The

Revealed with Full Azimuth 3D Multi-

Component Seismic Data.

By

Tony Rebec, Jim Gaiser, Alvaro Chaveste and Richard Vern,

Geokinetics, Houston.

- Introduction to the Marcellus Shale/data

- Geophysical Strategy

- Vertical Calibration & Resolution

- Spatial Resolution & Geometric Attributes

- Anisotropic/Rock Property Attributes

- Conclusions

The

Revealed with Full Azimuth 3D Multi-Component

Seismic Data.

United States Shale Gas Plays

500Tcf

Generalized Geologic Cross-Section of

Catskill Delta Magna Facies

+ Ordovician Utica Shale

Marcellus Shale – Depth & Isopach Maps

Depth Isopach

Bradford-Mehoopany 3D Pennsylvania

N

Net Feet of Organic Rich Shale

in the Marcellus Formation, Pennsylvania

Bradford County

Time Slice from Bradford 3D

Phase I & Mehoopany

Seismic Survey

3D/3C

Anisotropy

study 3D

Elevations

from

Acquisition

Zeroing in on the Marcellus Shale Play in Pennsylvania with High Fidelity 3D Full

Azimuth Surface Seismic Data Including Simultaneous Multi-Component 3D data for

Calibration and Identification of Fracture Sweet Spots. (Data not vertically corrected

for velocity differentials)

P-Wave Production P-Wave Component Shear-Wave Shear-Wave

Fast Component Slow Component

AJR

3D Data Sets

Geophysical Strategy

Maximize information obtained from seismic

(appropriate Acquisition/Processing) and

optimize its resolution:

1. Structural and stratigraphic framework

Trace and geometric attributes

2. Fracture characterization

Anisotropic attributes

3. Matrix (reservoir and rock) properties

Inversion attributes

Vertical Calibration/Resolution

Inline & Crossline

Tully

Marcellus

Syracuse Salt

Onondaga

Cut-a-way Seismic Cube

4388’

4496’

6076’

6228’

6249’

6382’

152’

133’

CHERRY VALLEY

28’

Marcellus Shale Vertical Resolution Sonic

Vertical Resolution

Seismic

Thin-Bed Reflectivity re Tanner

*

*

Spatial Resolution/Geometric Attributes

Onondaga

Amp

Base Marcellus Shale - twt

Top Marcellus Shale – seismic amplitude

J1 & J2 Fracture Sets in Marcellus

J1

J2

J1 J1

J2 J2

J1 & J2 Fracture Sets in Marcellus

Natural gas chimneys in black shale

showing cross fold J2 joints

Geology Seismic

Energy Ratio

Unbiased accurate faulting

time slice

Landmark GeoProbe

Co-rendered

seismic & semblance

Positive Curvature

Bradford & Mehoopany 3D

Seismic Attributes

Unbiased accurate structural deformation – positive flexures (highs)

Positive Curvature – time slice

Positive Curvature

time slice

High fidelity

Normal

Unbiased accurate structural deformation – negative flexures (lows)

time slice

Negative Curvature – time slice

1120 ms - Marcellus

Negative Curvature

time slice

High spatial fidelity

normal

Horizon TWT Horizon Textural Rendering Co-rendered

Textural Rendering

Anisotropic Attributes

Reservoir and Rock Properties

Vp, Vs, ρ

Amplitude

P-impedance

S-impedance

Poisson’s ratio

Young’s Modulus

LambdaRho

MuRho

Anisotropy

Lithology

Composition

Porosity

Fluid content

TOC content

Brittleness

Fractures

Pore pressure

Stress

etc.

Anisotropic/Rock Property Attributes

Anisotropy

1. Elliptical Inversion using P-wave Interval Velocities

2. Time differentials from Shear waves (3 comp)

Rock Properties

1. Lambda*Rho Mu *Rho

Density and Orientation of Micro-fractures

Physical Basis

Velocities dependence on fractures’ direction. <-

Cra

ck

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

Difference between fast and slow velocities (anisotropy) is a measure of

fracture density

- Azimuth

VMAX

VMIN

(VMAX-VMIN)/VMAX

e - Error

Elliptical Inversion (EI) to estimate anisotropy

Time Slice: 680 ms

pstm stk Interval Velocities

All Azimuths

Hand-Picked

Interval Velocities

Azimuth 1

AutoVels

Interval Velocities

Azimuth 2

AutoVels

Interval Velocities

Azimuth 3

AutoVels

Interval Velocities

Azimuth 4

AutoVels

Automatic Velocity Picking

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

Low High

Better resolution velocity field

Velocity field for azimuthal NMO correction

Elliptical Inversion

Inline

Azimuth co-rendered with Stack

Anisotropy Azimuth (degrees)

Marcellus Marcellus

Elliptical Inversion Anisotropy Comparison

Sectored

From Interval Velocities

Un-sectored

From RMS Velocities

Stack

Elliptical Inversion Azimuth and Anisotropy

Top Marcellus + 40 msec

Anisotropy Azimuth (deg)

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

Elliptical Attributes

Un-sectored Elliptical Inversion

Elliptical Inversion Azimuth and Anisotropy

Top Marcellus + 40 msec

Anisotropy Azimuth (deg)

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

<-C

rack

Orien

tatio

n

Velocity Ellipse

A = Semi-major axis

B = Semi-minor axis

= Azimuth

A

B

N

Elliptical Attributes

Sectored Elliptical Inversion

Co-rendered Azimuth/Anisotropy - Positive Curvature

Azimuth

Anisotropy

J1 – “Maintains ENE orientation regardless

of location relative to the oroclinal bends”

J2 - “In the Valley and Ridge, J2 is found

normal to fold axes…”

Engelder, T. “Structural geology of the Marcellus and

other Devonian gas shales”

Anisotropic/Rock Property Attributes

Anisotropy

1. Elliptical Inversion using P-wave Interval Velocities

2. Time differentials from Shear waves (3 comp)

Rock Properties

1. Lambda*Rho Mu *Rho

PS2 to PS1 Registration

PS2 to PS1 Registration

Time to Top Salt

PS2 to PS1 Registration

Cumulative Time Differences PS1 Stack

PS2 to PS1 Registration

Absolute

Interval Anisotropy PS1 Stack

Fracture Characterization

• Geometric attributes for subtle

changes in regional trends – fold,

fault, fracture

• Anisotropic attributes through

elliptical inversion

Fracture location, azimuth

and intensity

Multiple, complementary

methods

Converted wave solutions

• Methods to constrain and

calibrate. Azimuth (deg) Anisotropy (%)

Co-rendered Positive Curvature

with Anisotropy

Anisotropic/Rock Property Attributes

Anisotropy

1. Elliptical Inversion using P-wave Interval Velocities

2. Time differentials from Shear waves (3 comp)

Rock Properties

1. Lambda*Rho Mu *Rho

Reservoir and Rock Properties

Vp, Vs, ρ

Amplitude

P-impedance

S-impedance

Poisson’s ratio

Young’s Modulus

LambdaRho

MuRho

Anisotropy

Lithology

Composition

Porosity

Fluid content

TOC content

Brittleness

Fractures

Pore pressure

Stress

etc.

Reservoir and Rock Properties

P-wave Impedance S-wave Impedance

Lambda*Rho (lr) Mu*Rho (mr)

Density

Lambda*Rho - Mu*Rho

Cross-plot

4400 to 8000 ft

lr

mr

Lambda*Rho (lr)

Reservoir and Rock Properties

Log Crossplot

Seismic Crossplot

Cross-plot from Seismic

Density Density

Lambda*Rho (lr) Mu*Rho (mr)

Low density ~ high TOC

Conclusions

Using Seismic Effectively in the Marcellus Unconventional

Play

• Begins with acquiring and processing high resolution image

• Provides structural and stratigraphic framework – Well placement, hazard avoidance and geosteering

– Reservoir architecture and delineation

– Geometric attributes may predict stress/ fracture zones

• Fracture characterization – Complementary methods

– Fracture location, orientation, and intensity

• Reservoir and rock property determination – Matrix quality

– Geomechanical properties

– Fluid indicators

Q & A

With Tony Rebec, Geokinetics

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