University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology

1
University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
Migration of Petroleum
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Problem/conundrum
• Petroleum (organic molecules generally larger
  than water molecules) must move through
  fine-grained sedimentary rock that has been
  compacted and made (more) impermeable to water.
• Another way to look at this conundrum
  shales are seemingly the most abundant seals of
  traps and thus epitomize impermeability to oil
  migration - but shales are the most common source
  rocks and thus necessarily must be rocks out of
  which primary migration takes place.

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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
4
University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Problem/conundrum
• Petroleum (organic molecules generally larger
  than water molecules) must move through
  fine-grained sedimentary rock that has been
  compacted and made (more) impermeable to water.
• Another way to look at this conundrum
  shales are seemingly the most abundant seals of
  traps and thus epitomize impermeability to oil
  migration - but shales are the most common source
  rocks and thus necessarily must be rocks out of
  which primary migration takes place.

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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
Bjørlykke 2010
6
University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Problem/conundrum
• Petroleum (organic molecules generally larger
  than water molecules) must move through
  fine-grained sedimentary rock that has been
  compacted and made (more) impermeable to water.
• Another way to look at this conundrum
  shales are seemingly the most abundant seals of
  traps and thus epitomize impermeability to oil
  migration - but shales are the most common source
  rocks and thus necessarily must be rocks out of
  which primary migration takes place.

7
University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
8
University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Old explanations largely assumed that petroleum
  was sufficient soluble
• that it could be transported in water moving
  out of shales. This
• seems to have been resort to an improbable
  explanation for lack
• of any other.
• Specific concepts
• Expulsion of proto-petroleum molecules (but
  this entity is unknown).
• Transport of petroleum in aqueous solution
  (but hydrocarbons arent soluble).
• Transport in solution of CO2 (but production
  of CO2 is not coincident with generation
• of petroleum).
• Transport by micelles (soap-like molecules
  with a hydrophyllic end (thus soluble in
• water) and a hydrophobic end (to which
  organic molecules can bond)
• (but micelles are uncommon).

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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Old explanations largely assumed that petroleum
  was sufficient soluble
• that it could be transported in water moving
  out of shales. This
• seems to have been resort to an improbable
  explanation for lack
• of any other.
• Specific concepts
• Expulsion of proto-petroleum molecules (but
  this entity is unknown).
• Transport of petroleum in aqueous solution
  (but hydrocarbons arent soluble).
• Transport in solution of CO2 (but production
  of CO2 is not coincident with generation
• of petroleum).
• Transport by micelles (soap-like molecules
  with a hydrophyllic end (thus soluble in
• water) and a hydrophobic end (to which
  organic molecules can bond)
• (but micelles are uncommon).

10
University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Old explanations largely assumed that petroleum
  was sufficient soluble
• that it could be transported in water moving
  out of shales. This
• seems to have been resort to an improbable
  explanation for lack
• of any other.
• Specific concepts
• Expulsion of proto-petroleum molecules (but
  this entity is unknown).
• Transport of petroleum in aqueous solution
  (but hydrocarbons arent soluble).
• Transport in solution of CO2 (but production
  of CO2 is not coincident with generation
• of petroleum).
• Transport by micelles (soap-like molecules
  with a hydrophyllic end (thus soluble in
• water) and a hydrophobic end (to which
  organic molecules can bond)
• (but micelles are uncommon).

11
University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Old explanations largely assumed that petroleum
  was sufficient soluble
• that it could be transported in water moving
  out of shales. This
• seems to have been resort to an improbable
  explanation for lack
• of any other.
• Specific concepts
• Expulsion of proto-petroleum molecules (but
  this entity is unknown).
• Transport of petroleum in aqueous solution
  (but hydrocarbons arent soluble).
• Transport in solution of CO2 (but production
  of CO2 is not coincident with generation
• of petroleum).
• Transport by micelles (soap-like molecules
  with a hydrophyllic end (thus soluble in
• water) and a hydrophobic end (to which
  organic molecules can bond)
• (but micelles are uncommon).

12
University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Old explanations largely assumed that petroleum
  was sufficient soluble
• that it could be transported in water moving
  out of shales. This
• seems to have been resort to an improbable
  explanation for lack
• of any other.
• Specific concepts
• Expulsion of proto-petroleum molecules (but
  this entity is unknown).
• Transport of petroleum in aqueous solution
  (but hydrocarbons arent soluble).
• Transport in solution of CO2 (but production
  of CO2 is not coincident with generation
• of petroleum).
• Transport by micelles (soap-like molecules
  with a hydrophyllic end (thus soluble in
• water) and a hydrophobic end (to which
  organic molecules can bond)
• (but micelles are uncommon).

13
University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Old explanations largely assumed that petroleum
  was sufficient soluble
• that it could be transported in water moving
  out of shales. This
• seems to have been resort to an improbable
  explanation for lack
• of any other.
• Specific concepts
• Expulsion of proto-petroleum molecules (but
  this entity is unknown).
• Transport of petroleum in aqueous solution
  (but hydrocarbons arent soluble).
• Transport in solution of CO2 (but production
  of CO2 is not coincident with generation
• of petroleum).
• Transport by micelles (soap-like molecules
  with a hydrophyllic end (thus soluble in
• water) and a hydrophobic end (to which
  organic molecules can bond)
• (but micelles are uncommon).

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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
Selley 1998
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Old explanations largely assumed that petroleum
  was sufficient soluble that it could be
  transported in water moving out of shales. This
  seems to have been resort to an improbable
  explanation for lack
• of any other.
• Primary hydrocarbon generation . . . is to
  many people the last great mystery of petroleum
  geology
• R.C. Selley (1998) Elements of
  Petroleum Geology (2nd edn)

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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• Primary migration - passage of petroleum out of
  the source rock in which it was generated.
• Old explanations largely assumed that petroleum
  was sufficient soluble that it could be
  transported in water moving out of shales. This
  seems to have been resort to an improbable
  explanation for lack
• of any other.
• Newer (post 1990s) explanations assumed petroleum
  travels on its own (not in solution) and that
  pressure resulting from increased volume in
  maturation causes its expulsion directly, or
  causes fracturing that allows primary migration.

Mackenzie et al., 1987, The expulsion of
petroleum from Kimmeridge Clay source rocks in
the area of the Brae Oilfield, U.K.
continental shelf, in Brroks Glennie, eds.,
Petroleum Geology of North West Europe
(London, Graham and Trotman), p. 865-877. (See
GS p. 141 ff. England and Fleet, 1991, Petroleum
Migration Geological Society of London Special
Publicaton 59. Warning Selley (1998) devoted
lots of attention to solubility-based ideas
Assaad (2009) still said petroleum is
soluble, citing Levorsen (1954)!
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
Bjørlykke 2010
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
Bjørlykke 2010
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• A. Primary migration - passage of petroleum out
  of the source rock in which it was generated.
• B. Secondary migration - passage of petroleum
  through porous and
• permeable media, driven by buoyancy contrast
  between petroleum
• and water that otherwise fills porosity.
• Media
• Porous and permeable sands and sandstones.
• Porous and permeable carbonate sediments and
  rocks.
• Fractures and faults.
• The first two, or all three, are potential
  reservoir rocks.
• C. Tertiary migration

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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• A. Primary migration - passage of petroleum out
  of the source rock in which it was generated.
• B. Secondary migration - passage of petroleum
  through porous and
• permeable media, driven by buoyancy contrast
  between petroleum
• and water that otherwise fills porosity.
• Media
• Porous and permeable sands and sandstones.
• Porous and permeable carbonate sediments and
  rocks.
• Fractures and faults.
• The first two, or all three, are potential
  reservoir rocks.
• C. Tertiary migration

25
University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• A. Primary migration - passage of petroleum out
  of the source rock in which it was generated.
• B. Secondary migration - passage of petroleum
  through porous and
• permeable media, driven by buoyancy contrast
  between petroleum
• and water that otherwise fills porosity.
• Media
• Porous and permeable sands and sandstones.
• Porous and permeable carbonate sediments and
  rocks.
• Fractures and faults.
• The first two, or all three, are potential
  reservoir rocks.
• C. Tertiary migration

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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
Petroleum System
Spill Point
1) Early Generation
Spill Point
Seal Rock (Mudstone)
Reservoir Rock (Sandstone)
Migration from Kitchen
Gas beginning to displace oil
2) Late Generation
Displaced oil accumulates
Gas displaces all oil
From a U of OK course ppt file
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
An example from Pakistan, from a U of OK course
ppt file
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
Selley 1998
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• A. Primary migration - passage of petroleum out
  of the source rock in which it was generated.
• B. Secondary migration - passage of petroleum
  through porous and
• permeable media, driven by buoyancy contrast
  between petroleum
• and water that otherwise fills porosity.
• Media
• Porous and permeable sands and sandstones.
• Porous and permeable carbonate sediments and
  rocks.
• Fractures and faults.
• The first two, or all three, are potential
  reservoir rocks.
• (more to follow)

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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology

• VIII. Migration
• A. Primary migration - passage of petroleum out
  of the source rock in which it was generated.
• B. Secondary migration - passage of petroleum
  through porous and
• permeable media, driven by buoyancy contrast
  between petroleum
• and water that otherwise fills porosity.
• Media
• Porous and permeable sands and sandstones.
• Porous and permeable carbonate sediments and
  rocks.
• Fractures and faults.
• The first two, or all three, are potential
  reservoir rocks.
• C. Tertiary migration

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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
Gluyas Swarbrick 2004, in a
very North-Sea example
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University of Georgia Department of Geology GEOL
4320 Petroleum Geology
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
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University of Georgia Department of Geology GEOL
4320/6320 Petroleum Geology
Sources
White sans-serif Helvetica text
Asquith and Krygowski 2004
Light gray Times New Roman text
Assaad 2008
AAPG Basic Well Log Analysis course notes
White sans-serif Helvetica text
Baker-Hughes Atlas of Log Responses
Bjørlykke 2010
Conaway 1999
Crains Petrophysical Handbook
Title
Glovers Petrophysique
Gluyas Swarbrick 2004
North 1980
Jonathan B. Martin UF class notes
Rigzone
Schlumberger Log Interpretation PI
Schlumberger Oilfielld Glossary
Selley 1998
Shell Petroleum Handbook (1983)
Notes
Shepherd 2009
Tissot Welte (1984)
Wikipedia