Horizontal Fracturing in Shale Plays. Matt McKeon

Transcription

1 Horizontal Fracturing in Shale Plays Matt McKeon

2 Shortening the learning curve Historically: a trial-and-error process Data acquisition USA analog fields can speed up evaluation and development Quantify Construct Complete Analyze Gas Rate Sim Gas Rate Oil Rate Oil rate Sim 2

3 Recent plays: fracture stimulations are evolving WaterFracs 8-10 Stages BPM 1.5 MM lbs prop 100 Mesh, 40/70 1 ppg Max 7 MM Gal 40,000 HHP /Stage Hybrid/Conv Stages BPM 3-4 MM lbs prop (total) 30/60, 20/ ppg 4 MM Gal 25,000 HHP /Stage Eagle Ford 3

4 Even Barnett stimulation is still changing Barnett Shale Completion Roadmap Barnett Shale Completion Roadmap Avg. BP M bbl/stag e s p an ft. BPM Treatment span sks/stag ge bbl/stage sks/stage year Year 4

5 Shale Gas Development Process Workflow Data Acquisition 5 5

6 Shale parameters to enhance commercial production Gas content : > 100 scf/ton Thermal maturity (Ro) : 0.7 to 2.5+ range; 1.2 typical Permeability : greater than 100 nanodarcies Porosity : > 4% Pressure : above normal TOC : > 2% Water saturation : < 45% Well bounded & thick zone : > 100 ft Moderate clay content : < 40% Well bounded : i.e. good frac barriers Brittle shale (fracability) : i.e. low Poisson s & high YM Natural fractures : moderate presence 6

7 Shale Prospect Woodford Barnett Haynesville Marcellus Eagleford Bakken Porosity (%) % ~1.5 6 (Avg. ~3.8) 8-15% 3 8% 3-15% 2-12 % TVD (ft) 4,100 4,300 6,000 14,000 5,400 9,500 10,500 14,000 4,500-8,500 5,000-13,000 8,000-11,000 Thickness (ft) ft & ft BHT ( F) º F TOC (%) % 4-8% 2-5% 3-10% 0.5-9% Upper-11%-40% Lower=8%-21% Press Grad (psi/ft) Frac Grad (psi/ft) ~ > Avg Perm (μd) < Sw (%) 27 33% <35 no free water < Lithology (%) Silica rich Silica- Chert 30-60% Silica rich v/v Shale is soft (ductile) Calcite rich-in areas silica rich (in areas) organic rich High clay mineral fraction Variable formation properties Illite clay-dominated Quartz/Plagioclase/ Feldspar Carbonates Siderite/Pyrite ~3-5% carbon content High Illite-dominate clays Looks like poker chips High in Calcites Silty, sandy, dolomite grading to laminated shaly interval. Some natural fractures. Below is Sanish YM (x10 6 psi) Upper/Lower= 2-4 Middle=4-6 PR (%) Upper/Lower= Middle= Quartz, wt % Plagioclase feldspar, wt % Calcite, wt % Smectite,wt % < Illite, wt % Kaolinite wt % < Chlorite, wt % Ro (Maturity of Shale) Analog Analysis

8 U.S. shale play: choose stimulation Frac System Barnett Woodford Haynesville Eagle Ford Marcellus Waterfrac (WF) WF /Linear Gel WF, Hybrid, & X-Linked Hybrid WF and Hybrid TVD 5,400-9,500 ft. 6,000-14,000 ft. 10,500-14,000 5,000-13,000 ft. 4,500-8,500 ft. Lateral Length 4,000 ft. 4,000 ft. 4,500 ft. 4,000 ft. 3,000-5,000 ft. Stages Fluid Volume 5.0 MM (8 stg) 6.5 MM (10 stg) 5.0 MM (10 stg) 4.0 MM (12 stg) 5.0 MM (12 stg) Proppant Vol. 3.5 MM lbs. 4.5 MM lbs 2.5 MM lbs 3.5 MM lbs 5.5 MM lbs Completion Type Cemented Csg. Cemented Csg. Cemented Csg. Cemented Csg. Cemented Csg. (1)P&P (1) P&P (1) P&P (1) P&P (1) P&P (2)BASS (2) BASS (2) BASS (2) BASS (2) BASS (3)Hydrajet (3) Hydrajet (3) Hydrajet (3) Hydrajet (3) Hydrajet Span/Stage 400 ft. 400 ft. 300 ft ft ft. Clusters/Length ft. 2-4ft. 1-2ft. 1-2ft. 2-4ft. Analog Analysis

9 Shale Analysis Log Where would you perforate? What is the TOC and gas content? Mineralology Lithology Brittle or Ductile? Kerogen Content Will it frac and what is the relative fracture width and barriers? Reservoir Properties Natural What is the shale Fractures? in place? Unconfined Compressive volumetric gas Strength What is the shale porosity and permeability? Where is the organic rich shale? Where are the zones of highest kerogen content Shale Type Frac Ease TOC Hydrocarbon Content SPE

10 Shale fracturing simulation Designed for complex fracturing Couple available data with microseismic to optimize fluid system and frac design Recalibrate model based on post job analyses and regional variations

11 OBJECTIVE Maximize stimulated reservoir volume (SRV) 11

12 Shale fracture characteristics To create complexity you must have: 1. Pre-existing natural fissures 2. Low differential horizontal stresses (net pressure > σ m m) 3. Brittleness Ductile Brittle Tight Gas Sands Haynesville Eagleford Woodford Bakken Marcellus Barnett 12

13 Shale Completion Strategy: Based on Formation Brittleness & Liquid Production SPE Fracture Fracture Width Brittleness Fluid System Geometry Closure Profile 70% Slick Water 60% Slick Water 50% Hybrid 40% Hybrid 30% X-Linked 20% X-Linked 10% X-Linked Proppant Fluid Proppant Liquid Brittleness Concentration Volume Volume Production 70% Low High Low Low 60% 50% 40% 30% 20% 10% High Low High High 13

14 Shale fluid decisions Shale Type Frac Type Fluid Type & Prop ppg Brittle & low clay Brittle & high clay Ductile & low clay Ductile & high clay Complex network No embedment Complex network Some embedment Less complex Moderate embedment Bi-Wing High embedment Water 0-2% KCL ppg Water 2-7% KCL Linear gel ppg Water 0-2% KCL Linear gel. X-Link Tail ppg Linear Gel 2-7% KCL X-Link ppg 14 14

15 Lateral design, stage intervals & well spacing Lateral Drilled in direction on minimum horizontal stress for transverse fracturing Greater than 90 degree deviation is common practice Stay in best portion of the reservoir while drilling Longer laterals yield more production to a point cost considerations Stage intervals Number of intervals varies by shale play most 300 to 400 ft Most often, shorter intervals increase SRV and production more cost Couple with perforation interval distribution for optimum SRV from frac Well Spacing 15

16 Perforation clusters Typically evenly spaced along stage interval good rock or bad Number of clusters varies by shale play, less perm & complexity closer Number of perfs affect limited entry diversion The more clusters placed, the less contribute to production Placement in better rock (fracs, brittle) may enhance SRV and production 16

17 Shale Fracture Characteristics Definition of Brittleness from Rock Mechanics SPE Haynesville Marcellus Eagle Ford Woodford o d Barnett BRIT

18 Barnett example pump schedule 4000 ft laterals Span = ± 400 ft Stage size = 15,500 bbl/stage Prop volume = 4300 sks/stage Number of stages 6 8 Prop type: 60% 100 mesh, 40% 40/70 Rate = 70 BPM End sand conc = ppg 1.5 Treating pressure = 4000 psi SRV (ft 3 )= 4/3*π*ABC A=networkA width B=frac length C=height/2 gal ppg prop lbs rate time pad slurry mesh slurry mesh slurry mesh slurry mesh slurry mesh slurry / slurry / flush % 100 mesh 56.34% total lbs lbs % 40/ % total time hr 3.38 hr % pad 15.38% avg ppg 0.66 ppg lbs 100 mesh lbs lbs 40/ lbs total volume gal 15,476 BBL

19 Formation hardness and proppant embedment BHN # Woodford Marcellus Floyd Eagle Ford Haynesville Bossier Barnett CV Lime Ohio SS Coal 19

20 Haynesville - example pump schedule 6 perforation cluster - 72 BPM Stage Fluid Volume Prop Prop Concent Rate/cluster 1 Treated Water Guar (R11) mesh lb 3 Guar (R11) mesh lb 4 Guar (R11) mesh lb 5 HYBOR G (R27) HYBOR G (R27) Main Proppant lb 7 HYBOR G (R27) Main Proppant lb 8 HYBOR G (R27) Main Proppant lb 9 HYBOR G (R27) Main Proppant lb 10 HYBOR G (R27) Main Proppant lb 11 Guar (R11) flush 12 Total fluid volume per stage gal Total proppant per stage lb 100 mesh Pump Time per Stage 102 minutes lb Main Proppant 12 Stages per Well Main Proppant = 40/70 PowerProp or Volume / Well = 3,714,000 gal 40/80 HydroProp or 100 mesh / Well = 570,000 lb % pad = 37% 30/60 CarboProp or Main Proppant / Well = 4,266,000 lb 30/50 InterProp or 20/40 InterPorp Estimated Pipe Friction = 3300 psi Estimated Perf Friction = 1200 psi BHTP = psi 6 perf clusters Ph = 5000 psi Volume / Cluster = 51,583 gal Surface Treating Pressure = psi 100 mesh / Cluster = 7,917 lb Main Proppant / Cluster = 59,250 lb 20

21 Simultaneous fracturing results Simulfrac or Zipperfrac Typically more microseismic activity Overlapping microseismic behavior Still see general fracturing behavior SPE (Rimrock)

22 Barnett - refrac potential Barnett Shale: Gel Frac Barnett Shale: Refrac Water Frac 1600 SRV vs. 6-month Average Gas Flow Ra ate (Mcf/d) Gel Frac Water Frac SPE (MCFD) 6-Month Average y = x R 2 = Time (days) SRV (10 6 m3) 22

23 Marcellus - more height growth & planar vs. Barnett Experiment Lite frac 3000 ft lateral 6 stages 550,000 gal/stg Barnett 97 bpm rate 100,000 lb/stg Slickwater Typical More planar than Barnett Complexity More stages More perf clusters SPE Range Resources Corp

24 Haynesville - significant height growth Haynesville GMX fracture treatment 3,000 5,000 ft laterals 7 10 stages 300 ft spacing 2 perf clusters/stage Stimulation 300 to 500 K gal/stage 65 bpm rate 270,000 lb proppant/stage Slickwater, hybrid, & X-link SPE GMX Resources

25 Woodford - containment Fracture Lengths Stage 1: 2500 Stage 2: 3300 Stage 2 RF: 1400 Stage 4: 1200 Obs Carr Well Estate #113-1H Pettigrew 19-1H Obs Well #2 Treatment Pettigrew Well 18-1H Fracture Heights Stage 1: 250 Stage 2: 280 Stage 2 RF: 280 Stage 4: 280 Well contained Woodford FM SPE Antero Stage 1 events Stage 2 events Stage 2RF events Stage 3 events Looking NW

26 Utica Woodford Barnett Haynesville Marcellus Eagleford Bakken Porosity (%) 1-8% ~1.5 6 (Avg. ~3.8) 8-15% 3 8% 3-15% 2-12 % TVD (ft) 6,000 14,000 5,400 9,500 10,500 14,000 4,500-8,500 5,000-13,000 8,000-11,000 Thickness (ft) ft & ft BHT ( F) º F TOC (%) 3-9% 4-8% 2-5% 3-10% 0.5-9% Upper-11%-40% Lower=8%-21% Press Grad (psi/ft) Frac Grad (psi/ft).7-.9 ~ > Avg Perm (μd) < Sw (%) 33% <35 no free water < Lithology (%) Silica- Chert 30-60% Silica rich v/v Shale is soft (ductile) Calcite rich-in areas? silica rich (in areas) organic rich High clay mineral fraction Variable formation properties Illite clay-dominated Quartz/Plagioclase/ Feldspar Carbonates Siderite/Pyrite ~3-5% carbon content High Illite-dominate clays Looks like poker chips High in Calcites Silty, sandy, dolomite grading to laminated shaly interval. Some natural fractures. Below is Sanish YM (x10 6 psi) Upper/Lower= 2-4 Middle=4-6 PR (%) Upper/Lower= Middle= Quartz, wt % Plagioclase feldspar, wt % Calcite, wt % Smectite,wt % < Illite, wt % Kaolinite wt % < Chlorite, wt % Ro (Maturity of Shale)

27 Marcellus shale frac height vs aquifer depth

28 Thank You