Explanation of Contents

This area reports the results of the 2006 assessment of undiscovered, risked, technically recoverable resources (UTRR), or “geological endowment” for the Alaska Outer Continental Shelf (OCS).  Economic assessment results for the Alaska OCS are given elsewhere in this report.  Each “assessment province” corresponds to an Alaska OCS “planning area” and the terms are interchangeable.  For each assessment province, written reports in Adobe-Acrobat (pdf) format describe the geology and assessment results for provinces (province summary) and plays (play summary).  The written reports are supplemented by downloadable files for play input data and computer output files (in Excel or text format) that make the assessment data available to potential users.  The downloadable files are described below:

“Assessment Results by Play” are downloadable Excel-format (xls) files that report assessment results (undiscovered, technically-recoverable, risked or “UTRR” resources) for individual plays and for five commodities (BOE, oil, condensate, free gas, and solution gas) at the 95% (F95), mean, and 5% (F05) probability-of-existence levels, all summed to the province level.  These tables are also presented in the Adobe Acrobat-format (pdf) province summaries.

“Assessment Results by Commodity” are downloadable Excel-format (xls) files that report province or play assessment results (undiscovered, technically-recoverable, risked or “UTRR” resources) for five commodities (BOE, oil, condensate, free gas, and solution gas) at 30 probability levels across the entire range of possible commodity volumes.  In the case of provinces, individual plays are not reported.  For provinces, these Excel files were prepared from the province aggregation text files reported by the GRASP computer model.  In the case of plays, these Excel files were prepared from the play resource aggregation text files (“psum.out”) reported by the PSUM module in the GRASP computer model.  These tables are also presented in the Adobe Acrobat-format (pdf) province and play summaries.

“Input Data Tables” are downloadable Excel-format (xls) files that report the probability distributions, constants, probability values, play risk models, and other input data that were entered to the GRASP (computer) model for use in calculating undiscovered, technically-recoverable, risked or “UTRR” resources for individual plays.  These tables are also presented in the Adobe Acrobat-format (pdf) play summaries.

“Pool Size Models” are downloadable MS-DOS text-format (txt) files that are reported out of the PSRK module of the GRASP computer model (“psrk.out”).  The “psrk” files report detailed cumulative probability distributions for unrisked or conditional pool resources at 30 probability levels, ranging from F100 to F00, for each of the individual pools in any play.  (Typically, 1 to 50 pools are forecast by the prospect numbers and risk models for the play.)  For each pool, probability distributions for five separate commodities are reported (BOE, oil, condensate [“COil”], free gas [“Gas”, including both non-associated gas and gas-cap gas], and solution gas [“SGas”]).  The pools reported by the PSRK module of the GRASP computer model thus represent the “undiscovered fields” modeled for the play.

“Simulation Pool Statistics” are downloadable Excel-format (xls) files that report statistics for the thousands of individual “simulation pools” created as the products of individual sampling runs (iterated thousands of times) in a GRASP play model simulation.  These Excel files were prepared from statistical summaries of the sizes of the simulation pools that are reported as text files (“fieldsize.out”) by the FIELDSIZE module in the GRASP computer model.  Each “fieldsize” simulation pool basically represents the product of a succession of sampling run “hits” on multiple input probability distributions or constants (pool area, pay thickness, oil yield, solution gas yield, etc.).  The thousands of “fieldsize” simulation pools are then used to build models for “psrk” pools, to calculate overall play resources, and to assess economic potential.  These tables are also presented in the Adobe Acrobat-format (pdf) play summaries.