Inversion of a vertical seismic profile by minimization of an entropy like function

Patent · Tue Jun 20 04:00:00 EDT 1989

OSTI ID:5536711

Carron, D

This patent describes a method of identifying underground geological strata from seismic traces Sk(t) recorded in a borehole at different levels {kappa} of depth Z{kappa}, wherein each trace S{kappa}(t) includes n discrete sample values sampled as a function of time t at a constant time interval {Delta}t, the method determining the series R={r/sub i/, for i=1,n} representative of seismic reflection coefficients at the interfaces formed between successive geologic strata, wherein i is an index relating to the sampling depth on a time scale at the constant interval {Delta}t, the method including the steps of: establishing the time-depth curve relating the depth Z{kappa} to the transit time T{kappa} recorded on the trace S{kappa}(t) for each level {kappa}; extracting the upgoing wavefield U{kappa}(t) and the downgoing wavefield D{kappa}(t) from the traces S{kappa}(t); and calculating U/sup mean/(t), U/sup min/(t), and U/sup max/(t) representative of mean value, minimum value, and maximum value, respectively, of the upgoing wavefield U{kappa}(t-T{kappa}), and calculating D/sup mean/(t), representative of mean value of the downgoing wavefield D{kappa}(t+T{kappa}).

• Assignee: Schlumberger Technology Corp., New York, NY
• Patent Number(s): US 4841490
• OSTI ID: 5536711
• 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
58 GEOSCIENCES
580203 -- Geophysics-- Geophysical Survey Methods-- (1980-1989)
CALCULATION METHODS
DETECTION
EXPLORATION
GEOLOGIC DEPOSITS
GEOPHYSICAL SURVEYS
MEASURING INSTRUMENTS
MINERAL RESOURCES
NATURAL GAS DEPOSITS
PETROLEUM DEPOSITS
RESOURCES
SCALING LAWS
SEISMIC ARRAYS
SEISMIC DETECTION
SEISMIC DETECTORS
SEISMIC SURVEYS
SEISMIC WAVES
SURVEYS