Amplitude versus offset gradient modeling over a Minnelusa field

Journal Article · Fri Apr 01 04:00:00 EST 1988 · Mt. Geol.; (United States)

OSTI ID:7181881

Johnson, W E

One of the more active oil exploration plays in the US is the Minnelusa Formation of the Powder River basin which consists of the search for porosity traps of the Permian aged eolian sand deposits that are sandwiched among tight siltstones and dolomites and are capped with the Opeche Formation. Seismic stratigraphy has been used in this play; however, one of the most severe problems with seismic stratigraphy in the Minnelusa play is being able to distinguish between thick (or low velocity) Opeche shales and Minnelusa porosity. Corral Creek field is in an area of low velocity Opeche shales and the usual seismic data do not exhibit a porosity amplitude anomaly. Amplitude versus offset analysis adds new dimensions to seismic analysis in that it lends itself to the possibilities of including lithologic and/or pore saturant analysis by considering Poisson's ratio along with the usual seismic parameters of velocity and density. Seismic offset versus amplitude models were generated over Corral Creek field to demonstrate that there may be a detectable change in Poisson's ratio that may make it possible to detect the limits of the field. The amplitude versus offset gradient was primarily a seismic processing response to reduce the number of plots required for the amplitude with offset analysis as it was practiced. ARMA Geophysical supplied amplitude versus offset gradient sections over Corral Creek Field. The amplitude versus offset gradients were determined from the amplitude versus offset models, and a fairly good match was observed. The results of the modeling and observations show that amplitude versus offset analysis can be a helpful tool in distinguishing low-velocity Opeche shales from Minnelusa sands.

• Research Organization: Coastal Oil and Gas, Denver, CO (USA)
• OSTI ID: 7181881
• Journal Information: Mt. Geol.; (United States), Journal Name: Mt. Geol.; (United States) Vol. 25:2; ISSN MOGEA
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
ALKALINE EARTH METAL COMPOUNDS
AMPLITUDES
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATE MINERALS
CARBONATES
CONSTRAINTS
DATA ANALYSIS
DOLOMITE
EXPLORATION
FEDERAL REGION VIII
GEOLOGIC DEPOSITS
GEOLOGIC TRAPS
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MAGNESIUM COMPOUNDS
MATHEMATICAL MODELS
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OXYGEN COMPOUNDS
PETROLEUM DEPOSITS
POROSITY
POWDER RIVER BASIN
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SEISMIC SURVEYS
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USA
WYOMING