An inorganic thermal maturity indicator in the gas-condensate to dry gas preservation window: [sup 40]Ar/[sup 39]Ar feasibility study

Conference · Mon Jan 01 04:00:00 EST 1996 · AAPG Bulletin

OSTI ID:6566981

Copeland, P ^[1]; Skirius, C; Claxton, B ^[2]

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1. Univ. of Houston, TX (United States)
2. Amoco Production Co., Houston, TX (United States)

Core samples of Devonian Gilwood Sandstone and Shale from the Alberta Basin, North Central Alberta, Canada were used to investigate the feasibility of using [sup 40]Ar/[sup 39]Ar age spectrum results as an inorganic indicator of thermal maturity. The core samples are from several wells in the Pine Creek and Kaybob South field areas and were chosen because (1) the samples are presently in the gas-condensate to dry gas preservation windows, (2) the sandstones contain appropriate feldspars for Ar analysis, and (3) the section contains interbedded shales for assessment of thermal maturity. [sup 40]Ar/[sup 39]Ar age spectrum results within the thermal range ([approx]130 degrees C to [approx]250 degrees C) from sandstone detrital feldspar grains are compared to vitrinite reflectance measurements from interbedded shales. The temperature history of the samples as indicated by [sup 40]Ar/[sup 39]Ar age spectrum results is correlated to vitrinite reflectance measurements in order to arrive at an inorganic thermal calibration. Such an inorganic thermal calibration can then be tested in areas or basins that do not have shales to derive organic data such as vitrinite reflectance measurements or in areas of very old sediments ([approx]Silurian or older) where organic thermal maturity indicators are not well calibrated. Unique advantages of the [sup 40]Ar/[sup 39]Ar method for application to petroleum exploration within sedimentary basins are that it can simultaneously provide information about (1) the time of basin heating, (2) the temperature of a heating episode, (3) the duration of a heating episode, and (4) the age of the sediment source or provenance.

• OSTI ID: 6566981
• Report Number(s): CONF-960527--
• Conference Information: Journal Name: AAPG Bulletin Journal Volume: 5
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200 -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200* -- Natural Gas-- Reserves
Geology
& Exploration
ALBERTA
CANADA
DEVELOPED COUNTRIES
EXPLORATION
GAS CONDENSATE FIELDS
GEOLOGIC DEPOSITS
GEOLOGIC STRUCTURES
HYDROCARBONS
MATURATION
MINERAL RESOURCES
NATURAL GAS DEPOSITS
NATURAL GAS FIELDS
NORTH AMERICA
ORGANIC COMPOUNDS
PETROLEUM DEPOSITS
RESERVOIR ROCK
RESOURCES
SEDIMENTARY BASINS