Changes

  | part    = Critical elements of the petroleum system

  | part    = Critical elements of the petroleum system

  | chapter = Sedimentary basin analysis

  | chapter = Sedimentary basin analysis

  | frompg  = 4-1

  | frompg  = 4-14

  | topg    = 4-123

  | topg    = 4-15

  | author  = John M. Armentrout

  | author  = John M. Armentrout

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch04/ch04.htm

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch04/ch04.htm

  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

}}

}}

Tectonic maps of a basin and surrounding areas, in combination with regional structure cross sections, give an overall impression of the geologic architecture of the basin and form the base from which other interpretations are made. A large-scale map shows the depth to the basement in the basin and the distribution of crustal types. Always be sure important tectonic elements are shown, such as specific fold belts and major faults.

Tectonic maps of a basin and surrounding areas, in combination with regional structure [[cross section]]s, give an overall impression of the geologic architecture of the basin and form the base from which other interpretations are made. A large-scale map shows the depth to the [[basement]] in the basin and the distribution of crustal types. Always be sure important tectonic elements are shown, such as specific [[fold]] belts and major faults.

==Tectonic map==

==Tectonic map==

[[:file:sedimentary-basin-analysis_fig4-6.png|Figure 1]] is a tectonic map of the Gulf of Mexico (GOM; see [http://www.epa.gov/gmpo/about/facts.html General facts about the Gulf of Mexico]) basin. It shows the following:

[[:file:sedimentary-basin-analysis_fig4-6.png|Figure 1]] is a tectonic map of the [[Gulf of Mexico]] (GOM; see [http://www.epa.gov/gmpo/about/facts.html General facts about the Gulf of Mexico]) basin. It shows the following:

* Generalized depth to basement (approximately the base of Jurassic sedimentary rock)

* Generalized depth to basement (approximately the base of Jurassic sedimentary rock)

* Distribution of four crustal types—continental, thick transitional, thin transitional, and oceanic

* Distribution of four crustal types—[[Continental crust|continental]], [[Transitional crust|thick transitional]], [[Transitional crust|thin transitional]], and [[Oceanic crust|oceanic]]

* Known distribution of mid-Jurassic evaporites (pre-marine evaporites)

* Known distribution of mid-Jurassic [[evaporite]]s (pre-marine evaporites)

* Several major structural features

* Several major structural features

The thickest sediments occur over the thin transitional crust, which has subsided beneath the load of more than [[distance::14 km]] (>45,000 ft) of sedimentary rock. (For additional discussion of the structural framework, see Jones and Freed.<ref name=ch04r50>Jones, J. O., and R. L. Freed, eds., 1996, Structural Framework of the Northern Gulf of Mexico: Gulf Coast Association of Geological Sciences, 112 p.</ref>)

The thickest sediments occur over the thin transitional [[crust]], which has subsided beneath the load of more than [[distance::14 km]] (>45,000 ft) of sedimentary rock. (For additional discussion of the structural framework, see Jones and Freed.<ref name=ch04r50>Jones, J. O., and R. L. Freed, eds., 1996, Structural Framework of the Northern Gulf of Mexico: Gulf Coast Association of Geological Sciences, 112 p.</ref>)

==Salt tectonic map==

==Salt tectonic map==

<gallery>

<gallery mode=packed heights=200px widths=200px>

file:sedimentary-basin-analysis_fig4-6.png|{{figure number|1}}Tectonic map of the Gulf of Mexico. Modified from Buffler.<ref name=Buffler_1991>Buffler, R. T., 1991, Early evolution of the Gulf of Mexico basin, ''in'' D. Goldthwaite, ed., An introduction to Central Gulf Coast geology: New Orleans Geological Society, p. 1-16.</ref> Courtesy New Orleans Geological Society.

sedimentary-basin-analysis_fig4-6.png|{{figure number|1}}Tectonic map of the Gulf of Mexico. Modified from Buffler.<ref name=Buffler_1991>Buffler, R. T., 1991, Early evolution of the Gulf of Mexico basin, ''in'' D. Goldthwaite, ed., An introduction to Central Gulf Coast geology: New Orleans Geological Society, p. 1-16.</ref> Courtesy New Orleans Geological Society.

file:sedimentary-basin-analysis_fig4-41.png|{{figure number|2}}Depositional strike seismic reflection profile across a valley.

sedimentary-basin-analysis_fig4-41.png|{{figure number|2}}Depositional strike seismic reflection profile across a valley.

file:sedimentary-basin-analysis_fig4-54.png|{{figure number|3}}Regional cross section summarizing the regional hydraulic flow regimes of the Louisiana Gulf Coast above a depth of 20,000 ft (6096 m). From Hanor and Sassen.<ref name=Hanorandsassen_1990>Hanor, J. S., and R. Sassen, 1990 Evidence for large-scale vertical and lateral migration of formation waters, dissolved salt, and crude oil in the Louisiana Gulf Coast: Proceedings, Gulf Coast Section SEPM 9th Annual Research Conference, p. 283-296.</ref> Courtesy Gulf Coast SEPM.

sedimentary-basin-analysis_fig4-54.png|{{figure number|3}}Regional cross section summarizing the regional hydraulic flow regimes of the Louisiana Gulf Coast above a depth of 20,000 ft (6096 m). From Hanor and Sassen.<ref name=Hanorandsassen_1990>Hanor, J. S., and R. Sassen, 1990 Evidence for large-scale vertical and lateral migration of formation waters, dissolved salt, and [[crude oil]] in the Louisiana Gulf Coast: Proceedings, Gulf Coast Section SEPM 9th Annual Research Conference, p. 283-296.</ref> Courtesy Gulf Coast SEPM.

file:sedimentary-basin-analysis_fig4-55.png|{{figure number|4}}North–south 3-D seismic reflection profile illustrating three possible hydrocarbon migration pathways and related sea-bed features. Based on data from Lovely and Ruggiero.<ref name=Lovely&RuggieroPC>Lovely and Ruggiero, 1995, personal communication</ref>

sedimentary-basin-analysis_fig4-55.png|{{figure number|4}}North–south 3-D seismic reflection profile illustrating three possible hydrocarbon migration pathways and related sea-bed features. Based on data from Lovely and Ruggiero.<ref name=Lovely&RuggieroPC>Lovely and Ruggiero, 1995, personal communication</ref>

file:sedimentary-basin-analysis_fig4-7.png|{{figure number|5}}Salt structures in the northwestern Gulf of Mexico and adjacent interior basins. Modified from Jackson and Galloway.<ref name=JacksonandGalloway_1984>Jackson, M. P. A., and W. E. Galloway, 1984, [http://archives.datapages.com/data/alt-browse/aapg-special-volumes/cn25.htm Structural and depositional styles of Gulf Coast Tertiary continental margins: Applications to hydrocarbon exploration]: AAPG Continuing Education Course Notes Series 25, 226 p.</ref>

sedimentary-basin-analysis_fig4-7.png|{{figure number|5}}Salt structures in the northwestern Gulf of Mexico and adjacent interior basins. Modified from Jackson and Galloway.<ref name=JacksonandGalloway_1984>Jackson, M. P. A., and W. E. Galloway, 1984, [http://archives.datapages.com/data/alt-browse/aapg-special-volumes/cn25.htm Structural and depositional styles of Gulf Coast Tertiary continental margins: Applications to hydrocarbon exploration]: AAPG Continuing Education Course Notes Series 25, 226 p.</ref>

</gallery>

</gallery>

The stratigraphic and tectonic history of the GOM basin is strongly affected by salt tectonics. As a consequence of differential loading of salt by sediment sourced from the North American craton, the distribution of salt-cored structures is oldest in the onshore northern margin of the basin where Late Cretaceous and early Cenozoic progradation resulted in salt-structure growth.

The stratigraphic and tectonic history of the GOM basin is strongly affected by salt tectonics. As a consequence of differential loading of salt by sediment sourced from the North American craton (see [[Great American carbonate bank]], the distribution of salt-cored structures is oldest in the onshore northern margin of the basin where Late Cretaceous and early [[Cenozoic]] [[Depocenter#Sediment_supply_rate_and_facies_patterns|progradation]] resulted in salt-structure growth.

Offshore beneath GOM waters, evacuation of salt structures is oldest in the north and is progressively younger toward the south. However, there are Late Jurassic and Early Cretaceous salt-cored structures along the Sigsbee Escarpment. Pliocene and Pleistocene depositional loading has displaced salt basinward and differentially loaded detached salt sills into salt-cored massifs and salt-cored diapirs.

Offshore beneath GOM waters, evacuation of salt structures is oldest in the north and is progressively younger toward the south. However, there are Late Jurassic and Early Cretaceous salt-cored structures along the Sigsbee Escarpment. Pliocene and Pleistocene depositional loading has displaced salt basinward and differentially loaded detached salt sills into salt-cored massifs and salt-cored diapirs.

==See also==

==See also==

 

* [[Making regional structural cross sections]]

* [[Making regional structural cross sections]]

* [[Determining plate tectonic setting and history]]

* [[Determining plate tectonic setting and history]]

* [[Determining tectonostratigraphic history]]

* [[Determining tectonostratigraphic history]]

* [[Using a tectonic history model for petroleum system analysis]]

* [[Using a tectonic history model for petroleum system analysis]]

==References==

==References==

[[Category:Critical elements of the petroleum system]]  

[[Category:Critical elements of the petroleum system]]  

[[Category:Sedimentary basin analysis]]

[[Category:Sedimentary basin analysis]]