检索结果-南通市图书馆

Characteristics of fluid substitution in porous rocks

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2009年第2期6卷 139-145页

作者： Li Shengjie School of Resource and Information Technology China University of Petroleum Beijing 102249 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Key Laboratory of CNPC Geophysical Exploration China University of Petroleum Beijing 102249 China

Analysis of the effect of changes in fluid properties of rocks on the compressional-wave velocity VP and shear-wave velocity Vs is very important for understanding the rock physical properties, especially in oilfield exploration and development. The fluid substitution process was analyzed by using ultrasonic measurement and theoretical calculations. The results showed that the effect of fluid substitution on the rock elastic modulus was mainly controlled by fluid properties, saturation, and confining pressure. For a rock with specific properties and porosity, the result of theoretical prediction for fluid substitution accorded with the experimental result under high confining pressure （higher than 60 MPa for our experimental data）, but failed to describe the trend of experimental result under low confining pressure and VP predicted by Gassmann＇s equation was higher than that measured by experiment. A higher porosity resulted in stronger sensitivity of the bulk modulus of saturated rocks to the change of fluid properties.

关键词： fluid substitution velocity bulk modulus porosity saturation

Gas reservoir identification by seismic AVO attributes on fluid substitution

在线全文

学校读者我要写书评

暂无评论

Applied Geophysics 2012年第2期9卷 139-148,233,234页

作者：李景叶油气资源与探测国家重点实验室中国北京102249 中国石油大学(北京)CNPC物探重点实验室中国北京102249

Traditionally, fluid substitutions are often conducted on log data for calculating reservoir elastic properties with different pore fluids. Their corresponding seismic responses are computed by seismic forward modeling for direct gas reservoir identification. The workflow provides us with the information about reservoir and seismic but just at the well. For real reservoirs, the reservoir parameters such as porosity, clay content, and thickness vary with location. So the information from traditional fluid substitution just at the well is limited. By assuming a rock physics model linking the elastic properties to porosity and mineralogy, we conducted seismic forward modeling and AVO attributes computation on a three-layer earth model with varying porosity, clay content, and formation thickness. Then we analyzed the relations between AVO attributes at wet reservoirs and those at the same but gas reservoirs. We arrived at their linear relations within the assumption framework used in the forward modeling. Their linear relations make it possible to directly conduct fluid substitution on seismic AVO attributes. Finally, we applied these linear relations for fluid substitution on seismic data and identified gas reservoirs by the cross-plot between the AVO attributes from seismic data and those from seismic data after direct fluid substitution.

关键词： fluid substitution AVO gas reservoir Gassmann's equation rock physics

Self-adapting extraction of matrix mineral bulk modulus and verification of fluid substitution

在线全文

学校读者我要写书评

暂无评论

Applied Geophysics 2011年第2期8卷 110-116,176页

作者：林凯熊晓军杨晓贺振华曹俊兴张玺华王萍成都理工大学油气藏地质及开发工程国家重点实验室四川成都610059 中国石油集团川庆钻探工程有限公司地球物理勘探公司四川成都610213

Gassmann＇s equations are commonly used for predicting seismic wave velocity in rock physics *** the input matrix mineral bulk modulus parameters are not accurate,which greatly influences the prediction *** this paper,combining the Russell fluid factor with the Gassman-Biot-Geertsma equation and introducing the dry-rock Poisson＇s ratio,we propose an effective matrix mineral bulk modulus extraction *** method can adaptively invert the equivalent matrix mineral bulk modulus to apply the Gassmann equation to fluid substitution of complex carbonate reservoirs and increase the fluid prediction *** verification of the actual material fluid substitution also shows that this method is reliable,efficient,and adaptable.

关键词： Self-adapting matrix mineral bulk modulus fluid substitution dry rock Poisson's ratio

Velocity dispersion and fluid substitution in sandstone under partially saturated conditions

在线全文

学校读者我要写书评

暂无评论

Applied Geophysics 2018年第2期15卷 188-196,361,362页

作者： Ma Xiao-Yi Wang Shang-Xu Zhao Jian-Guo Yin Han-Jun Zhao Li-Ming State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum (Beijing) Beijing 102249 China

The elastic moduli of four sandstone samples are measured at seismic （2-2000 Hz） and ultrasonic （1 MHz） frequencies and water- and glycerin-saturated conditions. We observe that the high-permeability samples under partially water-saturated conditions and the low-permeability samples under partially glycerin-saturated conditions show little dispersion at low frequencies （2-2000 Hz）. However, the high-permeability samples under partially glycerin-saturated conditions and the low-permeability samples under partially water-saturated conditions produce strong dispersion in the same frequency range （2-2000 Hz）. This suggests that fluid mobility largely controls the pore-fluid movement and pore pressure in a porous medium. High fluid mobility facilitates pore-pressure equilibration either between pores or between heterogeneous regions, resulting in a low-frequency domain where the Gassmann equations are valid. In contrast, low fluid mobility produces pressure gradients even at seismic frequencies, and thus dispersion. The latter shows a systematic shift to lower frequencies with decreasing mobility. Sandstone samples showed variations in Vp as a function of fluid saturation. We explore the applicability of the Gassmann model on sandstone rocks. Two theoretical bounds for the P-velocity are known, the Gassmann-Wood and Gassmann-Hill limits. The observations confirm the effect of wave-induced flow on the transition from the Gassmann-Wood to the Gassmann-Hill limit. With decreasing fluid mobility, the P-velocity at 2-2000 Hz moves from the Gassmann-Wood boundary to the Gassmann-Hill boundary. In addition,, we investigate the mechanisms responsible for this transition.

关键词： Sandstone saturation P-wave dispersion Gassmann fluid substitution

Reservoir fluid substitution Effect in Heterogeneous Seismic Model

在线全文

学校读者我要写书评

暂无评论

Open Journal of Yangtze Oil and Gas 2021年第3期6卷 98-106页

作者： Wei Zhang Mingjing Gui Qing Zhao Mengling Liu Xinyue Liu Xinyi Zhang College of Geophysics and Petroleum Resources Yangtze University Wuhan China Key Laboratory of Exploration Technology for Oil and Gas Resources of Ministry of Education Yangtze University Wuhan China

Based on the difference of wave impedance between sand layer and surrounding rock, the seismic wave numerical simulation software, Tesseral-2D is used to establish the sandstone formation model containing water, oil and gas respectively, and the three models are treated by post-stack time offset under the conditions of defined channel spacing, wavelet frequency and wave velocity of different rock mass, and the root means square amplitude difference attribute profile under the condition of water-filled oil-filled and gas-filled oil-filled is obtained. From this, it can be obtained that after oil-gas substitution occurs in weak non-mean reservoirs, the root-mean-square amplitude difference from the reservoir to the lower part of the reservoir experiences a mutation process from a positive maximum to a negative maximum, while after oil-water substitution, the root-mean-square amplitude difference from the reservoir to the lower part of the reservoir experiences a mutation process from zero to a positive maximum. For a strong heterogeneous reservoir. Therefore, for Weak inhomogeneous media similar to tight sandstone, the root-mean-square amplitude difference attribute can be used to detect the distribution of fluid in the actual gas drive or water drive oil recovery process.

关键词： Sandstone Model Tesseral-2D Software Root-Mean-Square Amplitude Difference Strong and Weak Heterogeneous fluid substitution

On the fluid Dependence of Seismic Anisotropy:Beyond Biot-Gassmann

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Earth Science 2018年第6期29卷 1335-1339页

作者： Leon Thomsen University of Houston Delta Geophysics

This work addresses the question of the fluid dependence of the non-dimensional parameters of seismic anisotropy. It extends the classic theory of the fluid-dependence of elasticity, and applies the approximation of weak seismic anisotropy. The analysis shows that reliance upon the classic theory leads to oversimplified conclusions. Extending the classic theory introduces new parameters（which must be experimentally determined） into the conclusions, making their application in the field context highly problematic.

关键词： Biot Gassmann incompressibility fluids fluid substitution pore compressibility

A rock-physical modeling method for carbonate reservoirs at seismic scale

在线全文

学校读者我要写书评

暂无评论

Applied Geophysics 2013年第1期10卷 1-14,117页

作者：李景叶陈小宏中国石油大学(北京)油气资源与探测国家重点实验室北京102249 中国石油大学CNPC物探重点实验室北京102249

Strong heterogeneity and complex pore systems of carbonate reservoir rock make its rock physics model building and fluid substitution difficult and complex. However, rock physics models connect reservoir parameters with seismic parameters and fluid substitution is the most effective tool for reservoir prediction and quantitative characterization. On the basis of analyzing complex carbonate reservoir pore structures and heterogeneity at seismic scale, we use the gridding method to divide carbonate rock into homogeneous blocks with independent rock parameters and calculate the elastic moduli of dry rock units step by step using different rock physics models based on pore origin and structural feature. Then, the elastic moduli of rocks saturated with different fluids are obtained using fluid substitution based on different pore connectivity. Based on the calculated elastic moduli of rock units, the Hashin-Shtrikman-Walpole elastic boundary theory is adopted to calculate the carbonate elastic parameters at seismic scale. The calculation and analysis of carbonate models with different combinations of pore types demonstrate the effects of pore type on rock elastic parameters. The simulated result is consistent with our knowledge of real data.

关键词： Seismic scale fluid substitution carbonate rock rock physics modeling^heterogeneity |

Calculations of rock matrix modulus based on a linear regression relation

在线全文

学校读者我要写书评

暂无评论

Applied Geophysics 2011年第3期8卷 155-162,239页

作者：贺锡雷贺振华汪瑞良王绪本蒋炼油气藏地质及开发工程国家重点实验室成都理工大学 610059 中海石油(中国)有限公司深圳分公司 518067

The rock matrix bulk modulus or its inverse, the compressive coefficient, is an important input parameter for fluid substitution by the Biot-Gassmann equation in reservoir prediction. However, it is not easy to accurately estimate the bulk modulus by using conventional methods. In this paper, we present a new linear regression equation for calculating the parameter. In order to get this equation, we first derive a simplified Gassmann equation by using a reasonable assumption in which the compressive coefficient of the saturated pore fluid is much greater than the rock matrix, and, second, we use the Eshelby- Walsh relation to replace the equivalent modulus of a dry rock in the Gassmann equation. Results from the rock physics analysis of rock sample from a carbonate area show that rock matrix compressive coefficients calculated with water-saturated and dry rock samples using the linear regression method are very close （their error is less than 1%）. This means the new method is accurate and reliable.

关键词： Bulk modulus rock matrix fluid substitution rock physics linear regression