f Areal mapping of porosity by the combined use of ultrasonic, sonic and 3d seismic data

In this paper we present a study from a major oil & gas field in the North Sea. Hydrocarbons are trapped within three major tilted fault blocks, and this particular study is restricted to an area within one of the fault blocks. A system of stacked river channels is situated above the main reservoir, and significant oil reserves have been proven within this secondary target. The objective of the study is to investigate the feasibility of mapping the channel sands between 14 wells in the area. Three of the wells are situated in the gas zone while the remaining 11 wells are located in the oil zone. In the following the discussion is concentrated on two possible channel systems; named the "upper" and "lower" formations, respectively.