Abstract:The Ordovician Carbonate fracture-cave reservoir is the major reservoir type in Tahe Oilfield. Improving the “string” imaging accuracy and exquisite depicting the internal characteristic of the fracture-cave bodies are one of the key research problems about seismic exploration in this region, combined with exploration cost, carring out seismic geometry design about the fracture-cave target bodies is very necessary. Through building the three-dimensional cave reservoir geological model about work area, to obtain the migration image illumination energy with these cave reservoir target bodies by using Guassian beam bi-directional illumination technology based on seismic geometry. Under the condition of the same fold about seismic geometry, quantitatively demonstrates different illumination effect of acquisition parameters (putting point on the bin and azimuth) on cave bodies, based on the results to choose the best parameters, providing theoretical guidance for field seismic geometry design.