System and method for local attribute matching in seismic processing

Patent metadata

Field	Value
Publication number	US-9766358-B2
Application number	US-201113038234-A
Country	US
Kind code	B2
Filing date	Mar 1, 2011
Priority date	Mar 1, 2010
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

There is provided herein a new system and method of local attribute match filtering which operates in the local attribute domain via the use of complex wavelet transform technology. This approach is adaptable to address various noise types in seismic data and, more particularly, is well suited to reduce the noise in geophone data as long as an associated hydrophone signal is relatively noise-free.

First claim

What is claimed is:

1. A method of geophysical exploration, wherein is provided an ocean bottom survey containing a plurality of hydrophone component seismic traces and a plurality of geophone component seismic traces, the method comprising the steps of:
a. accessing said ocean bottom survey;
b. reading at least sixteen of said plurality of hydrophone component seismic traces;
c. reading at least sixteen of said plurality of geophone component seismic traces;
d. calculating a forward complex wavelet transform on said read at least sixteen hydrophone component seismic traces, thereby forming a complex wavelet transform pressure dataset;
e. calculating a forward complex wavelet transform on said read at least sixteen geophone component seismic traces, thereby forming a complex wavelet transform geophone dataset;
f. matching, including a local attribute matching, said complex wavelet transform geophone dataset to said complex wavelet transform hydrophone dataset to produce a matched complex wavelet transform dataset by calculating the quantity
Z ′( t,x,y,s,o,ri )= Z ( t,x,y,s,o,ri )*| P ( t,x,y,s,o,ri )|*Envp( t,x,y,s,o ),

where Envp(t,x,y,s,o) is an envelope scaling factor determined by,

Envp
⁡

(

t
,
x
,
y
,
s
,
o

)

=

1

Z
⁡

(

t
,
x
,
y
,
s
,
o
,
real

)

2

+

Z
⁡

(

t
,
x
,
y
,
s
,
o
,
imaginary

)

2

,

and where
Z′(t,x,y,s,o,ri) is said matched complex wavelet transform dataset,
Z(t,x,y,s,o,ri) is said complex wavelet transform Z dataset,
P (t,x,y,s,o,ri) said complex wavelet transform P dataset,
t is time,
x is an X coordinate vector associated with said at least sixteen geophone component traces,
y is a Y coordinate vector associated with said at least sixteen geophone component traces,
o is an orientation vector,
s is a scale vector, and,
ri is a vector that contains either a real component or an imaginary component depending on the context;

g. calculating an inverse complex wavelet transform on said complex wavelet transform dataset to produce at least sixteen matched seismic traces;
h. obtaining a matched seismic image using the at least sixteen matched seismic traces, the matched seismic image having a signal-to-noise ratio that is greater than a signal-to-noise ratio of a second seismic image obtained using said at least sixteen of said plurality of geophone component seismic traces, wherein the matched seismic image is representative of a subsurface of the earth and,
i. using said at least sixteen matched seismic traces to locate a drilling site in the subsurface of the earth for seismic exploration for subsurface hydrocarbons.

2. The method of geophysical exploration according to claim 1 , wherein said forward complex wavelet transform comprises a forward 3D complex wavelet transform and said inverse complex wavelet transform comprises an inverse 3D complex wavelet transform.

3. The method of geophysical exploration according to claim 1 , wherein said orientation vector has six elements comprising 75 degrees, 45 degrees, 15 degrees, −75 degrees, −45 degrees, and −15 degrees.

4. A method of geophysical exploration within a predetermined volume of the earth containing subsurface structural and stratigraphic features conducive to the generation, migration, accumulation, or presence of hydrocarbons, wherein is provided two sets of seismic traces, one a set of hydrophone traces and the other a set of geophone traces seismic surveys each having a plurality of seismic traces associated therewith, the method comprising the steps of:
a. determining a selected number of input traces to read;
b. accessing a first of said two sets of seismic traces;
c. reading at least said selected number of input traces from said first set of seismic traces;
d. accessing a second of said two sets of seismic traces;
e. reading at least said selected number of input traces from said second set of seismic traces;
f. calculating a forward complex wavelet transform on said read input traces from said first set of seismic traces, thereby forming a first complex wavelet transform dataset;
g. calculating a forward complex wavelet transform on said read input traces from said second set of seismic traces survey, thereby forming a second complex wavelet transform dataset;
h. matching said first complex wavelet transform dataset to said second complex wavelet transform dataset to produce a matched complex wavelet transform dataset, the matching including a local attribute matching, by calculating the quantity
Z ′( t,x,y,s,o,ri )= Z ( t,x,y,s,o,ri )*| P ( t,x,y,s,o,ri )|*Envp( t,x,y,s,o ),

where Envp(t,x,y,s,o) is an envelope scaling factor determined by,

Envp
⁡

(

t
,
x
,
y
,
s
,
o

)

=

1

Z
⁡

(

t
,
x
,
y
,

Assignees

• Yu Zhou
• Ahmed Imtiaz
• Bp Corp North America Inc

Inventors

• Yu Zhou
• Ahmed Imtiaz

Classifications

• G01V1/368 Primary

  Inverse filtering · CPC title

• G01V2210/32

  Noise reduction · CPC title