V. DATA QUALITY AND PRESENTATION
Core analysis data in this database were compiled from the original
paper copy Core Analysis Reports or from Well History Reports, with some
additional or modified information:
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Core intervals with no core analysis data, usually reported as “–1.0” on
core analysis reports were not included in the database. These intervals
usually correspond with shaly intervals or intervals of poor core condition.
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Core depths and sample lengths recorded in imperial units were converted
to metric units. This conversion and rounding of numbers have caused
slight discrepancies in depths between the cored intervals and sample depths.
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Lithological descriptions have been standardized, and where possible, abbreviations
were changed to full descriptions. For some wells abbreviations could not
be interpreted and these wells have abbreviated lithological descriptions
in the database.
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Data quality was assessed and only one well (Sable Island C-67, analyzed
in 1967) was considered to have less reliable data and is marked as
"Questionable" in the database. Most analyses conducted before 1970
are considered less reliable than those conducted after 1970 (Monohan,
Core Laboratories, pers. com., 1998). A different method known as the Retort
Method (Monicard, 1980), (also known
as the Summation of Fluids Technique), was in use in the earlier days which
might give questionable results.
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Only data from Rotary type sidewall cores were included in the database.
Core analysis data from Percussion type sidewall cores are believed to
introduce microfractures in the coring process, resulting in overestimated
porosity and permeability values.
Core analysis procedures; including cleaning procedures are often
not recorded in the core analysis reports. As this information is not included
in this database, consult the original core analysis reports for this information.
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