Phi K from Log help

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soman703
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Phi K from Log help

Post by soman703 »

Hello everyone,
I have a question.I am dealing with a sandstone reservoir.
And I have SP. Swi and Density log avaulable.
Can anyone give me detailed idea on how can I compute porosity and Permeability from this log data?
Its in attachments.

Thankyou,
Soman
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FANARCO
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Re: Phi K from Log help

Post by FANARCO »

soman703 wrote:Hello everyone,
I have a question.I am dealing with a sandstone reservoir.
And I have SP. Swi and Density log avaulable.
Can anyone give me detailed idea on how can I compute porosity and Permeability from this log data?
Its in attachments.

Thankyou,
Soman
This log is not complete.

For porosity i think can be determined from log but permeability may be there are indirect calculation by correlations, let me check and inform you.
Leszek
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Joined: Wed Jan 19, 2011 3:29 pm

Re: Phi K from Log help

Post by Leszek »

From data like that it is possible to calculate porosity from density, and apparent permeability from porosity.
Unfortunately your curves look like crap. Curves were at least blocked or something.
If your data was correct, try this:

Density porosity:
PHID = (DENSlog - DENSMATRIX) / (DENSFLUID - DENSMATRIX), where:
DENSlog - your density log values
DENSMATRIX - 2.71 for limestone scale, 2.65 for sandstone scale
DENSFLUID - 1.0 for fresh water mud, 1.1 For salty water mud

Apply density shale correction:
PHIDSH = (DENSH - DENSMA) / (DENSW - DENSMA), where
DENSSH - density of shale taken from log data (usually between 2.4 and 2.7, check average RHOB values in 100% shale)

PHIe = PHID - Vsh * PHIDSH, where
Vsh is shale volume

Now when you have effective porosity (PHIe), you can calculate permeability:

PERMp = 10 ^ (HPERM * PHIe + JPERM), where

JPERM = permeability constant (fractional)
HPERM = porosity exponent (fractional)
PERMp = calculated permeability (millidarcies)
PHIe = effective porosity (fractional)

RECOMMENDED PARAMETERS:
ROCK TYPE HPERM JPERM
Carbonates
chalky 10 - 20 -2.5
fine sucrosic or
intercrystalline 20 - 30 -2.5
coarse sucrosic or
intercrystalline 25 - 50 -2.5
small vuggy 30 - 100 -2.5
large vuggy 50 - 200 -2.5
fractures 200 - 300 -3.0

Sandstones
very fine grains 10 - 20 -3.0
fine grains 15 - 25 -3.0
medium grains 20 - 30 -3.0
large grains 25 - 50 -3.0
conglomerate 20 - 50 -3.0
unconsolidated 20 - 50 -3.5
fractures 200 - 300 -3.0

And cut all values of permeability above 20000 milidarcy - it is not reasonable.

I hope this would help
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FANARCO
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Re: Phi K from Log help

Post by FANARCO »

Leszek wrote:From data like that it is possible to calculate porosity from density, and apparent permeability from porosity.
Unfortunately your curves look like crap. Curves were at least blocked or something.
If your data was correct, try this:

Density porosity:
PHID = (DENSlog - DENSMATRIX) / (DENSFLUID - DENSMATRIX), where:
DENSlog - your density log values
DENSMATRIX - 2.71 for limestone scale, 2.65 for sandstone scale
DENSFLUID - 1.0 for fresh water mud, 1.1 For salty water mud

Apply density shale correction:
PHIDSH = (DENSH - DENSMA) / (DENSW - DENSMA), where
DENSSH - density of shale taken from log data (usually between 2.4 and 2.7, check average RHOB values in 100% shale)

PHIe = PHID - Vsh * PHIDSH, where
Vsh is shale volume

Now when you have effective porosity (PHIe), you can calculate permeability:

PERMp = 10 ^ (HPERM * PHIe + JPERM), where

JPERM = permeability constant (fractional)
HPERM = porosity exponent (fractional)
PERMp = calculated permeability (millidarcies)
PHIe = effective porosity (fractional)

RECOMMENDED PARAMETERS:
ROCK TYPE HPERM JPERM
Carbonates
chalky 10 - 20 -2.5
fine sucrosic or
intercrystalline 20 - 30 -2.5
coarse sucrosic or
intercrystalline 25 - 50 -2.5
small vuggy 30 - 100 -2.5
large vuggy 50 - 200 -2.5
fractures 200 - 300 -3.0

Sandstones
very fine grains 10 - 20 -3.0
fine grains 15 - 25 -3.0
medium grains 20 - 30 -3.0
large grains 25 - 50 -3.0
conglomerate 20 - 50 -3.0
unconsolidated 20 - 50 -3.5
fractures 200 - 300 -3.0

And cut all values of permeability above 20000 milidarcy - it is not reasonable.

I hope this would help
It is more than help,

Thanx
soman703
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Posts: 93
Joined: Sun Nov 29, 2015 10:34 am

Re: Phi K from Log help

Post by soman703 »

Thankyou soo much sir!!

amazing.
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