What Can Microseismic Tell Us About Hydraulic Fracturing?

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1 What Can Microseismic Tell Us About Hydraulic Fracturing? Shawn Maxwell May 2015 Microseismic Geomechanics: Increased understanding; reduced risk 1

2 Outline Microseismic Introduction Microseismic in Unconventional Reservoirs Learnings after 15 years of Microseismicity Microseismic Source Mechanics Microseismic Geomechanics 2

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

4 IP (MSCFPD) Barnett Shale Development SPE77440: First Barnett Microseismic Image N 4000 E m Massive Water Fracs Horizontal Wells Microseismic Year 4

5 Reducing Carbon Emissions 5

6 Microseismic Hydraulic Fracture Applications Fracture direction Height Length Complexity 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 6

7 Project Design for Value Eng Obj Landing Point Interpretation Quality Control Cross section Target Up Accurate Processing Pre-Survey Design Quality Acquisition Cross section 7

8 Eagle Ford Example (Patel, 2013) Cross section Cross section Target Up 8

9 Project Design for Value Eng Obj Rate/Height Stages bpm Low Rate Interpretation X-section High Rate Pre-Survey Design X-section Quality Control Up Quality Acquisition Accurate Processing 9

10 Evolution of Monitoring Geometries Noise Signal Near Surface Surface Borehole Horizontal How do accuracies and sensitivities compare? How do you decide which option? SPE

11 Acquisition Footprint Downhole Array Shallow Grid 11

12 Shale Lessons: Containment 1. Depth Containment Monitor Well Treatment Well Landing Point 12

13 Environmental Concerns 13

14 Aquifer Protection 1. Spills 2. Well 3. Frac IEA 14

15 Fracture Height Growth Height (m) Piceance Jonah Horn River Cardium Montney Marcellus Barnett Woodford Eagleford Cotton Valley Spraberry Wolf Camp Bakken Haynesville Depth (m) Piceance Jonah Horn River Montney Marcellus Cardium Barnett Woodford Eagleford Cotton Valley Spraberry Wolf Camp Bakken Haynesville

16 Induced Seismicity US National Academy, 2012 No damage and rare (several sites and about 70 felt events from 3,000,000 fracs) 16

17 Shale Lessons: Heterogeneity 1. Depth Containment 2. Fracture Variability Well A Well B Monitoring Well SPE Well C 17

18 Shale Lessons: Complexity 1. Depth Containment 2. Fracture Variability 3. Fracture Complexity SPE77440 N E m Sayers

19 Shale Lessons: SRV 1. Depth Containment 2. Fracture Variability 3. Fracture Complexity 4. Stimulated Reservoir Volume Q Slurry Bank Fluid Microseismic Stage 1 - Yellow Stage 3 - Red Stress Hydraulic Stage 2 Dark Blue Stage 4 Light Blue Propped Wet Events Dry Events Uncertainty 19

20 Microseismic Interpretation Qualitative/Geometry Stages bpm Quantitative/Deformation Baig et al, 2012

21 Microseismic Mechanisms Log S/P After Rutledge et al., 2013

22 Mass/Energy Balance M 0 μ = Vol = Ad Stage 1 Stage 2 Stage 3 Stage 4 MS Volume (bbl) Frac Volume (bbl) % % % % % MS Area (ft2) Frac Area (ft2) % 0.28% % - MS Energy (J) Frac Energy (J) % % % % % Maxwell, 2014

23 Tiltmeters Hydraulic fracture induces a characteristic deformation pattern Fracture-induced surface trough Tilt/microseismic detect elastic strain waves at different frequencies Both Image the geometry and orientation of created hydraulic fracture Fracture Downhole tiltmeters In offset well

24 Generating Shear during Hydraulic Fracturing Dry Fault Activation Wet Fissure Compression Stress Shadow Shear Wet Fracture Tip Fracture Tension Wet Offset Maxwell, 2014

25 Complex Hydraulic Fracture Growth Pore Pressure Fracture Opening Fracture Shearing Synthetic Microseismic

26 Anatomy of Hydraulic Fracture DFN Wet Microseismicity Activated Fractures Primary Fractures Dry Microseismicity

27 Fracture Growth Wet Microseismicity Dry Microseismicity

28 Reservoir Drainage Production Forecast 20 Years Pressure (psi) 28

29 Conclusions Geomechanical interpretation tools key to realize the full value from microseismic 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 29