A Methodology for the Assessment of Unconventional (Continuous) Resources with an Application to the Greater Natural Buttes Gas Field, Utah

摘要: The Greater Natural Buttes tight natural gas field is an unconventional (continuous) accumulation in the Uinta Basin, Utah, that began production early 1950s from Upper Cretaceous Mesaverde Group. Three years later, was extended to Eocene Wasatch Formation. With exclusion of 1100 non-productive (“dry”) wells, we estimate final recovery 2500 producing wells existing 2007 will be about 1.7 trillion standard cubic feet (TSCF) (48.2 billion meters (BCM)). use estimated ultimate (EUR) per well common assessments resources, and it one main sources information forecast undiscovered resources. Each calculated value has associated drainage area generally varies can mathematically subdivided into elemental subareas constant size shape called cells. Recovery 5-acre cells at shows spatial correlation; hence, statistical approaches ignore this correlation when inferring EUR values for untested do not take full advantage all contained data. More critically, resulting models match style fluctuations observed nature. This study takes a new approach by applying statistics model geographical variation cell taking account influence fractures. We applied sequential indicator simulation cells, while mapping obtained Gaussian provide multiple versions reality (realizations) having equal chances being correct model. For each realization, summation drained allowed preparation stochastic prediction which range between 2.6 3.4 TSCF (73.6 96.3 BCM) with mean 2.9 (82.1 Buttes. A second illustrates application multiple-point assess hypothetical frontier there no but regarded as similar