Abstract: 3D Reservoir Description at Multiple Scales
South Powderhorn Field was discovered in 1959 by Quintana Petroleum and Humble Oil and has since produced 50+ BCFG out of a series of Miocene aged channel sands. By early 1996, production had declined to less than 0.5 MMCF/day. 3DX Technologies, along with Prime Operating took a farmout on the property and shot a 3D survey to revitalize the field. The companies have applied several reservoir description technologies to gain a better understanding of the reservoir. Through the use of these technologies, the companies have drilled 9 wells and boosted production to 12 MMCF/day.
3D seismic over Powderhorn field delineated the three producing channels, and showed a significant change from the previous interpretation of the stratigraphy of one of the key producing levels. The 4650 sand was previously interpreted (via 2D seismic and subsurface) as laid down in a pure fluvial environment. Detailed analysis of the 3D data; including inversion, AVO analysis, and geostatistics, indicated a different depositional environment far this sand. In order to confirm this new depositional model Formation Micro Imager and detailed core analysis were performed on several of the early wells. These tools, combined with normal E-logs, provided an image of the reservoir at four distinct scales. Incorporation of these different tools resulted in confirmation of the alternative model.
Drilling into this reservoir with the revised depositional model has resulted in 4 successful wells. In addition to the economic success, these tools have provided cross data calibration for understanding of other producing reservoirs in the area.
AAPG Search and Discovery Article #90937©1998 AAPG Annual Convention and Exhibition, Salt Lake City, Utah