Propagation of Hydraulic Fractures in the Subsurface: A Multi-basin study

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1 Propagation of Hydraulic Fractures in the Subsurface: A Multi-basin study GWPC: UIC Summit Jan 24, 2012 March 17, 1949 Kevin Fisher Executive VP Flotek Industries

2 What Do Fractures Really Look Like?

3 Downhole Microseismic Mapping Snap, crackle, and pop of the fracture Microseismic Monitoring Is Applied Earthquake Seismology Based On Principles Known For Decades Has Been Used Since Mid-1970 s Treatment well Observation distance Depends on seismic attenuation Observation well Recorded events Perforated interval

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5 FracMap from Barnett Variable containment Usually Good Containment Confined by high stress layers Sometimes Upward or Downward growth Poor Confining Layers Faulting SPE 95568

6 BARNETT FRACS TO SCALE

7 Mapped microseismic height for Barnett shale Top: shallowest microseism; Bottom: deepest microseism Aquifers: USGS cd&submitted_form=introduction Smallest height growth at shallow depths Large spikes are likely fault interactions

8 Fracture height growth Variable containment in shales Containment (e.g., Eagle Ford & Barnett) Bounded by carbonates Upward growth (e.g., Marcellus & Haynesville Relatively continuous shale Faulting Common and bi-directional SPE GMX Resources 600 ft Haynesville Example Eagle Ford Example Marcellus Example 900 ft DUG Conference, 2010 SPE ,Curry et al, 2010

9 Mapped microseismic height for Woodford shale Smallest height growth at shallow depths

10 Mapped microseismic height for Marcellus shale Smallest height growth at shallow depths

11 Mapped microseismic height for Eagle Ford shale Eagle Ford (TX) Mapped Fracture Treatments/TVD Smallest height growth at shallow depths Depth (ft) Frac stages (sorted on perf midpoint)

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13 Tiltmeter Fracture Complexity vs Depth

14 Observations: Minebacks & Core Hydraulic fractures are complicated features What we see: Multiple strands Offsets at discontinuities Kinking, branching & turning Core in MWX test at ~7100 ft showing ~30 fracture strands in a hydraulic fracture Weak interface Fractures offsetting and splitting at natural fractures 2 fractures Complex mineback fracture with horizontal component & multiple strands Weak interface terminating growth in a mineback test Source: DOE mineback, Multiwell Experiment & Slant Hole Completion Tests

15 Fracture height growth what we know Exact fracture height difficult to predict Layer properties; interface properties; stresses General understanding Layered sedimentary sequences restrict vertical growth Reduced width in high stress & high modulus layers Termination, blunting, kinking, bifurcating, offsetting & splitting at interfaces Loss of fluid into permeable zones Mudstone & siltstone layers Sandstone Mudstone & siltstone layers Sandstone Mudstone & siltstone layers

16 Summary Decades of study and monitoring of thousands of fracture treatments have demonstrated: Fracture treatments in shales do not grow into aquifers Microseismic data Fracture growth vertically is inhibited by layering & interfaces Mineback, laboratory, numerical, and field studies Fracture growth in the near-surface region is limited by horizontal components Tiltmeter data, stress measurements Faults can influence fracture growth, but do not provide pathways for fracture fluid to reach the surface From a physics and rock mechanics perspective, hydraulic fracturing is safe

17 OK Fracs Are Safe; What About Spills? Green Chemicals The Dose makes the Poison - Paracelsus, 16 th Century Chemist Any substance can be bad to human health in the right dosage. Examples: Water and Vitamin C can kill humans if concentrations are high enough in the stomach or blood stream. Acrylamide (a common oilfield chemical) is contained in over 750 common foods including ketchup, olives, breakfast cereal and coffee. Acrylamide is also a carcinogen Food Grade: Food grade is simply a way to communicate with the public in terms they understand. It doesn t mean that it cannot cause harm to human s. Food grade concept may not consider dosage Many may not understand this But ALL understand this 17

18 CnF Ingredients Are in Common Household Items CnF Composition Surfactants Dish Soap Shampoo CnF Solvent Fruit Juices Hand Cleaners Alcohols Vanilla Flavoring Mouthwash Water Tap Water Bottled Water

19 5 Area Composite of CnF Wells vs Offsets Flotek / CESI CnF 369 Well Study Histogram of Normalized 30 Day Cum Equivalent Recovery CnF P50 Nrmd 30D Cum Eqv = mcf Eqv/K# (167 wells) non-cnf P50 Nrmd 30D Cum Eqv = mcf Eqv/K# (202 wells) Nrmd 30 Day Eqv Recovery (mcf Eqv/K#) t % 25% 50% 75% 100% Cumulative Frequency (% less than)

20 CESI GREEN Initiative Summary Many definitions of Green emerging (3 rd parties, governments and oilfield companies) CESI s goal is to continue to develop greener oilfield chemicals. CESI Green Check is based on objective criteria: North Sea, Federal Regulations, Sustainability. 20

21 Thank You