储层砂岩波阻抗及拉梅常数实验研究

地层条件下应用岩石物理参数测试系统(MTS)测试了岩石纵横波速度,结合已研究成果,根据实验数 据和计算结果总结了波阻抗和拉梅常数与不同地层条件的关系,得到地表条件下岩样(饱气)的波阻抗随岩石孔 隙度的增加而减小。同一个岩样(饱水)的波阻抗随着模拟地层深度的增加而增加。在各自相对应的模拟地层 深度条件下,饱水岩样的纵波阻抗和拉梅常数值均明显大于饱气岩样的数值,但横波阻抗变化很小。

Experimental Study on Wave Impedance and Lame Constant of Reservoir Sandstones

Forty petrophysic parameters, P-wave and S-wave velocity data of Tertiary sandstones from Southern China Sea were tested using the MTS machine under different formation pressures and temperatures. Based on the data, the wave impedance, Lame constant a-nd other parameters are calculated, and the relationships between wave impedance, Lame constant and formation conditions are discussed. The conclusions from our experimental study are as follows:(a)Wave impedance decreases with the increase of porosity of sandstones(dry samples), but the variations of Lame constant are uncertain under the conditions of room temperature and pressure;(b) Wave impedance of sandstone samples(saturated by water)increases with the increase of the formation pressures and temperatures, but the variations of Lame constant is uncertain;(c)P-wave impedance and Lame constant of the sandstone samples(saturated by water)are larger than those of dry sandstones under the corresponding for- mation pressures and temperatures.