Rock Components
04.2015 Dak
Basic Rock Components
Clastic Rock Components
non-move
fluids
hydrocarbons
free
water
hydrocarbons
Solidity: 1 - PhiT
residual
HC
water
water
-
clay&
OH-
water
residual
HC
matrix
quartz, feldspar, etc.
porosity
OH
dry clay
grains
moveable fluids
claybound
capillarybound
Clastic
Components
solid matrix
mud, silt
Clastic
Rock
nonmoveable
fluids
porosity
Simplified
Rock
Total porosity, PhiT
Grain volume
Bulk Volume Water
Bulk volume hydrocarbons
Carbonate Rock Components
Total porosity, PhiT
Bulk volume hydrocarbons
cap.-bound
hydrocarbons
free
water
resid. HC
porosity
interparticle
vuggy
cap.-bound
cement
grains
resid. HC
hydrocarbons
Bulk Volume Water
mud
by porosity
free water
Solidity: 1 - PhiT
Grain volume
Carbonate
Rock
non-move
fluids
non-move
fluids
porosity
cap.bound
grains
moveable fluids
free water
by fluid
solid matrix
cement
Carbonate
Rock
porosity
mud
Simplified
Rock
hydrocarbons
Solidity: 1 - PhiT
Grain volume
ads.gas
gas, oil
ads.gas
water
OH
gas, oil
free
water
clay & OH-
water
dry clay
quartz, carbonate, pyrite,
etc.
porosity
claybound
Organic Shale
Components
mineral matrix
kerogen
Organic
Shale
kerogen
Organic Shale Components
Total porosity, PhiT
BVW
Bulk Vol.HC
Clavaud, 2006; Eslinger & Pevear, 1988; Lewis, 2011, American Petroleum Institute, 1998; Wikipedia, 2012; Ingraham & Shipps, 2012
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Rock Components
04.2015 Dak
Clastic Rock Components
clay&
OH-
water
hydrocarbons
free
water
hydrocarbons
Solidity: 1 - PhiT
residual
HC
water
water
OH
-
porosity
residual
HC
Clastic
Components
matrix
quartz, feldspar, etc.
moveable fluids
claybound
capillarybound
grains
dry clay
Clastic
Rock
mud, silt
solid matrix
non-mov.
fluids
nonmoveable
fluids
porosity
Simplified
Rock
Total porosity, PhiT
Grain volume
Bulk Volume Water
Bulk volume hydrocarbons
Component definitions
dry clay
Clay/Shale
Definitions
CBW
Vshale
V. wet shale
V. dry shale
Saturation
Definitions
PhiESwe
PhiESwt
PhiE (1-Swe)
PhiT (1-Swt)
Effective porosity, PhiE
Porosity
Definitions
Total porosity, PhiT
Water-filled porosity
Porosity Measurements
Apparent density porosity, PhiD
Water- or oil-filled; NOT gas.
(For all these measurements)
Porosity
from logs
Apparent neutron porosity, PhiN
Apparent sonic porosity, PhiS
High frequency resistivity/dielectric
PhiEPT
NMR total porosity
Nuclear Magnetic Resonance
bound
NMR free fluids
NMR non-clay fluids
Porosity
from cores
Laboratory at net overburden pressure.
Porosity measured at ambient conditions will
be higher than that measured at overburden.
Humidity-dried, gas injection or resaturation
Vacuum oven-dried, gas injection or resaturation
Disaggregation of sample
Clavaud, 2006; Eslinger & Pevear, 1988; Lewis, 2011, American Petroleum Institute, 1998; Wikipedia, 2012; Ingraham & Shipps, 2012
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Rock Components
04.2015 Dak
Carbonate Rock Components
by fluid type
free water
Saturation
Definitions
PhieSwe
Total porosity, Phit
NMR total porosity
Porosity
from cores
NMR free fluids
bound
NMR non-clay fluids
Nuclear Magnetic Resonance
cap.-bound
hydrocarbons
cap.-bound
free water
grains
porosity
interparticle
vuggy
free
water
resid. HC
Water- or oil-filled; NOT gas.
hydrocarbons
Interparticle/Intercrystalline porosity
Porosity
Definitions
Porosity
from logs
Phit (1-Swt)
Water-filled porosity
cement
by porosity type
Phie (1-Swe)
Effective porosity, Phie
mud
Carbonate
Rock
hydrocarbons
PhitSwt
Porosity
Definitions
Porosity
from logs
non-mov.
fluids
non-move
fluids
porosity
resid. HC
grains
moveable fluids
cap.bound
solid matrix
cement
Carbonate
Rock
porosity
mud
Simplified
Rock
Total porosity, Phit
Vuggy porosity
Apparent density porosity, PhiD
Water- or oil-filled; NOT gas.
(For all these measurements)
Apparent neutron porosity, PhiN
Apparent sonic porosity, PhiS
Laboratory at net overburden pressure.
Porosity measured at ambient conditions will
be higher than that measured at overburden.
Humidity-dried, gas injection or resaturation
Vacuum oven-dried, gas injection or resaturation
Disaggregation of sample
Clavaud, 2006; Eslinger & Pevear, 1988; Lewis, 2011, American Petroleum Institute, 1998; Wikipedia, 2012; Ingraham & Shipps, 2012
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Rock Components
04.2015 Dak
Carbonate Rock Components by fluid type
by fluid type
free water
Saturation
Definitions
Porosity
from cores
hydrocarbons
PhieSwe
Phie (1-Swe)
PhitSwt
Phit (1-Swt)
Effective porosity, Phie
Porosity
Definitions
Porosity
from logs
non-move
fluids
non-move fl
porosity
resid. HC
grains
moveable fluids
cap.bound
solid matrix
cement
Carbonate
Rock
porosity
mud
Simplified
Rock
Total porosity, Phit
Water-filled porosity
NMR total porosity
Water- or oil-filled; NOT gas.
bnd
NMR free fluids
NMR non-clay fluids
Nuclear Magnetic Resonance
Humidity-dried, gas injection or resaturation
Laboratory at net overburden pressure.
Porosity measured at ambient conditions will
be higher than that measured at overburden.
Vacuum oven-dried, gas injection or resaturation
Disaggregation of sample
Clavaud, 2006; Eslinger & Pevear, 1988; Lewis, 2011, American Petroleum Institute, 1998; Wikipedia, 2012; Ingraham & Shipps, 2012
cap.-bound
hydrocarbons
free
water
hydrocarbons
resid. HC
porosity
interparticle
vuggy
free water
by porosity type
grains
cement
Carbonate
Rock
mud
Carbonate Rock Components by porosity type
Interparticle/Intercrystalline porosity
Porosity
Definitions
Total porosity, Phit
Vuggy porosity
Apparent density porosity, PhiD
Porosity
from logs
Water- or oil-filled; NOT gas.
(For all these measurements)
Apparent sonic porosity, PhiS
NMR total porosity
Nuclear Magnetic Resonance
Porosity
from cores
Apparent neutron porosity, PhiN
Laboratory at net overburden pressure.
Porosity measured at ambient conditions will
be higher than that measured at overburden.
NMR non-clay fluids
Humidity-dried, gas injection or resaturation
Vacuum oven-dried, gas injection or resaturation
Disaggregation of sample
Clavaud, 2006; Eslinger & Pevear, 1988; Lewis, 2011, American Petroleum Institute, 1998; Wikipedia, 2012; Ingraham & Shipps, 2012
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Rock Components
04.2015 Dak
ads.gas
gas, oil
ads.gas
water
gas, oil
free
water
clay & OH-
water
OH
-
dry clay
quartz, carbonate, pyrite,
etc.
porosity
claybound
Organic Shale
Components
mineral matrix
kerogen
Organic
Shale
kerogen
Organic Shale Components
Component definitions
Clay/Shale
dry clay
CBW
Vshale
Effective porosity, Phie
Porosity
Total porosity, Phit
Water-filled
Saturation
Phie
Swe
PhitSwt
Phie (1-Swe)
Phit (1-Swt)
Clavaud, 2006; Eslinger & Pevear, 1988; Lewis, 2011, American Petroleum Institute, 1998; Wikipedia, 2012; Ingraham & Shipps, 2012
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Rock Components
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Comments:
The illustrations here attempt to show basic components of clastic and carbonate reservoirs, and of
organic shales. The original work was done by J.B. Clavaud at Chevron in 2006, and has been
expanded since then. This is a work in progress, especially in organic shales, as our understanding of
the physical properties of the shales and the responses of the logging measurements to those
properties increases.
References
American Petroleum Institute, 1998, Recommended Practices for Core Analysis, Second Edition,
Recommended Practice (RP) 40, February.
Clavaud, J.B., 2006, personal communication, from figure “Basic Petrophysical Definitions.”
Eslinger, E. and Pevear, D., 1988, “Clay Minerals for Petroleum Geologists and Engineers”, SEPM
Short Course No.22.
Ingraham, Andrew, James Shipps, 2012, personal communication at Weatherford Labs, Golden,
Colorado, August 1.
Lewis, Rick, 2011, AAPG Basic Well Log Analysis course, figures from course notes.
Wikipedia, 2012, en.wikipedia.org/wiki/Effective_porosity; accessed 06.11.2012.
This document is intended to be updated periodically as necessary to include new and corrected
information.
Questions and comments about this document are welcomed and encouraged. Please contact Dan
Krygowski at The Discovery Group; [email protected].
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