--Data Wells Drilled
       In Phase I, six wells were drilled to gather data, delineate the field, and evaluate completion and production techniques. Each of these wells was drilled in different areas of the field to determine the producing characteristics at various field positions. Conventional suites of logs and multiple sidewall cores were obtained in all of the NDP data wells. In addition, 61.9 m (203 ft) of full core was obtained from one new well and a magnetic resonance tool was run for comparison to the core analysis. Basic core data were measured for each foot of core, and special core analysis were performed on the full core. The core data were used to calibrate the logs and determine pay distribution in each zone. A detailed core-calibrated log analysis of saturations and porosity was applied to the digitized logs to determine the productive and the water zones in each interval. The application of porosity/permeability transforms and relative permeability data to each zone yielded flow capacity data for each interval. Details are given in the first annual technical progress report (First Annual).

        --Advanced Log Analysis
       To evaluate the highly laminated micro-reservoirs that make up the pay zones in the Brushy Canyon interval, a log evaluation technique was developed to identify pay that is laminated with wet zones. Using transmissibility values to calculate production from the various zones for all 16 wells in the NDP, results show that while the bulk of the oil production at the NDP comes from the "L" sandstone, much of the water is produced from the "K" and "K-2" sandstone, if the latter zone is present. By properly identifying productive pay intervals, oil recovery from the Brushy Canyon reservoir at the NDP is calculated to be 16.6%, rather than the 10% as initially estimated. This methodology for identifying net pay in complex reservoirs can be applied in other highly laminated sandstone formations. The methodology, outlined in the first annual report (First Annual), was used to identify net pay and estimate flow capacity for each interval (Second Annual). The advanced log analysis technique is also described in two SPE papers (SPE Paper 38916) and (SPE Paper 39775).

        --Geophysical Results
       Vertical seismic profiles and a 3-D seismic survey were acquired to assist in interwell correlations and facies prediction. By conducting pre-survey VSP wave testing and by careful processing of 3-D seismic data, the thin-bed turbidite reservoirs at the NDP could be imaged, and the individual Brushy Canyon sandstones could be resolved. The interpreted seismic data indicated that the NDP may be highly compartmentalized, and that some of the compartments, for some sand sequences in the "L" zone, may be much smaller than 300 acres. Results of seismic data and other interpretations are being used for targeted drilling in high-grade areas of the NDP. Seismic acquisition is described in the first annual report (First Annual Report) and seismic analysis is provided in the second annual report (Second Annual Report), and the results are discussed in two technical papers (GEOPHYSICS Papers). As new wells and data became available, interpretation of the seismic results has continued (Fifth Annual).

        --Geostatistics and Seismic Attribute Analysis
       The potential value of geostatistical techniques for estimating interwell reservoir properties, with infill drilling as a possible goal, was investigated. However, NDP wells primarily cover the center part of the initial seismic survey, so a new technique was developed to extrapolate reservoir properties beyond the area directly constrained by wells. This new technique utilizes a non-linear multivariable regression (Neural Networks) with seismic attributes as inputs and porosity, water saturation, and net pay as outputs. A Fuzzy Ranking System can help decide which seismic attributes are most useful for evaluating reservoir properties. The regression equations allow the prediction of the three reservoir properties in areas without direct well control, and the resulting computed maps, such as hydrocarbon pore volume, can be generated fieldwide. Results suggest that predictions of interwell and fieldwide reservoir properties are possible Details of the methodology are available (Third Annual Report) (SPE Paper 56733).

        --Reservoir Modeling and Simulation
       After a fieldwide geological model of the NDP was completed, a detailed simulation model of a proposed pilot area (simulation area) was developed for the most productive "L" sand (First Annual Report). Reservoir simulation studies were performed to evaluate various injection methods, including waterflooding, lean gas, and carbon dioxide, for the pilot area (Second & Third Annual Reports). Immiscible gas injection for pressure maintenance in the proposed pilot area at the NDP was ruled out because of low reservoir pressure and compartmentalization of productive intervals. The low permeabilities and relative permeability effects may preclude waterflooding at the NDP. Miscible CO2 flooding may be a viable method at the NDP, and areas of the field already under production could be candidates for miscible CO2 injection, but a low-cost source of the gas is not available in the vicinity of the NDP. Injection of immiscible hydrocarbon gas for pressure maintenance may be viable in undeveloped regions if those areas are not pressure depleted or compartmentalized and if injection is initiated early. The results of the reservoir studies prompted the decision to shift consideration of a pressure maintenance pilot project into Phase 2, when new areas of the NDP are drilled.

        --Technology Transfer Activities
       Technology Transfer of the data and results from the NDP project have been a major component of the project. All of the technology transfer activities are listed in the major section in Technology Transfer (Technology Transfer). Interest in this project has been high and the application of results from the project has been useful in other Delaware fields. The transfer of technology from Phase 2 will continue to be a major component of the project.

        --Modified Plans
       The original Statement of Work included a pressure maintenance pilot project in a developed area of the field. The proposed pressure maintenance injection was not conducted because the pilot area was pressure depleted, and the seismic results suggest the pilot area is compartmentalized. Because reservoir discontinuities would reduce the effectiveness of any injection scheme, the pilot area will be reconsidered in Phase 2 of the project if a more continuous part of the reservoir can be located that has sufficient reservoir pressure.
The major emphasis in Phase 2 is to use the advanced characterization results to design extended-reach/horizontal wells to tap into predicted "sweet spots" that are inaccessible with conventional vertical wells.