RIVERTON DOME GAS EXPLORATION AND STIMULATION TECHNOL- OGY DEMONSTRATION, WIND RIVER BASIN, WYOMING

1999 Oil and Gas Conference

Ronald C. Surdam ; Zunsheng Jiao ; Nicholas K. Boyd

Others  :  http://www.netl.doe.gov/publications/proceedings/99/99oilgas/ng2b-6.pdf
PID  :  47464

来源: CEUR

【 摘 要 】

The new exploration technology for basin center gas accumulations developed by R.C. Surdam and Associates at the Institute for Energy Research, University of Wyoming, was applied to the Riverton Dome 3-D seismic area. Application of the technology resulted in the development of important new exploration leads in the Frontier, Muddy, and Nugget formations. The new leads are adjacent to a major north-south trending fault, which is downdip from the crest of the major structure in the area.In a blind test, the drilling results from six new Muddy test wells were accurately predicted. The initial production values, IP, for the six test wells ranged from < one mmcf/day to four mmcf/day. The three wells with the highest IP values (i.e., three to four mmcf/day) were drilled into an intense velocity anomaly (i.e., anomalously slow velocities). The well drilled at the edge of the velocity anomaly had an IP value of one mmcf/day, and the two wells drilled outside of the velocity anomaly had IP values of < one mmcf/day and are presently shut in. Based on these test results, it is concluded that the new IER exploration strategy for detecting and delineating commercial, anomalously pressured gas accumulations is valid in the southwestern portions of the Wind River Basin, and can be utilized to significantly reduce exploration risk and to increase profitability of so-called basin center gas accumulations.Most importantly, this study strongly suggests that a prime exploration prospect exists in the Riverton Dome 3-D seismic survey area. At this location, the new IER conceptual model and exploration technology can be tested in three tartargeted formations (i.e., the Frontier, Muddy, and Nugget formations) in a single well. At the prospect, in each of the formations there is an intense velocity anomaly that is 1800 to 1900 ms slower than would be predicted by the regional velocity - depth gradient. A velocity anomaly of this magnitude can only be explained by the presence of significant gas accumulations. Thus, it is concluded that a well drilled at CDP 124896 in the Riverton Dome 3-D seismic survey is not only an ideal test of the IER exploration technology, but also the highest priority drill site for so-called basin center gas accumulations within the survey area.