syxb2019S1015
[39] 朱俊章, 施和生, 庞雄, 等. 白云深水区东部油气成因来源与成藏特征[J]. 中国石油勘探, 2012, 17(4):20-28 doi: 10.3969/j.issn.1672-7703.2012.04.004
ZHU Junzhang, SHI Hesheng, PANG Xiong, et al. Origins and accumulation characteristics of hydrocarbons in eastern Baiyun deepwater area [J]. China Petroleum Exploration, 2012, 17(4): 20-28. doi: 10.3969/j.issn.1672-7703.2012.04.004
[40] 张功成, 杨海长, 陈莹, 等. 白云凹陷——珠江口盆地深水区一个巨大的富生气凹陷[J]. 地质勘探, 2014, 34(11):11-25
ZHANG Gongcheng, YANG Haichang, CHEN Ying, et al. The Baiyun sag: A giant rich gas-generation sag in the deepwater area of the Pearl River Mouth Basin [J]. Natural Gas Industry, 2014, 34(11): 11-25.
[41] Burnham A K. A simple kinetic model of petroleum formation and cracking[R]. California, U.S.: Lawrence Livermore National Laboratory, 1989.
[42] Sweeney J J, Burnham A K. Evaluation of a simple model of vitrinite reflectance based on chemical kinetics [J]. AAPG Bulletin, 1990, 74(10): 1559-1570.
[43] Wang X J, Hutchinson D R, Wu S G, et al. Elevated gas hydrate saturation within silt and silty clay sediments in the Shenhu area, South China Sea [J]. Journal of Geophysical Research, 2011, 116: B05102.
[44] Liu C L, Meng Q G, Hu G W, et al. Characterization of hydrate-bearing sediments recovered from the Shenhu area of the South China sea [J]. Interpretation, 2017, 5(3): SM13-SM23. doi: 10.1190/INT-2016-0211.1
-
图(8)
表(1)
计量
- 文章访问数: 2755
- PDF下载数: 136
- 施引文献: 0