University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology Migration of Petroleum
University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology Migration of Petroleum Conventional
University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology Migration of Petroleum Conventional (and the petroleum of tar sands, before it is tarry)
VIII. Migration A.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. 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. 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. University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology
Bjørlykke 2010
VIII. Migration A.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. 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. 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 aren’t soluble). Transport in solution of CO 2 (but production of CO 2 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). Flushing of hydrocarbons with water generated by dehydration of smectite in its conversion to illite (but this involves either solution of hydrocarbons or pushing large molecules through small pores). 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. 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 aren’t soluble). Transport in solution of CO 2 (but production of CO 2 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). Flushing of hydrocarbons with water generated by dehydration of smectite in its conversion to illite (but this involves either solution of hydrocarbons or pushing large molecules through small pores). 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. 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 aren’t soluble). Transport in solution of CO 2 (but production of CO 2 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). Flushing of hydrocarbons with water generated by dehydration of smectite in its conversion to illite (but this involves either solution of hydrocarbons or pushing large molecules through small pores). 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. 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 aren’t soluble). Transport in solution of CO 2 (but production of CO 2 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). Flushing of hydrocarbons with water generated by dehydration of smectite in its conversion to illite (but this involves either solution of hydrocarbons or pushing large molecules through small pores). 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. 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 aren’t soluble). Transport in solution of CO 2 (but production of CO 2 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). Flushing of hydrocarbons with water generated by dehydration of smectite in its conversion to illite (but this involves either solution of hydrocarbons or pushing large molecules through small pores). 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. 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 aren’t soluble). Transport in solution of CO 2 (but production of CO 2 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). Flushing of hydrocarbons with water generated by dehydration of smectite in its conversion to illite (but this involves either solution of hydrocarbons or pushing large molecules through small pores). University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology
Selley 1998
VIII. Migration A.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) Selley & Sonnenberg (2015, Elements of Petroleum Geology 3nd edn) cite no literature later than 1985 before concluding “pressure-driven hydrocarbon movement with or without microfracturing is an important part of primary migration. 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. 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. University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology 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 (See G&S 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)! Chemical/dissolution explanation Mechanical/fracturing explanation
University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology Bjørlykke 2010 “Primary hydrocarbon generation... is to many people the last great mystery of petroleum geology” R.C. Selley (1998) Elements of Petroleum Geology (2nd edn)
University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology Bjørlykke 2010 “Primary hydrocarbon generation... is to many people the last great mystery of petroleum geology” R.C. Selley (1998) Elements of Petroleum Geology (2nd edn)
VIII. Migration A.Primary migration - passage of petroleum out of the source rock in which it was generated. “Primary hydrocarbon generation... is to many people the last great mystery of petroleum geology” R.C. Selley (1998, Elements of Petroleum Geology 2nd edn) “Pressure-driven hydrocarbon movement with or without microfracturing is an important part of primary migration.” Selley & Sonnenberg (2015, Elements of Petroleum Geology 3nd edn), citing no literature later than 1985 ! 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 avenues, 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 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 avenues, driven by buoyancy contrast between petroleum and water that otherwise fills porosity. Avenues: 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 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 avenues, driven by buoyancy contrast between petroleum and water that otherwise fills porosity. Avenues: 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 University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology
Spill Point Seal Rock (Mudstone) Reservoir Rock (Sandstone) Migration from ‘Kitchen’ 1) Early Generation 2) Late Generation Gas displaces all oil Gas beginning to displace oil Displaced oil accumulates Petroleum System From a U of OK course ppt file
University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology An example from Pakistan, from a U of OK course ppt file
University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology Spill Point Seal Rock (Mudstone) Reservoir Rock (Sandstone) Migration from ‘Kitchen’ 1) Early Generation 2) Late Generation Gas displaces all oil Gas beginning to displace oil Displaced oil accumulates Petroleum System From a U of OK course ppt file
University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology Petroleum System
University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology Selley 1998
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) 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 University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology
Gluyas & Swarbrick 2004, in a very North-Sea example
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 The end (of the petroleum, and the lecture). University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology
Light gray Times New Roman text White sans-serif Helvetica text University of Georgia Department of Geology GEOL 4320/6320 Petroleum Geology Title Bjørlykke 2010 Gluyas & Swarbrick 2004 Selley 1998 Sources Schlumberger Oilfielld Glossary Conaway 1999 Assaad 2008 Shepherd 2009 Shell Petroleum Handbook (1983) Rigzone Crain’s Petrophysical Handbook North 1980 AAPG Basic Well Log Analysis course notes Schlumberger Log Interpretation P&I Glover’s Petrophysique Asquith and Krygowski 2004 Baker-Hughes Atlas of Log Responses Notes Jonathan B. Martin UF class notes Wikipedia White sans-serif Helvetica text Tissot & Welte (1984)