# Measurements and Observations of Fracture Height Growth

Norm Warpinski© 2011 Halliburton. All Rights Reserved. 2 

# Fracture height growth in sedimentary rocks  Clear understanding from minebacks, cores, lab tests, diagnostics, and numerical studies  Layered sedimentary sequences restrict vertical fracture growth  Reduced width in high stress & high modulus layers  Inefficient fracture growth vertically across layers and interfaces Sandstone Sandstone Mudstone & siltstone layers Mudstone & siltstone layers

Mudstone & siltstone layers Example Mesaverde section: sandstones interbedded with mudstones and stiltstones© 2011 Halliburton. All Rights Reserved. 3 

# Observations: Minebacks & Core  DOE hydraulic fracture mineback experiments at the Nevada Test Site  Government funded research into hydraulic fracture behavior  Cored fractures from the DOE Multiwell experiment & DOE/GRI M -Site  Mineback tests in coal Core in MWX test at ~7100 ft showing ~30 fracture strands in a hydraulic fracture Weak interface terminating growth in a mineback test

Weak interface

Fractures offsetting and splitting at natural fractures 2 fractures Complex mineback fracture with horizontal component & multiple strands Similar to natural fractures in core Termination at interface© 2011 Halliburton. All Rights Reserved. 4 

# Stress contrasts  Stress profile measured at DOE 

### MWX test  Most comprehensive anywhere  Large variations in stress from layer to layer  Correlates well with lithology 

###  Stress contrasts restrict vertical growth  High stress may terminate fracture  Low stress zones “trap” fracture – extensive lateral growth Source: DOE Multiwell experiment & DOE/GRI M -Site test© 2011 Halliburton. All Rights Reserved. 5 

# Offset -Well Microseismic Mapping

Treatment Well Observation Well

Typically 12 -3C Level @ 15M Observation Distance Depends on Seismic Attenuation

Perforated Interval Recorded Events • Microseismic Monitoring Is Applied Earthquake Seismology (Seismology 101)

– Based On Principles Known For Decades

– Has Been Used Since Mid - 1970’s (Hot Dry Rock)

– Primary Difference Is The Use Of A Downhole Array© 2011 Halliburton. All Rights Reserved. 6 

# Microseismic validation: DOE/GRI M -Site  M -Site diagnostics laboratory: validation of microseismic data using tiltmeters and intersection wells  Azimuth  Wellbores 

###  Height  Tiltmeters 

###  Length  Wellbores

Source: DOE/GRI M -Site test© 2011 Halliburton. All Rights Reserved. 7 

# Fracture height growth  Microseismic examples that show the extent of height growth in various formations  Haynesville  Marcellus  Eagle Ford 600 ft

900 ft SPE 125079 GMX Resources

SPE 131783,Curry et al, 2010 DUG Conference, 2010 Haynesville Example Marcellus Example Eagle Ford Example© 2011 Halliburton. All Rights Reserved. 8 

# Mapped microseismic height for Barnett shale  Top: shallowest microseism; Bottom: deepest microseism  Aquifers: USGS deepest water wells by county

Fisher: American Oil and Gas Reporter, July 2010© 2011 Halliburton. All Rights Reserved. 9 

## Mapped microseismic height for Woodford shale  Top: shallowest microseism; Bottom: deepest microseism  Aquifers: USGS deepest water wells by county

Source: Kevin Fisher, personal communication© 2011 Halliburton. All Rights Reserved. 10 

# Mapped microseismic height for Marcellus shale
 Top: shallowest microseism  Bottom: deepest microseism  Aquifers: USGS deepest water wells by county  Marcellus  Fractures far from mapped aquifers Fisher: American Oil and Gas Reporter, July 2010© 2011 Halliburton. All Rights Reserved. 11 

# Intersection with faults  Microseismicity is an excellent tool to 

### monitor what happens when a fault is intersected by a hydraulic fracture

The magnitude-distance plot shown above is an important diagnostic tool for assessing data results, effects of noise, bias, and viewability. It is also useful for determining whether fault interactions have occurred.© 2011 Halliburton. All Rights Reserved. 12 

# Tiltmeter Fracture Component Breakout versus Depth
 Tiltmeters readily identify fracture components  Horizontal  Vertical  Dipping  Combined 

###  Rapid increase in horizontal components at shallow depths preclude vertical 

### growth Source: Kevin Fisher, personal communication© 2011 Halliburton. All Rights Reserved. 13 

# Summary
 Data from thousands of fractures show:  No extensive growth vertically  Increase in horizontal components at shallower depth (little vertical growth) 

##  Sedimentary features restrict vertical fracture growth  Very inefficient growth across layers  Alternating properties and stress  Interfacial properties