Quantitative Characterization of Hydrate Occurrence Mode in Marine Pore-filling Gas Hydrate Reservoirs: Constraints from Acoustic and Resistivity Log Data

doi:10.19657/j.geoscience.1000-8527.2022.066

Abstract

Abstract:

In marine pore-filling natural gas hydrate reservoirs, hydrates are mainly produced in four occurrence modes: contact-cemented, grain-coated, matrix-supported, pore-suspended. Discrepancies in reservoir elastic-electrical properties are caused by different hydrate occurrence modes, and integrated acoustic and resistivity log data processing can effectively identify the hydrate occurrence mode. We used petrophysical models to simulate the reservoir acoustic and electrical responses, based on common log data (incl. resistivity and longitudinal velocity), and identified hydrate occurrence modes and calculated hydrate saturation. We also quantitatively characterized the occurrence modes, via calculating the relative proportion of the four hydrate occurrence modes. Actual drilling data from three typical marine hydrate reservoirs (i.e., Shenhu area of the South China Sea, Blake Ridge in North America, Hikurangi margin in New Zealand) were used as examples to quantify the hydrate reservoir occurrence mode: (1) In the hydrate reservoir at Shenhu Site SH2, hydrates are predominantly matrix-supported, accounting for ~64% of the total; (2) In the reservoir at Blake Ridge Site 994C, the hydrates are mainly of contact-cemented (27%) and grain-coated (51%) modes; (3) In the hydrate reservoir at Hikurangi Site U1518B, the hydrates are mainly of grain-coated (32%) and matrix-supported (47%) modes. Previous experimental studies on hydrate formation and occurrence mode show that the hydrates are more likely to be stored as contact-cemented, grain-coated and matrix-supported mode, which supports the analytical reliability. The integrated acoustic and electrical log data processing here enables the quantitative evaluation of hydrate reservoir occurrence mode in marine pore-filling gas hydrate reservoirs.

Key words: natural gas hydrate, occurrence mode, logging evaluation, saturation

CLC Number:

P631.8

WANG Shengyi, ZOU Changchun, PENG Cheng, WANG Hongcai, LU Jingan, KANG Dongju, WU Caowei, LAN Xixi, XIE Yingfeng. Quantitative Characterization of Hydrate Occurrence Mode in Marine Pore-filling Gas Hydrate Reservoirs: Constraints from Acoustic and Resistivity Log Data[J]. Geoscience, 2023, 37(01): 127-137.

Figures/Tables 10

Fig.1 Four typical occurrence models in marine pore-filling hydrate reservoirs and microscopic distributions

Fig.2 Petrophysics template between P-wave velocity and hydrate saturation

Table 1 Mineral fraction and content of hydrate reservoirs[45??-48]

区域	石英含量/%	黏土含量/%	方解石含量/%	长石含量/%
中国南海神狐海域	60	25	15	-
北美Blake海台	18	75	7	-
新西兰Hikurangi边缘	25	45	17	13

Table 2 Calculation results of hydrate occurrence model in hydrate reservoirs

区域	站位	储层范围/mbsf	电阻率/ (Ω·m)	纵波速度 /(m/s)	饱和度/%		赋存模式相对含量/%
区域	站位	储层范围/mbsf	电阻率/ (Ω·m)	纵波速度 /(m/s)	平均值	最大值	①	②	③	④
神狐海域	SH2	192~224	1.4~3.3	1770~2480	27.6	48.3	2	15	64	19
Blake海台	994C	212~429	0.6~1.2	1580~1980	8.4	21.1	27	51	6	16
Hikurangi边缘	U1518B	33~317	1.4~4.9	1710~2300	18.7	37.2	9	32	47	12

Fig.3 Resistivity logging data (a) and hydrate saturation from resistivity calculation and chlorine ion concentration analysis (b) for site SH2 in Shenhu area

Fig.4 Well-log data from site SH2 in Shenhu area and saturation for each hydrate occurrence model

Fig.5 Resistivity logging data (a) and hydrate saturation from resistivity calculation and chlorine ion concentration analysis (b) for site 994C in Blake ridge

Fig.6 Well-log data from site 994C in Blake ridge and saturation for each hydrate occurrence model (5-point smoothing results)

Fig.7 Resistivity logging data (a) and hydrate saturation from resistivity calculation and chlorine ion concentration analysis (b) for site U1518B in Hikurange margin

Fig.8 Well-log data from site U1518B in Hikurange margin and saturation for each hydrate occurrence model (3-point smoothing results)

References 48

[1]	LEE M W, COLLETT T S. In-situ gas hydrate hydrate saturation estimated from various well logs at the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope[J]. Marine and Petroleum Geology, 2011, 28(2): 439-449. DOI URL
[2]	GHOSH R, SAIN K, OJHA M. Effective medium modeling of gas hydrate-filled fractures using the sonic log in the Krishna-Godavari basin, offshore eastern India[J]. Journal of Geophysical Research(Solid Earth), 2010, 115(6): 3659-3667.
[3]	HU G, YE Y, ZHANG J, et al. Acoustic response of gas hydrate formation in sediments from South China Sea[J]. Marine and Petroleum Geology, 2014, 52: 1-8. DOI URL
[4]	LEI L, SEOL Y, CHOI J H, et al. Pore habit of methane hydrate and its evolution in sediment matrix-Laboratory visualization with phase-contrast micro-CT[J]. Marine and Petroleum Geology, 2019, 104: 451-467. DOI URL
[5]	胡高伟, 业渝光, 张剑, 等. 松散沉积物中天然气水合物生成、分解过程与声学特性的实验研究[J]. 现代地质, 2008, 22(3): 465-474.
[6]	刘洋, 陈强, 邹长春, 等. 气体水合物生成实验过程动态监测:一种新的ERT方法及其效果分析[J]. 现代地质, 2022, 36(1): 193-201.
[7]	PRIEST J A, BEST A I, CLAYTON C R I. Attenuation of seismic waves in methane gas hydrate-bearing sand[J]. Geophysical Journal International, 2005, 164(1): 149-159. DOI URL
[8]	李承峰, 胡高伟, 张巍, 等. 有孔虫对南海神狐海域细粒沉积层中天然气水合物形成及赋存特征的影响[J]. 中国科学(地球科学), 2016, 46(9): 1223-1230.
[9]	LV J, XUE K, ZHANG Z, et al. Pore-scale investigation of hydrate morphology evolution and seepage characteristics in hydrate bearing microfluidic chip[J]. Journal of Natural Gas Science and Engineering, 2021, 88: 103881. DOI URL
[10]	DVORKIN J, NUR A. Elasticity of high-porosity sandstones: theory for two North Sea data sets[J]. Geophysics, 1996, 61(5): 1363-1370. DOI URL
[11]	CHAND S, MINSHULL T A, GEI D, et al. Elastic velocity models for gas-hydrate-bearing sediments:a comparison[J]. Geophysical Journal International, 2004, 159(2): 573-590. DOI URL
[12]	ECKER C, DVORKIN J, NUR A. Sediments with gas hydrates: Internal structure from seismic AVO[J]. Geophysics, 1998, 63(5): 1659-1669. DOI URL
[13]	HELGERUD M B, DVORKIN J, NUR A, et al. Elastic-wave velocity in marine sediments with gas hydrates: effective medium modeling[J]. Geophysical Research Letters, 1999, 26(13): 2021-2024. DOI URL
[14]	宁伏龙, 梁金强, 吴能友, 等. 中国天然气水合物赋存特征[J]. 天然气工业, 2020, 40(8): 1-24,203.
[15]	ECKER C, DVORKIN J, NUR A M. Estimating the amount of gas hydrate and free gas from marine seismic data[J]. Geophysics, 2000, 65(2): 565-573. DOI URL
[16]	TALEB F, GARZIGLIA S, SULTAN N. Hydromechanical pro-perties of gas hydrate-bearing fine sediments from in situ testing[J]. Journal of Geophysical Research(Solid Earth), 2018, 123(11): 9615-9634.
[17]	王秀娟. 南海北部陆坡天然气水合物储层特征研究[D]. 青岛: 中国科学院研究生院(海洋研究所), 2006.
[18]	LEE M W, HUTCHINSON D R, COLLETT T S, et al. Seismic velocities for hydrate-bearing sediments using weighted equation[J]. Journal of Geophysical Research, 1996, 101(9): 20347-20358. DOI URL
[19]	COLLETT T S, LADD J. Detection of gas hydrate with downhole logs and assessment of gas hydrate concentrations (saturations) and gas volumes on the Blake Ridge with electrical resistivity log data[M]// Proceedings of the Ocean Drilling Program,Scientific Results. College Station: Ocean Drilling Program, 2000: 179-191.
[20]	SIMANDOUX P. Dielectric measurements of porous media:Application to the measurement of water saturations, study of the behavior of argillaceous formations[J]. Revue de L, Institut Franais du Petrole, 1963, 18(S1): 193-215.
[21]	TIMUR A. Velocity of compressional waves in porous media at permafrost temperatures[J]. Geophysics, 1968, 33(4): 584. DOI URL
[22]	CARCIONE J M, TINIVELLA U. Bottom-simulating reflectors: Seismic velocities and AVO effects[J]. Geophysics, 2000, 65(1): 54-67. DOI URL
[23]	LEE M W. Elastic velocities of partially gas-saturated unconsolidated sediments[J]. Marine and Petroleum Geology, 2004, 21(6): 641-650. DOI URL
[24]	ZIMMERMAN R W, KING M S. Effect of the extent of freezing on seismic velocities in unconsolidated permafrost[J]. Geophy-sics, 1986, 51(6): 1285-1290.
[25]	TERRY D A, KNAPP C C. A unified effective medium model for gas hydrates in sediments[J]. Geophysics, 2018, 83(6): 317-332. DOI
[26]	NGUYEN SYAB T, TANGC A M, TOD Q D, et al. A model to predict the elastic properties of gas hydrate-bearing sediments[J]. Journal of Applied Geophysics, 2019, 169: 154-164. DOI URL
[27]	PAN H, LI H, CHEN J, et al. A unified contact cementation theory for gas hydrate morphology detection and saturation estimation from elastic-wave velocities.[J]. Marine & PetroleumGeology, 2020, 113: 104146.
[28]	DVORKIN J, NUR A, YIN H. Effective properties of cemented granular materials[J]. Mechanics of Materials, 1994, 18(4): 351-366. DOI URL
[29]	GASSMANN F. Elastic waves through a packing of spheres[J]. Geophysics, 1951, 16(4): 673. DOI URL
[30]	BERRYMAN J G. Bounds and estimates for transport coefficients of random and porous media with high contrasts[J]. Journal of Applied Physics, 2005, 97(6): 063504. DOI URL
[31]	田海涛, 刘乐乐, 夏宇轩, 等. 水合物赋存形式对石英砂电性特征影响的数值模拟研究[J]. 地球物理学报, 2022, 65(4): 1439-1450.
[32]	ZHANG H, YANG S, WU N. Successful and surprising results for China’s first gas hydrate drilling expedition[J]. Fire in the Ice, 2007, 7(3): 6-9.
[33]	YANG S, ZHANG M, LIANG J. 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(2): 1-5.
[34]	YANG S, LIANG J, LEI Y. GMGS4 gas hydrate drilling expedition in the South China Sea[J]. Fire in the Ice, 2017, 17(1): 7-11.
[35]	王秀娟, 吴时国, 刘学伟, 等. 基于电阻率测井的天然气水合物饱和度估算及估算精度分析[J]. 现代地质, 2010, 24(5): 993-999.
[36]	梁劲, 王明君, 王宏斌, 等. 南海神狐海域天然气水合物声波测井速度与饱和度关系分析[J]. 现代地质, 2009, 23(2): 217-223.
[37]	梁劲, 王明君, 陆敬安, 等. 南海神狐海域含水合物地层测井响应特征[J]. 现代地质, 2010, 24(3): 506-514.
[38]	姚伯初, 杨木壮, 吴时国, 等. 中国海域的天然气水合物资源[J]. 现代地质, 2008, 22(3): 333-341.
[39]	陈芳, 苏新, 陆红锋, 等. 南海神狐海域有孔虫与高饱和度水合物的储存关系[J]. 地球科学, 2013, 38(5): 907-915.
[40]	龚跃华, 杨胜雄, 王宏斌, 等. 南海北部神狐海域天然气水合物成藏特征[J]. 现代地质, 2009, 23(2): 210-216.
[41]	张英, 郭依群, 莫午零, 等. 南海北部水合物中天然气成因及形成条件[J]. 现代地质, 2013, 27(5): 1180-1185.
[42]	陈芳, 周洋, 苏新, 等. 南海神狐海域含水合物层粒度变化及与水合物饱和度的关系[J]. 海洋地质与第四纪地质, 2011, 31(5): 95-100.
[43]	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.
[44]	苏丕波, 梁金强, 张伟, 等. 南海北部神狐海域天然气水合物成藏系统[J]. 天然气工业, 2020, 40(8): 77-89.
[45]	陈芳, 苏新, 周洋, 等. 南海北部陆坡神狐海域晚中新世以来沉积物中生物组分变化及意义[J]. 海洋地质与第四纪地质, 2009, 29(2): 1-8.
[46]	PAULL C K, MATSUMOTO R, WALLACE P J. Proceedings of the Ocean Drilling Program, 164 initial reports[R]. College Station: Ocean Drilling Program, 1996.
[47]	PECHER I A, BARNES P M, LEVAY L J. Proceedings of the Ocean Drilling Program, 372A initial reports[R]. College Station: International Ocean Discovery Program, 2019.
[48]	WALLACE L M, SAFFER D M, BARNES P M. Proceedings of the Ocean Drilling Program, 372B/375 initial reports[R]. College Station: International Ocean Discovery Program, 2019.