Sand-resistivity/conductivity and saturation evaluation in laminated formations with biaxial anisotropy

Patent metadata

Field	Value
Publication number	US-10422917-B2
Application number	US-201615512414-A
Country	US
Kind code	B2
Filing date	Apr 19, 2016
Priority date	Apr 19, 2016
Publication date	Sep 24, 2019
Grant date	Sep 24, 2019

Abstract

Disclosed herein are embodiments of systems, methods, and computer program products for evaluating sand-resistivity and/or sand-conductivity, as well as saturation in laminated shale-sand formations with biaxial anisotropy (BA) in resistivity. In one embodiment, the method determines sand resistivity (R sd ) of the laminated shale-sand formation directly from triaxial resistivities (R x , R y , and R z ) of the laminated shale-sand formation based on a bimodal model with BA anisotropy. In another embodiment, the method determines sand resistivity (R sd ) directly based on a bimodal model with transverse isotropy (TI) anisotropy using the triaxial resistivities, horizontal resistivity, and vertical resistivity (R x , R y , R z , R h , and R v ). In another disclosed embodiment, the above methods may be used to perform quality control on a determined sand-resistivity and saturation of a laminated shale-sand formation.

First claim

I claim:

1. A computer-implemented method for evaluating at least one of sand-resistivity and sand-conductivity, as well as saturation of a laminated shale-sand formation with biaxial anisotropy (BA), the computer-implemented method comprising:
drilling within the laminated shale-sand formation;
disposing a multi-component induction (MCI) tool within the laminated shale-sand formation, wherein the MCI tool comprises a sensor, wherein the sensor measures a property of the laminated shale-sand formation selected from the group consisting of density, neutron porosity, NMR porosity, and any combination thereof to provide a raw data,
transmitting the raw data to a system at a well site, wherein the system comprises a processor and a display module;
determining, by the processor, at least one of sand resistivity R x , R y , and R z and sand triaxial conductivities C sd x , C sd y , and C sd z of the laminated shale-sand formation based on the raw data;
determining, by the processor, at least one of sand resistivity R sd and sand-conductivity C sd of the laminated shale-sand formation based on a bimodal model with BA anisotropy using the determined at least one of sand triaxial resistivities R x , R y , and R z and sand triaxial conductivities C sd x , C sd y , and C sd z ;
determining, by the processor, a water saturation S w of the laminated shale-sand formation based on the resistivity-porosity-saturation interpretation models; and
outputting, by the display module, the at least one sand resistivity R sd and sand-conductivity C sd , and the water saturation S w of the laminated shale-sand formation; and
adjusting drilling within the laminated shale-sand formation based on the outputting.

2. The computer-implemented method according to claim 1 , wherein the water saturation S w is determined using one of a plurality of resistivity-porosity-saturation interpretation formulas.

3. The computer-implemented method according to claim 1 , wherein the laminated shale-sand formation is composed of isotropic sand and biaxially anisotropic shale.

4. The computer-implemented method according to claim 1 , wherein the laminated shale-sand formation is composed of both biaxially anisotropic (BA) sand and shale.

5. The computer-implemented method according to claim 1 , wherein at least one of sand triaxial resistivities R x , R y , and R z and sand triaxial conductivities C sd x , C sd y , and C sd z are determined using the following formulas:

⁢

1

R
x

=

(

1
-

V
lam

)

R
sd
x

+

V
lam

R
sh
x

,

⁢

(

or
⁢

⁢

C
x

=

(

1
-

V
lam

)

R
sd
x

+

V
lam

R
sh
x

=

(

1
-

V
lam

)

·

C
sd
x

+

V
lam

·

C
sh
x

,
here
,

1

R
x

=

C
x

)

⁢

1

R
y

=

(

1
-

V
lam

)

R
sd
y

Assignees

• Halliburton Energy Services Inc

Inventors

• Hou Junsheng

Classifications

• G01V11/002

  Details, e.g. power supply systems for logging instruments, transmitting or recording data, specially adapted for well logging, also if the prospecting method is irrelevant (means for transmitting well survey signals E21B47/12; signal transmission systems in general G08C; transmission in general H04B) · CPC title

• G01V3/38 Primary

  Processing data, e.g. for analysis, for interpretation, for correction · CPC title

• G01V3/28

  using induction coils · CPC title

• G01V3/32

  operating with electron or nuclear magnetic resonance · CPC title

• G01V5/10

  using neutron sources {(neutron generating tubes H05H5/00; neutron sources using isotopes G21G4/00)} · CPC title