Method for interpreting seismic records to yield indications of gas/oil in an earth formation such as a sandstone, limestone, or dolostone
The present invention indicates that acoustic characteristics associated with gas/oil-containing strata such as a sandstone, limestone or dolostone, including reflectivity coefficients can be normalized (and favorably compared) with similar characteristics calculated and displayed by means of a machineimplemented data processing method in which well logging and geologic data are fed thereto to calculate such characteristics without the need for shear-wave velocities. In more detail, in accordance with the invention brine-saturated bulk and shear moduli, (i.e., kw* and gw*) of a sandstone, limestone or dolostone can be predicted as a function of, say, brine-saturated p-wave modulus (pw*) alone (Independent of shearwave velocity). In that way, resulting acoustic values including seismic velocities and amplitudes (also, reflectivities) as a function of a saturation operator can ultimately be provided. Such values, when compared to actual field-generated characteristics, are surprisingly accurate predictors of the amount of gas/oil saturation in the zone of interest. The method has particular accuracy in designating gas zones within formations of interest due to use of the complete Benedict-Webb-Rubin non-ideal gas law in pseudo-reduced form, as cited in Journal of Current Petroleum Technology, Vol. 22, pp. 889-895.
- Assignee:
- Chevron Research Co
- Patent Number(s):
- US 4375090
- OSTI ID:
- 6292588
- Resource Relation:
- Patent File Date: Filed date 9 Oct 1979; Other Information: PAT-APPL-083189
- Country of Publication:
- United States
- Language:
- English
Similar Records
Method for interpreting well log records to yield indications of gas/oil in an earth formation such as a sandstone, limestone, or dolostone
Method for interpreting seismic records to yield indications of gas/oil in an earth formation
Related Subjects
03 NATURAL GAS
47 OTHER INSTRUMENTATION
NATURAL GAS DEPOSITS
SEISMIC SURVEYS
PETROLEUM DEPOSITS
WELL LOGGING EQUIPMENT
ACOUSTIC MEASUREMENTS
DOLOMITE
LIMESTONE
NATURAL GAS WELLS
OIL WELLS
SANDSTONES
ALKALINE EARTH METAL COMPOUNDS
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATE MINERALS
CARBONATE ROCKS
CARBONATES
EQUIPMENT
GEOLOGIC DEPOSITS
GEOPHYSICAL SURVEYS
MAGNESIUM CARBONATES
MAGNESIUM COMPOUNDS
MINERAL RESOURCES
MINERALS
OXYGEN COMPOUNDS
RESOURCES
ROCKS
SEDIMENTARY ROCKS
SURVEYS
WELLS
020200* - Petroleum- Reserves
Geology
& Exploration
030200 - Natural Gas- Reserves
Geology
& Exploration
440400 - Well Logging Instrumentation