A. S. Wylie, Jr. and J. R. Wood Michigan Technological University Permeability and Porosity Imaging of a Niagaran Reef Permeability [md] 30 A. S. Wylie, Jr. and J. R. Wood Michigan Technological University

Niagaran Reef Trend Field Location Belle River Mills Gill (1977)

Niagaran Reef – Generalized Facies Salina Evaporite and Carbonate Units Enclose Reefs STROMATOLITE MAP (next) BOUNDSTONE REEF CONGLOMERATE WACKESTONE 500 ft VE 2X Time Surface ? Debatable 500 ft after Gill (1977)

Belle River Mills Structure Map Top Reef XSEC N Belle River Mills Structure Map Top Reef 10 11 Maximum height 400 ft above Non-reef Brown Niagaran Deviated well -1900 14 -1600 Cored Well (34 total) 0.5 mile CI: 50 ft Reef Well Reef Rubble Well

Niagaran Stratigraphy Belle River Mills –Rock Types MAP (previous) Rock Type Color Codes Gill (1977)

Core – Porosity & Permeability (all samples in Reef by Rock Type) Avg-11 md (761) [13, 100-7000] Avg-10.7% (761) 35 100 Avg-260 md (2259) [416, 100-7000] Avg-10.7% (2259) 35 100 Avg-79 md (1824) [231, 100-7000] Avg-9.4% (1824) 35 100 Avg-48 md (177) [22, 100-7000] Gill (1977) Avg-9.9 (177) Number of samples (###) 35 100

Core Phi vs. Perm – By Rock Type STROMATOLITE n=1824 WACKESTONE n=761 Permeability (md) CONGLOMERATE BOUND STONE n=177 Porosity (%) n=2259

Visualization Orientation – 2D and 3D example views Vertical Exaggeration (VE) – 1X to 10X

Visualization Animation Example – Permeability 25 – 30+ millidarcies Stromatolite Wackestone non-reef Niagaran Boundstone Conglomerate cored interval VE 10X

Reef Permeability Cumulative Percent – all samples 30 md (70%) > 30 md RESET to 30 md Percent 4980 samples Core Permeability (millidarcies)

Reef Permeability – By Rock Type 30 md (70%) > 30 md RESET to 30 md Percent 4980 samples Core Permeability (millidarcies)

Permeability Distribution red voxels are 27 – 30+ millidarcies VE 10X Many other methods for modeling permeability

Log Curve Amplitude Slicing - Review WEST EAST Any regularly sampled data from boreholes SLICES Top Reef (e.g. Log or Core curve data) One or more correlative, bounding time-surfaces 250 ft Base Reef, Time-surface (?) 0.5

Niagaran Core – One Permeability Slice 31 Wells Slicing Bottom Up 0 100md Belle River Mills Reef Limit 23672 (log scale) 23672 PERM CURVE Zero Perm Boundary SLICE 175 N Contour Interval 4 millidarcies 1 mile Well/Core Control Point

Niagaran Core Permeability Animation 31 Wells Slicing Bottom Up 0 100md Belle River Mills Reef Limit 23672 (log scale) N Contour Interval 4 millidarcies 1 mile Well/Core Control Point

Reef Porosity – By Rock Type Cumulative Percent Core Porosity (%) 4980 samples

Niagaran Core – One Porosity Slice 31 Wells Slicing Bottom Up PHI 0 20% Belle River Mills Reef Limit 23672 23672 PHI CURVE SLICE 175 Zero Phi Boundary Contour Interval 4% porosity N 1 mile Well/Core Control Point

Niagaran Core Porosity Animation 31 Wells Slicing Bottom Up PHI 0 20% Belle River Mills Reef Limit 23672 Contour Interval 4% porosity N 1 mile Well/Core Control Point

Key Trends – Core Perm, Core Phi & GR Core Permeability Core Porosity Gamma Ray Slice 324 Uppermost BOUNDSTONE more control wells Slice 145 WACKESTONE

What can we do with these models ?

2D and 3D Visualization aids interpretation of Permeability and Porosity Trends in the Reef ( 25+ md ) VE 10X Better targeting analysis for vertical and horizontal wells

Perforated Intervals versus Permeability 20 - 30+ md 10X Perforated interval (original) Improved completions, secondary, and tertiary projects

Best Storage versus Best Deliverability BEST POROSITY BEST PERMEABILITY ( > 13% ) ( 25+ md ) Perforated interval VE10X Best Storage versus Best Deliverability

Storage and Deliverability vs. Rock Type BEST POROSITY BEST PERMEABILITY ( > 13% ) ( 25+ md ) Rock Types VE10X Storage and Deliverability vs. Rock Type

Results/Conclusions Location of best porosity (storage capacity) and best permeability (deliverability) does not always coincide in the reservoir (reef) Existing well data used to model reservoir porosity and permeability distribution Methodology uses affordable software