Microseismic Geomechanics: Increased understanding; reduced risk

What Can Microseismic Tell Us About

Hydraulic Fracturing?

Shawn Maxwell

May 2015

1

Outline

•Microseismic Introduction

•Microseismic in Unconventional Reservoirs

•Learnings after 15 years of Microseismicity

•Microseismic Source Mechanics

•Microseismic Geomechanics

2

Hydraulic Fracturing: Where Does It All Go?Fracture Complexity & Natural Fractures

Natural FracturesHydraulic

Fractures

Natural FracturesHydraulic

Fractures

Barnett Shale Development

4

Year1980 1990 2000

10000

8000

6000

4000

2000

0

IP (

MS

CF

PD

)

Massive Water Fracs

Horizontal Wells

Microseismic

0 100 m

N

E

SPE77440:

2000 First Barnett Microseismic Image

Reducing Carbon Emissions

5

Microseismic Hydraulic Fracture Applications

✔ Fracture direction

✔Height

✔ Length

✔Complexity

6

Optimize Stimulation Design

• height growth

• injection rate and volume

• fluid type, additives, and diverters

• proppant placement

Validate Completion Design

• completion types and designs

• stage isolation

• stage sequencing

• refracturing

Refine Well Plan

• well orientation

• landing point

• well integrity

Improve Reservoir Management

• well spacing

• well placement

• induced seismicity and fault activation

• reservoir characterization

• production optimization

Project Design for Value

7

Eng Obj

Landing Point

Accurate

Processing

Quality

Acquisition

Pre-Survey

Design

Quality

Control

Interpretation

Up

Target

Cross section Cross section

Eagle Ford Example (Patel, 2013)

8

Up

Target

Cross section Cross section

Project Design for Value

9

Eng Obj

Rate/Height

Accurate

Processing

Quality

Acquisition

Pre-Survey

Design

Quality

Control

InterpretationX-section X-section

Up

LowRate

HighRate

Stages 1-2

120 bpm

Evolution of Monitoring Geometries

10

Noise Signal

Near

Surface

Borehole

Surface

Horizontal How do accuracies and sensitivities compare?How do you decide which option?

SPE159670

Acquisition Footprint

11

Downhole Array Shallow Grid

Shale Lessons: Containment

12

1. Depth Containment

Landing Point

Treatment Well

Monitor

Well

Environmental Concerns

13

Aquifer Protection

14

IEA

1. Spills

2. Well

3. Frac

Fracture Height Growth

15

De

pth

(m

)

0

1000

2000

3000

4000

Marc

ellu

sPic

ea

nce

Jo

nah

Ho

rn R

iver

Wo

od

ford

Barn

ett

Sp

rab

err

y

Wo

lf C

am

p

Bakken

Hayn

esville

Co

tto

n V

alley

Mo

ntn

ey

Card

ium

Eag

lefo

rd

He

igh

t (m

)

-500

-400

-300

-200

-100

0

100

200

300

400

500

-500

-400

-300

-200

-100

0

100

200

300

400

500

Ma

rce

llu

s

Pic

ean

ce

Jo

na

h

Ho

rn R

ive

r

Wo

od

ford

Barn

ett

Sp

rab

err

y

Wo

lf C

am

p

Bakken

Hayn

es

ville

Co

tto

n V

alle

y

Mo

ntn

ey

Card

ium

Ea

gle

ford

16

US National Academy, 2012

No damage and rare

(several sites and about 70 felt events from 3,000,000 fracs)

Induced Seismicity

Shale Lessons: Heterogeneity

17

1. Depth Containment

2. Fracture VariabilityWell A

Well B

Well C

Monitoring

Well

Well AWell B

Well C

Monitoring

Well

SPE144207

Shale Lessons: Complexity

18

0 100 m

N

E

1. Depth Containment

2. Fracture Variability

3. Fracture Complexity

SPE77440

Sayers 2010

Shale Lessons: SRV

19

1. Depth Containment

2. Fracture Variability

3. Fracture Complexity

4. Stimulated Reservoir Volume

Stage 1 - Yellow

Stage 2 –Dark Blue

Stage 3 - Red

Stage 4 – Light Blue

Slurry

Fluid

Bank

Q

Microseismic

Dry Events

Hydraulic

Propped

Wet Events

Stress

Uncertainty

Microseismic Interpretation

Qualitative/Geometry

Quantitative/Deformation

Baig et al, 2012

Stages 1-2

120 bpm

Microseismic Mechanisms

1.5

1.0

0.5

0

-0.5

Log

S/P

After Rutledge et al., 2013

Mass/Energy Balance

Stage 1 Stage 2 Stage 3 Stage 4

MS Volume (bbl) 0.82 0.15 0.075 0.30

Frac Volume (bbl) 25300 25300 25300 25300

% 0.0033% 0.00059% 0.00030% 0.0012%

MS Area (ft2) 19375 4018 3533 9040

Frac Area (ft2) 7000000 - 6200000 -

% 0.28% - 0.057% -

MS Energy (J) 62500 11300 5700 22950

Frac Energy (J) 149040000000 149040000000 149040000000 149040000000

% 0.0042% 0.00076% 0.00038% 0.0015%

𝑀0𝜇 = 𝑉𝑜𝑙 = 𝐴𝑑

Maxwell, 2014

Tiltmeters

Hydraulic fracture

induces a characteristic

deformation pattern

Tilt/microseismic detect

elastic strain waves at

different frequencies

Both Image the geometry

and orientation of created

hydraulic fracture Fracture

Fracture-inducedsurface trough

Downhole tiltmetersIn offset well

Generating Shear during Hydraulic Fracturing

“Dry” Fault Activation “Wet”

Fissure

“Wet”

Fracture Tip “Wet”

Offset

Tension

Shear

Compression

Fracture

Stress “Shadow”

Maxwell, 2014

Complex Hydraulic Fracture Growth

Pore Pressure Fracture Opening

Fracture Shearing Synthetic Microseismic

Anatomy of Hydraulic Fracture

DFN

Primary Fractures

Activated Fractures

Wet Microseismicity

Dry Microseismicity

Fracture Growth

Wet Microseismicity Dry Microseismicity

Reservoir Drainage

28

Pressu

re (psi)

Production Forecast 20 Years

Conclusions

29

•Microseismic key technology to image hydraulic fractures

•Microseismic demonstrated complex fracture networks

•Microseismic volume oversimplification

•Microseismic calibration of complex geomechanical fracture

model

Enables reservoir simulation of well performance

Estimates drainage for well spacing

Geomechanical interpretation tools key to

realize the full value from microseismic