Attribute Expression of the Mississippi Lime. Attribute expression of the Mississippi Lime

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1 Attribute Expression of the Mississippi Lime Kurt J. (The University of Oklahoma) Attribute expression of the Mississippi Lime Lithology Fractures o Strain o Thickness o Lithology Diagenesis Impedance Curvature Spectral components Impedance Textures 1

2 Outline Correlation of fractures to curvature o Clay models o Outcrop analogues o Hunton Limestone seismic with image logs A proposed workflow using post-stack data o Kansas fractured carbonate Attribute images of Osage County surveys Recommendations for future seismic acquisition Clay model experiments photo k pos from scanned surface (Staples, 2011) 2

3 Clay model experiments photo (Staples, 2011) Clay model experiments k pos from scanned surface (Staples, 2011) 3

4 Clay model experiments (Staples, 2011) Outline Correlation of fractures to curvature o Clay models o Outcrop analogues o Hunton Limestone seismic with image logs A proposed workflow using post-stack data o Kansas fractured carbonate Attribute images of Osage County surveys Recommendations for future seismic acquisition 4

5 negative Deformation of mixed competency rocks (Glen Rose fm) positive negative (Ferrill and Morris, 2008) Deformation of less competent rocks (e.g. Eagleford fm) (Ferrill and Morris, 2008) 5

6 Lidar correlation of fractures on outcrops to curvature (UK) Carboniferous Eelwell limestone (Pearce et al., 2011) Lidar correlation of fractures on outcrops to curvature (UK) (Pearce et al., 2011) 6

7 Lidar correlation of fractures on outcrops to curvature (UK) I endorse this correlation. (Saint Aiden) (Pearce et al., 2011) Outline Correlation of fractures to curvature o Clay models o Outcrop analogues o Hunton Limestone seismic with image logs A proposed workflow using post-stack data o Kansas fractured carbonate Attribute images of Osage County surveys Recommendations for future seismic acquisition 7

8 Hunton Limestone, Central OK (Staples, 2011) Hunton Limestone, Central OK 16 8

9 Most-positive principal curvature, k 1, co-rendered with image log fracture density (Staples, 2011) Strike of most-positive principal curvature, k 1, co-rendered with image log fracture density (Staples, 2011) 9

10 Correlation of fractures with curvature Azimuthal Intensity Correlations to Fracture Density Well Number Azimuth Azimuthal Intensity vs. Fracture Density Correlation (r) Measured Length Along Wellbore (ft) No correlation (Staples, 2011) Correlation of Geometric Attributes to Production The problem Geometric attributes are an indirect measure of the paleo rather than the present-day stress regime Since the time of fracture initiation the direction of S hmax has probably rotated fractures may have been diagenetically altered (cemented, filled, or enlarged) 10

11 A 1 2 Dickman Field (Kansas, USA) Discovered in 1962 Cumulative production >1.7 million bbl oil High water cut (>94%) 3 4 A C.I. = 3 m 1 km Seismic Depth Map of Top Mississippian (Nissen et al., 2005) Volumetric Curvature Gilmore City Horizon Frequency-Azimuth Rose Diagram fault Length-Azimuth Rose Diagram 0.5 mile (Nissen et al., 2005) 11

12 Shale-filled fractures intersected by horizontal well (Kansas, USA) Karst-controlled ft interval Provide a barrier to fluid flow Miissippian cave filled with Pennsylvanian shale, SW Missouri (Nissen et al., 2005) Water production versus distance to nearest NW and NE lineaments No relationship Increased water production near lineaments 0.5 mile (Nissen et al., 2005) 12

13 5 year oil production (x10 4 Bbl) 5 year water production (x10 4 Bbl) 5-yr water production 5 year oil production (x10 4 Bbl) 5 year water production (x10 4 Bbl) 5-yr water production Oriented lineaments -- Kansas Mississippian Lineament trend vs. production yr oil production 5-yr oil production Distance distance to NE to lineament NE (ft) Distance distance to NE to lineament NE (ft) (ft) 0.5 mile 0 Distance to NW lineament (ft) distance to NW lineament (ft) 0 Distance to NW lineament (ft) distance to NW lineament (ft) (Nissen et al., 2005) Methodology Hypothesize that an anomaly at a given azimuth corresponds to an open fracture Assume flow goes as κ/r Correlate flow to production to test the hypothesis Fault plane (permeability, κ >>0) Flow ~κ/r (Guo et al., 2011) 13

14 Filter Amplitude Flow as a function of distance, r, from a natural point injector distance, r r max (Guo et al., 2011) Seismic data Dip scan Workflow to calculate hypothesized fluid flow Inline dip Crossline dip Curvature computation k 1, Ψ 1 k 2, Ψ 2 User thresholds for scaling Azimuthal filtering Azimuthallylimited subset φ 1 Azimuthallylimited subset φ j Azimuthallylimited subset φ N Convolve with 1/r Convolve with 1/r Convolve with 1/r Fluid flow φ 1 Fluid flow φ j Fluid flow φ N (Guo et al., 2011) 14

15 Filter Amplitude Computing azimuthally-limited curvature volumes Strike (Guo et al., 2011) Time (ms) 860 B B B 888 A A B 0.5 mi N A A Top Mississippian Gilmore City Time-structure map of Gilmore City horizon and two seismic lines (Guo et al., 2011) 15

16 weight k 2 N Most negative structural curvature, k 2, through the Gilmore City (Guo et al., 2011) 0.5 mi Skeletonized image obtained by interactively adjusting the color bar N 0.5 mi k 2 k lower k upper (Guo et al., 2011) 16

17 Azimuth ψ N W S E 0 N 0.5 mi k 2 modulated by ψ 2 (Guo et al., 2011) R= R= R= R= mi R= R= R= R= R= R= R= R= (Guo et al., 2011) fluid flow with oil production low Intensity high 17

18 Unpreferred azimuth Preferred azimuth Cross-correlation coefficient R= R= R= R= mi R= R= R= R= R= R= R= R= (Guo et al., 2011) fluid flow with water production low Intensity high Oil production Water production Strike Strike (Guo et al., 2011) 18

19 Outline Correlation of fractures to curvature o Clay models o Outcrop analogues o Hunton Limestone seismic with image logs A proposed workflow using post-stack data o Kansas fractured carbonate Attribute images of Osage County surveys Recommendations for future seismic acquisition Attribute expression of the Mississippi Lime Lithology Fractures o Strain o Thickness o Lithology Diagenesis Impedance Curvature Spectral components Impedance Textures 19

20 Time (s) Rejecting periodic components of seismic noise A 2 mi 500 ms A A 600 ms A Original data Filtered data Rejected noise Rejecting periodic components of seismic noise A A mi Original data Filtered data Rejected noise 20

21 Before data conditioning Time (s) Arbuckle horizon pick After post stack data conditioning Time (s) Arbuckle horizon pick 21

22 Top Mississipian Surface Time (s) Top Mississipian Surface with k 1 curvature Time (s) k 1 Pos 0 Neg Time slice at 0.6 s 22

23 k 1 curvature k 1 Pos 0 Neg Time slice at 0.6 s Coherence k 1 Pos 0 Neg Time slice at 0.6 s 23

24 k 1 curvature co-rendered with coherence k 1 Pos 0 Neg Time slice at 0.6 s k 1 curvature vs. strike co-rendered with coherence Time slice at 0.6 s W Strike ψ N S E 24

25 k 1 curvature vs. strike Time slice at 0.6 s W Strike ψ N S E k 1 curvature vs. strike Time slice at 0.6 s W Strike ψ N S E 25

26 Attribute expression of the Mississippi Lime Lithology Fractures o Strain o Thickness o Lithology Diagenesis Impedance Curvature Spectral components Impedance Textures Texture analysis and self-organizing maps applied to satellite imagery Satellite Self-organizing image map (Matos et al., 2011) 26

27 Time (ms) Vertical slices through texture attributes, Osage Co., OK Cluster color bar (Matos et al., 2011) Texture analysis and self-organizing maps applied to Mississippi Lime, Osage Co, OK good poor? (Matos et al., 2011) 27

28 Outline Correlation of fractures to curvature o Clay models o Outcrop analogues o Hunton Limestone seismic with image logs A proposed workflow using post-stack data o Kansas fractured carbonate Attribute images of Osage County surveys Recommendations for future seismic acquisition Recommendations for future seismic acquisition Acquire high density, but less sweeps (more traces/mi 2 ) reduce coherent noise (e.g. ground roll, shallow diffractors, ) reduce acquisition footprint that overprints fractures Acquire long offsets facilitate λρ-μρ inversion to map lithology (tripolite, dolomite, tight chert, ) Acquire wide azimuth to facilitate AVAz and VVAz analysis map natural fractures map maximum/minimum horizontal stresses Calibrate seismic predictions with image logs and microseismic data These are fairly routine parameters in other resource plays (i.e. shale gas) 28

29 For Financial Support AASPI consortium sponsors Acknowledgements For Seismic Data Spyglass LLC The Osage Nation Pathfinder LLC Mull Drilling Co. 29