Reservoir management optimization requires a detailedrndescription of the geometry and the properties of the reservoir.rnFor horizontal wells, knowing accurately the position of thernborehole in the reservoir is critical. However, seismicrntechniques do not have sufficient resolution to provide thernposition of the well with respect to the reservoir boundariesrnwith desired accuracy. Sonic measurement on the other handrnhas the potential to provide such information. We conductedrnexperiments in horizontal wells in Oman using a commercialrnmulti-receiver sonic tool modified for imaging, with extendedrnspacing between the transmitter and the receivers. Althoughrnthe tool characteristics are not optimized for the imaging, wernobtained interesting results when the reflectors have sufficientrnstrength, thus showing the potential of this technique. The preprocessedrnand migrated sonic images provided usefulrninformation on the geometry of the reservoir, which could berncompared with seismic interpretation and field knowledge.rnFurthermore, we developed a specific processing techniquernthat uses the four different waveforms acquired around therntool at each receiver station to separate the reflections comingrnfrom above the well and the ones coming from below. In thisrnway, we could obtain images that could be interpreted morerneasily. In some instances, the position of the reservoirrnboundaries could be determined with an accuracy of 1 m up torna maximum distance of 10 m.
展开▼
