Abstract
Estimation of S-wave velocity using logging data has mainly been performed for sandstone, mudstone and oil and gas strata, while its application to hydrate reservoirs has been largely overlooked. In this paper we present petrophysical methods to estimate the S-wave velocity of hydrate reservoirs with the P-wave velocity and the density as constraints. The three models used in this paper are an equivalent model (MBGL), a three-phase model (TPBE), and a thermo-elasticity model (TEM). The MBGL model can effectively describe the internal relationship among the components of the rock, and the estimated P-wave velocities are in good agreement with the measured data (2.8% error). However, in the TPBE model, the solid, liquid and gas phases are considered to be independent of each other, and the estimation results are relatively low (46.6% error). The TEM model is based on the sensitivity of the gas hydrate to temperature and pressure, and the accuracy of the estimation results is also high (3.6% error). Before the estimation, the occurrence patterns of hydrates in the Shenhu area were examined, and occurrence state one (the hydrate is in solid form in the reservoir) was selected for analysis. By using the known P-wave velocity and density as constraints, a reasonable S-wave velocity value (ranging from 400 to 1100 m s−1 and for a hydrate layer of 1100 m s−1) can be obtained through multiple iterations. These methods and results provide new data and technical support for further research on hydrates and other geological features in the Shenhu area.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Castagna, J. P., Batzle, M. L., and Eastwood, R. L., 1985. Relationship between compressional wave and shearwave velocities in clastic silicate rock. Geophysics, 50 (4): 571–581.
Castagna, J. P., Batzle, M. L., and Kan, T. K., 1993. Rock physics–The link between rock properties and AVO response. In: Offset-Dependent Reflectivity–Theory and Practice of AVO Analysis, Investigations in Geophysics, Society of Exploration Geophysiscists. Tulsa, USA, 135–171.
Chen, F., Su, X., Zhou, Y., Lu, H, F., and Liu, G., 2009. Variations in biogenic components of late Miocene Holocene sediments from Shenhu area in the northern South China Sea and their geological implication. Marine Geology & Quaternary Geology, 29: 1–8.
Chen, F., Zhou, Y., Su, X., Liu, G., and Lu, G., 2011. Gas hydrate saturation and its relation with grain size of the hydrate-bearing sediments in the Shenhu area of northern South China Sea. Marine Geology & Quaternary Geology, 31 (5): 95–100.
Cheng, W, B., Wu, Y, R., Liang, C. W., Lin, J, Y., and Hsu, S. K., 2018. Imaging P-and S-wave velocity structures in hydrate bearing sediments along an OBS profile across the Yuan-An Ridge, off southwest Taiwan. Terrestrial Atmospheric & Oceanic Sciences, 29 (1): 39–50.
Dai, J., Xu, H, B., Snyder, F., and Dutta, N., 2004. Detection and estimation of gas hydrates using rock physics and seismic inversion: Examples from the northern deepwater Gulf of Mexico. The Leading Edge, 23 (1): 60–66.
Dong, N., Huo, Z. Z., Sun, Z. D., Liu, Z. S., and Sun, Y. Y., 2014. An investigation of a new rock physics model for shale. Journal of Geophysics, 57 (6): 1990–1998 (in Chinese with English abstract).
Ecker, C., Dvorkin, J., and Nur, A., 1998. Sediments within gas hydrates: Internal structure from seismic AVO. Geophysics, 63 (5): 1659–1669.
Fu, S. Y., and Lu, J. A., 2010. The characteristics and origin of gas hydrate in Shenhu area, South China Sea. Ocean Geology Dynamics, 26 (9): 6–10 (in Chinese with English abstract).
Krief, M., Garat, J., Stellingwerff, J., and Ventre, J., 1990. A petrophysical interpretation using the velocities of P and S waves (full-waveform sonic). The Log Analyst, 31: 355–369.
Lin, H. W., 2015. A method for S-wave velocity estimation based on rock physical analysis. Master thesis. Chengdu University of Technology.
Li, Q. Z., 1992. Characteristics of P-wave and S-wave velocity of rock. Petroleum Geophysical Prospecting, 27 (1): 1–12 (in Chinese with English abstract).
Ma, Y., Kong, L., Liang, Q. Y., Lin, J. Q., and Li, S. Z., 2014. Characteristics of hazardous geology factors on the Shenhu continental slope in the northern South China Sea. Earth Science–Journal of China University of Geosciences, 36 (9): 1364–1372 (in Chinese with English abstract).
Mavko, G., Mukerji, T., and Dvorkin, J., 2009. The Rock Physics Handbook: Tools for Seismic Analysis in Porous Media. Cambridge University Press, Cambridge, U. K., 1–503.
Mindlin, R. D., 1949. Compliance of elastic bodies in contact. Journal of Applied Mechanics, 16 (3): 259–268.
Milholland, P., Manghnani, M. H., Schlanger, S. O., and Sutton, G. H., 1980. Geoacoustic modeling of deep-sea carbonate sediments. Journal of the Acoustical Society of America, 68 (5): 1351–1360.
Nur, A., Mavko, G., Dvorkin, J., and Galmudi, D., 2000. Critical porosity: A key to relating physical properties to porosity on rocks. Leading Edge, 17 (1): 878–881.
Shuey, R. T., 1985. A simplification of the Zoeppritz equations. Geophysics, 50: 609–614.
Wang, X., Hutchinson, D. R., Wu, S., Yang, S., and Guo, Y., 2011. Elevated gas hydrate saturation within silt and silty clay sediments in the Shenhu area, South China Sea. Journal of Geophysical Research: Solid Earth, 116 (B5): 35–52.
Wang, X. J., Wu, S. G., and Liu, X. W., 2006. Factors affecting the estimation of gas hydrate and free gas saturation. Chinese Journal of Geophysics, 49 (2): 504–511 (in Chinese with English abstract).
Wu, N. Y., Yang, S, X., and Wang, H. B., 2009. Gas-bearing fluid influx sub-system for gas hydrate geological system in Shenhu area, northern South China Sea. Chinese Journal of Geophysics, 52 (6): 1641–1650.
Wu, N. Y., Zhang, H. Q., Yang, S. X., Liang, J. Q., and Wang, H. B., 2007. Preliminary discussion on natural gas hydrate (NGH) reservoir system Shenhu area, north slope of South China Sea. Natural Gas Industry, 57 (5): 1664–1674 (in Chinese with English abstract).
Wu, S. G., Xie, Y. B., Qin, Q., and Li, Q. P., 2014. Shallow drilling geological disasters of oil and gas in deepwater. Prospecting Engineering, 24 (9): 38–42 (in Chinese with English abstract).
Xing, L., Liu, X. Q., Zhang, J., Liu, H. S., Zhang, J., Li, Z. Z., and Wang, J. H., 2018. Sensitivity analysis of P-waves and S-waves to gas hydrate in the Shenhu area using OBS. Journal of Ocean University of China, 17 (1): 139–146.
Xu, S., and White, R. E., 1995. A new velocity model for sandclay mixtures. Geophysical Prospecting, 43 (1): 91–118.
Zhang, G. Z., Chen, H. Z., Wang, Q., and Yin, X. Y., 2013. Estimation of S-wave velocity and anisotropic parameters using fractured carbonate rock physics model. Journal of Geophysics, 56 (5): 1707–1715 (in Chinese with English abstract).
Zhang, X. G., Xu, H. N., Liu, X. W., Zhang, M., Wu, Z. L., Liang, J. Q., Wang, H. B., and Sha, Z. B., 2014. The acoustic velocity characteristics of sediment with gas hydrate revealed by integrated exploration of 3D seismic and OBS data in Shenhu area. Journal of Geophysics, 57 (4): 1169–1176.
Acknowledgements
The study is supported by the National Natural Science Foundation of China (Nos. 41304096 and 41176077), the National Science and Technology Major Project of China (No. 2016ZX05024-001-002), the National High-tech R&D Program of China (863 Program; No. 2013AA0925 01), and the Fundamental Research Funds for the Central Universities (No. 201762019).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Liu, X., Xing, L. & Liu, H. Estimation of S-wave Velocity for Gas Hydrate Reservoir in the Shenhu Area, North South China Sea. J. Ocean Univ. China 17, 1091–1102 (2018). https://doi.org/10.1007/s11802-018-3676-6
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11802-018-3676-6