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EX-99.3  GLOSSARY OF SELECTED OIL & GAS TERMS

         The following are abbreviations and definitions of certain terms
commonly used in the oil and natural gas industry and this Prospectus.

         "AMI." Area of Mutual Interest. A federal income tax term used in
         allocating geophysical and geological costs to certain properties. A
         large-scale geophysical survey may indicate several areas of interest.
         The cost of the survey must be allocated to each area of interest, and
         when leases are obtained therein, the geophysical costs become part of
         the basis of the property.

         "Bbl." One stock tank barrel, or 42 U.S. gallons liquid volume, used
         herein in reference to crude oil or other liquid hydrocarbons.

         "Boe." Barrel oil equivalents.

         "COMPLETED WELL." The completion of a well or a completed well refers
         to the installation of permanent equipment for the production of oil or
         natural gas, or in the case of a dry hole, the reporting of abandonment
         to the appropriate agency.

         "DEVELOPED ACREAGE." Acreage spaced or assignable to productive wells.

         "DEVELOPMENT WELL." A well drilled within the proven boundaries of an
         oil or natural gas reservoir with the intention of completing the
         strategraphic horizon known to be productive.

         "DRY HOLE." An exploratory or development well found to be incapable of
         producing either oil and natural gas in sufficient economic quantities
         to justify completion of a well.

         "EXPLORATORY WELL." A well drilled within no proven boundaries of an
         oil or natural gas reservoir.

         "GROSS ACRE." An acre in which a working interest is owned.

         "GROSS WELL(S)." A gross well is a well in which a working interest is
         owned. The number of gross wells is the total number of wells in which
         working interests are owned.

         "INFILL DRILLING." Drilling of a well between known producing wells to
         better exploit the reservoir.

         "Mcf." One thousand cubic feet of natural gas.

         "NET ACRE(S)." A net acre is deemed to exist when the sum of fractional
         ownership working interests in gross acres equals one. The total of net
         acres is the sum of the fractional working interests owned in gross
         acres expressed as whole numbers and percentages thereof.

         "NET WELL(S)." A net well is deemed to exist when the sum of the
         fractional ownership working interests in gross wells equals one. The
         number of net wells is the sum of the fractional working interests
         owned in gross wells expressed as whole numbers and percentages
         thereof.

         "OVERRIDING ROYALTY INTEREST." An interest in an oil and/or natural gas
         property entitling the owner to a share of oil and natural gas
         production free of costs of production.

         "PRESENT VALUE OF ESTIMATED FUTURE NET REVENUES." The present value of
         estimated future net revenues is an estimate of future net revenues
         from a property at its acquisition date, at December 31, 1997, or as
         otherwise indicated, after deducting production and ad valorem taxes,
         future capital costs and operating expenses, but before deducting
         federal income taxes. The future net revenues have been discounted at
         an annual rate of 10% to determine their "present value." The present
         value is shown to indicate the effect of time on the value of the net
         revenue stream and should not be construed as being the fair market
         value of the properties. Estimates have been made using constant oil
         and natural gas 



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         prices and operating costs at the acquisition date, at December 31,
         1997, or as otherwise indicated. POWER believes that the present value
         of estimated future net revenues before income taxes, while not in
         accordance with generally accepted accounting principles, is an
         important financial measure used by investors and independent oil and
         natural gas producers for evaluating the relative significance of oil
         and natural gas properties and acquisitions.

         "PRODUCING WELL," "PRODUCTION WELL" OR "PRODUCTIVE WELL." A well that
         is producing oil or natural gas or that is capable of production.

         "PROVED BEHIND-PIPE." Proved reserves that are currently behind the
         pipe of an existing well that are expected to be productive due to the
         wells log characteristics and the analogous production of other wells
         in the immediate vicinity.

         "PROVED DEVELOPED RESERVES." Proved developed reserves are those
         quantities of oil, natural gas and NGLs that, upon analysis of
         geological and engineering data, are expected with reasonable certainty
         to be recoverable in the future from known oil and natural gas
         reservoirs under existing economic and operating conditions. This
         classification includes: (a) proved developed producing reserves, which
         are those expected to be recovered from currently producing zones under
         continuation of present operating methods; and (b) proved developed
         nonproducing reserves, which consist of (i) reserves from wells that
         have been completed and tested but are not yet producing due to lack of
         market or minor completion problems that are expected to be corrected,
         and (ii) reserves currently behind the pipe in existing wells which are
         expected to be productive due to both the well log characteristics and
         analogous production in the immediate vicinity of the well.

         "PROVED NONPRODUCING RESERVES." Proved nonproducing reserves include
         proved behind-pipe reserves and proved undeveloped reserves.

         "PROVED RESERVES." The estimated quantities of crude oil, natural gas
         and NGLs which geological and engineering data demonstrate with
         reasonable certainty to be recoverable in future years from known
         reservoirs under existing economic and operating conditions.

         "PROVED UNDEVELOPED RESERVES." Proved reserves that may be expected to
         be recovered from existing wells that will require a relatively major
         expenditure to develop or from undrilled acreage adjacent to productive
         units that are reasonably certain of production when drilled.

         "UNDEVELOPED ACREAGE." As defined by the Commission, undeveloped
         acreage is considered to be lease acreage on which wells have not been
         drilled or completed to a point that would permit the production of
         commercial quantities of oil and natural gas regardless of whether such
         acreage contains proved reserves. in connection herewith.

         "WORKING INTEREST." The operating interest that gives the owner the
         right to drill, produce and conduct operating activities on the
         property and to a share of production, subject to all royalties,
         overriding royalties and other burdens and to all costs of exploration,
         development and operations and all risks.