Fracture Properties Needed

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Fracture Properties Needed
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Fracture porosity permeability are both a
function of Fracture Width (e) Fracture
Spacing (D)
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Fracture Porosity
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Fracture Porosity Magnitude
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Fracture Porosity is Difficult to Calculate and
Even More Difficult to Interpret
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While Fracture Porosity is Small in Magnitude

• It is very effective porosity
• A possible large volume per well due to large
  drainage area and reservoir thickness
• An assumed high recovery factor

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Fracture System Volume as a Function of Fracture
Porosity Drainage
Nelson (1985)
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Fracture Porosity Scale
2 ft
Nelson (1985)
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Depth Depletion Corrections Are Much More
Severe in Fracture Porosity Than in Matrix
Porosity
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Fracture Matrix Porosity Compressibility
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Fracture Matrix Permeability Compressibility
Tr Ss from Daw Others
(1974)
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Fracture Porosity Calculator
Nelson (1985)
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Fracture Porosity Determinations
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Fracture Porosity from Core Analysis
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Fracture Porosity vs. Fracture Permeability
Nelson (1985)
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K. North Sea Chalk Valhall Field
Fracture Porosity/ Permeability Relationship
Nelson (1985)
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Fracture Porosity from Outcrop Fracture
Intensities
Nelson (1985)
Assumes Fracture Width for Ls at 10,000 ft from
Lab Measurements
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Sometimes Fracture Porosity Matrix Porosity are
Related
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Calcite Filled Vessicle Trains Surrounding
Fractures in Tert. Basalt
West Rozel, Great Salt Lake, Utah
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Matrix Saturation Around Fractures in Tert. Basalt
West Rozel, Great Salt Lake, Utah
Calcite fill in Outcrop
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Calcite Along Vessicle Trains Along Fractures in
Basalt
West Rozel, Great Salt Lake, Utah