关键词: 岩性解释, 弹性, 模量, 饱和度, 上覆盖岩层压力

Abstract: Eight samples with different lithologic characters are collected from sandstone-conglom-erate reservoirs with positive rhythm. Under five kinds of saturation fully saturated states-with water(S_w=100%),oil(S_o=100%),gas(S_g=100%),irreducible water and residual oil,the velocities of compressional and shear waves(V_p,V_s)and mechanical pararneters(Bulkmodulus K, Young's modulus E, Lame constant λ, Rigidity modulus μ, Poisson's ratio v andDensity ρ)are measured precisely under different effective overburden pressure in laboratory. The results of this study suggest that:(1)Elastic moduli E,K,λ,μ of rock increase as pres-sure ΔP increases,variation of E,K,λ,μ with ΔP is more sensitive in low-pressure rangethan in high pressure range. (2)Under the same saturation state,the range of elastic modulivs. effective overburden pressure curves is controlled by lithological variations in the samereservoir. (3)Under the same pressure(surface to subsurface)and in three systems(oil-water,oil-gas,gas-water),elastic modulus in each case is a linear function of saturation. (4)Elasticmodulus vs. pressure curves have evident zonal distribution under different saturation state. (5) There is a good correlative relationship between the dynamic and static compressibilitycoefficient in eight samples.

Key words: lithology interpretation, elastic, modulus, saturation, overburden pressure