Seismic response properties of Ordovician carbonate rock oil pools in Lunnan Region

Tarim Basin are evidence:1.the impedance differentiae of the carbonate rocks with well developed fractures change smaller

the reflection energy decreases thus resulting in decrease of reflection amplitude;2.high frequency of the fracture developed area damp out quickly

so the reflection frequency decreases;3.if the fractures are filled with liquid

the ratio of formation absorbing seismic wave will considerably increase;4.the wave impedance of fracture fluid is much lower than that of fractures with no fluid.According to drilling statistical analysis

the coincidence rates of the first three terms are as high as 87%～90%

but the last one is only 65% since reservoir spaces are extremely heterogeneous and this effects lateral resolution.