8/14/2019 3.Porosity

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Stanford Rock Physics Laboratory - Gary Mavko

Porosity

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POROSITY is defined as the ratio of pore volume tototal volume:

where:is the porosity

is the pore volume

is the solid volume

is the total volume

Be careful of different definitions of porosity!

total porosity  = total non-mineral space

connected porosity  = pore space connected to the

exterior of sample

disconnected or  = space not well connected

trapped porosity 

Also in well logging: neutron porosity, density porosity, etc.

φ =vP

vT 

=

vT − v

S 

vT 

φ vP

vS 

vT 

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