Abstract:

The fractured-vuggy system of the Ordovician carbonate in Tarim Basin is defined as network-like reservoirs composed of effective fractures and vugs formed by multistage and multicycle of dissolutions,diagenesis, and fracturing.Generally,the scale and extension of fractured-vuggy system is critical to hydrocarbon accumulation in the Ordovician and stable and high production from Ordovician reservoirs.The present seismic technologies are still insufficient in detecting and distinguishing single small fractures or rugs.However,larger fracturedvuggy system consisted of many fractures and vuggies can be effectively detected and predicted,especially with the help of seismic wave dynamic parameters,which are much reliable than kinematics parameters.The detection of fractured-vuggy system can be achieved through integration of the following techniques:coherence analysis, amplitude attributes,multi-scale fracture detection,frequency difference analysis(FDA),and wave impendence inversion.However,fractured-vuggy systems of different origins and sizes in different areas require different combinations of these techniques and methods.

Key words: fractured-vuggy system, seismic response and prediction, carbonate rock, Tarim Basin