Abstract：Reservoir description in Liu-3 borehole area in the Yishu basin was made by us- ing the following geophysical interpretation methods.Lateral porosity variation prediction method based on triple-element model,the method removes high-side porosity that results from shale influence and is calcu-lated by conventional method.t。 contour maps of weak reflectors are plotted by interpreting instantaneous-phase sections, so that minute structure interpretation of reservoir series can be achieved desirably.Time-depth conversion ls done by using the averaged velocity field which is derived from the top and bottom velocity flelds of a reservoir with the use of velocity spectrum data,thus greatly improving structural map.The methods brlng satisfactory effect in Llu-3 borehole area.
