Method of enhancing common depth point seismic data

Patent · Tue May 13 04:00:00 EDT 1980

OSTI ID:5865990

Johnson, J P; Lunsford, D R; Parrack, A L

A method is disclosed for enhancing a ''gather'' formed of a plurality of unmoved out common depth point (Cdp) data traces. The gather is formed of a plurality of seismic traces arranged in a display in which time varies along the horizontal axis and distance between source and detector (Range) varies along the vertical axis. The gather is incrementally processed by cross correlating trace segments within a defined area or search window. To this end, the center trace within the window is selected as a reference trace which is multiplied by a taper function and cross correlated with the other traces in the window to provide a coherent trace and a separate noise trace, both of which are produced in the output. The window is shifted on the gather and the procedure is repeated until every trace has been processed. In the cross correlation technique, the trace segments in the window are examined along a derived hyperbolic curve. To this end, the traces are time shifted to the positions producing optimum alignment with the reference trace along the hyperbolic curve and are then summed with the reference trace segment along the curve and averaged. The resultant coherent trace is multiplied by a taper function and reproduced in the output in time alignment with the reference trace. A separate noise trace is also obtained by subtracting the coherent trace from the reference trace. The cross correlation proceeds through the entire gather at half window increments until a new gather is formed. Also disclosed is a method for deriving the hyperbolic curves connecting common events at the center of each window.

• Assignee: Texaco Inc
• Patent Number(s): US 4203161
• OSTI ID: 5865990
• 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
580201 -- Geophysics-- Seismology & Tectonics-- (1980-1989)
CORRELATIONS
DATA ANALYSIS
DIGITAL SYSTEMS
DISTANCE
GEOPHYSICAL SURVEYS
ISOTOPE APPLICATIONS
MEASURING INSTRUMENTS
NATURAL GAS WELLS
OIL WELLS
SEISMIC ARRAYS
SEISMIC DETECTORS
SEISMIC SOURCES
SEISMIC SURVEYS
SURVEYS
TIME MEASUREMENT
TRACER TECHNIQUES
WELL LOGGING
WELLS