Microseismic Fracture Mapping Results in the Woodford Shale

Transcription

1 Microseismic Fracture Mapping Results in the Woodford Shale Oklahoma Gas Shales Conference Oklahoma Geological Survey October 22, 2008 Mike Mayerhofer Pinnacle Technologies

2 Introduction Microseismic Mapping Fracturing Shale Reservoirs

3 RECEIVERS RECEIVER PLACEMENT Above Reservoir Minimizes Head Waves Straddling Reservoir Best Viewing Position Smallest Velocity Effects Most Accurate Height Best Hodograms (Directionality) MICROSEISMS RECEIVERS RESERVOIR FRACTURE

4 Microseismic Monitoring Plan View Azimuth The Detection And Locating Of Micro-Earthquakes Induced By Hydraulic Fractures To Map Out The Geometry & Characteristics Of The Hydraulic Fracture Side View Complexity Height Growth Asymmetry Length

5 Fracture Complexity & Network Growth Simple Fracture Complex Fracture Complex Fracture With Fissure Opening Complex Fracture Network

6 Network Fracture Conductivity Primary Hydraulic Fracture Likely Extensive Sand Banking & Transport Distances Orthogonal Network Fractures Proppant Behavior Proppant Can Turn Corner Smaller Width, Lower Rate In Orthogonal Fractures Results In Less Efficient Transport Proppant Bridging (May Enhance Fracturing) 100 Mesh Shear Offset Microseismic Events Are Shear Slippages High Shear Environment Due To Massive Fracture Planes With Different Pressures Aligned Offset

7 Woodford Shale Type Log Thickness ranges from ft Main exploitation with long horizontal wells and large slickwater fracs Lateral lengths ft 10,000 30,000 bbls/stage 200k 500k lbs proppant/stage Barnett-style stimulations to maximize stimulated reservoir volume (SRV)

8 Woodford Mapping Project SPE Early stages of development in the Woodford Objective measure hydraulic fracture geometry in order to optimize future well locations and completion/stimulation design Wellbore Trajectory Land the lateral high, low or midway within the Woodford? Transverse or longitudinal fracs being created? Payzone coverage (fracture height & lateral depth) Wellbore Coverage (along the lateral) Diversion & Staging Methods Perf balls, bridge plug, frac staging systems, etc. Well Spacing

9 Project 1 Layout Horizontal well mapped 3 stages MSM 1 ReFrac Observed Stage 1 and 2 from Obs. Well #1 Obs. Well #1 Carr Estates 13 Tool Array - 1H 2,700 2,700 2,600 2,600 2,800 Treatment Pettigrew 18well Treatment well - 1H 3,500 3,500 2,600 2,600 1,500 1,500 Observed Stage 2 ReFrac and 3 from Obs. Well #1 and Obs Well #2 Stage 2 ReFrac and Stage 3 preformed approx 40 days following initial treatments 17-28K bbls Slickwater BPM Pettigrew 19 Obs Well #2 - Tool Array - 1H 70k-550k lbs 30/70-20/40 sand

10 Project 1 Plan View N57 E E Carr Estates 13 - Obs Well #1 Tool Array - 1H Treatment Pettigrew 18 well Treatment well - 1H Stage 1 Stage 1 Stage 2 Stage 2 Stage 2 RF Stage 2 RF Stage 3 Stage 3 Three stages Complex growth wide network Data affected by Feature (fault or natural fracture system) Azimuth N57 o E Frac lengths ft Asymmetry Pettigrew 19 Obs Well #2 Tool Array - 1H

11 Project 1 Edge View Fracture Lengths Stage 1: 2500 Stage 2: 3300 Stage 3: 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 3: 280 Stage 4: 280 Well contained Woodford FM Stage 1 events Stage 2 events Stage 2RF events Stage 3 events Looking NW

12 Project 1 Side View Carr Obs Estate Well 13-1H #1 Pettigrew Obs Well 19-1H #2 Woodford- Obs. well frac well Treatment Pettigrew Well 18-1H Looking NE

13 Project 3 Layout Observation Well 2,800 3,000 3,400 3,800 4,300 Treatment well Horizontal well mapped 5 stages MSM 4300 ft to stage 5 Observed Stage 1-5 from Obs. Well # K bbls Slickwater BPM 100-mesh sand for diversion 70k-370k lbs 30/70-20/40 sand

14 Project 3 Map View 5 intervals Data affected by Fault Azimuth N60 o E Fracture lengths 1,300 4,300 ft Asymmetry Observation Well Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 Treatment well

15 Project 3 Side View Fracture Lengths Stage 1: 2130 Stage 2: 4360 Stage 3: 3400 Stage 4: Stage 5: Fracture Heights Stage 1: 350 Stage 2: 500 Stage 3: 250 Stage 4: Stage 5: Caney Shale Mayes Sycamore Woodford Shale Hunton Viola Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 MS Tools Looking West

16 Project 3 Magnitude Vs. Distance Plot

17 Barnett vs Woodford Barnett Woodford Stage 1 1 Stage 2 2 Stage 2 RF 2 RF 2200 Stage South-North (ft) N57 E E Treatment Well Carr Estates 13 Obs Well #1-1H Observation Well Tool Array st Stage 2nd Stage Treatment Pettigrew 18 well - 1H Treatment well West-East (ft) Pettigrew 19 Obs Tool Array Well #2-1H

18 Barnett vs Woodford NW SE Obs Carr Well Estate #1 13-1H Pettigrew 19-1H Obs Well # Treatment Pettigrew Well 18-1H 7000 Depth (ft) Upper Barnett Woodford FM Lower Barnett Stage 1 Stage Distance Along Wellbore (ft) Stage 1 events Stage 2 events Stage 2RF events Stage 3 events Looking NW

19 Mapping Data and Production

20 Stimulated Reservoir Volume (SRV) Σ (SRA X h)

21 SRV vs. 6-month Average All Wells SRV= Stimulated Area x Net Pay 6-Month Average (MCFD) y = x R 2 = SRV (10 6 ft3)

22 Stimulated Reservoir Volume (Woodford vs Barnett) SRV (10 6 ft 3 ) Project Cumulative Frequency

23 Hydraulic Fracture Network Model SRV = 1,200 x 10 6 ft^3 Frac Spacing=400 ft SRV = 1,200 x 10 6 ft^3 After 1 Year k = md (matrix) After 15 Years Conductivity = 4 md.ft 1,500 ft 1,000 ft Treatment Horizontal Well 2,000 ft Treatment Horizontal Well

24 Network Size, Frac Spacing and Conductivity are Key For Production From Shale Networks Size Frac Spacing Conductivity

25 Summary Mapping completed in three wells in the Woodford Shale Observation distances similar to the Barnett (core area) Dominant fracture azimuth is NE (more east-west than in Barnett) Project 1 N57 o E Avg. Project 2 N60 o E Avg. Project 3 N60 o E Avg. Indications of complexity (more complex than Barnett) MS data show secondary azimuths Possible fracture network Strong interaction with faults

26 Summary Woodford Fracs fairly contained in the 3 projects Network lengths up to 4,000 ft; Asymmetric Growth (Up-Dip in one case) SRV s can be similar to the Barnett but complexity is higher Mapping indicates that faults and dip can affect the created fracture geometry Reviewing fracture staging strategy Diversion (100 mesh) can help if the fault is relatively small Development continues in this field Using fracture geometry from mapping to assist with locating wells

27 Questions?