10,323
edits
Changes
Jump to navigation
Jump to search
Line 68:
Line 68: − [[file:AlHawajAlQahtaniFigure5.jpg|thumb|300px|{{figure number|5}}Schematic 3D geometry of salt structures rising from a) line sources and b) point sources. Note the complexity in all directions resulting from salt deformation.<ref name=HudecandJackson_2007>Hudec, M. R., & Jackson, M. P. (2007). Terra infirma: Understanding salt tectonics. Earth-Science Reviews, 82(1-2), 1-28.</ref>]]+ − * Salt tectonics: The underlying cause for the complexity in deformation in salt basins is that salt rock can flow in different directions that are not necessarily perpendicular to the basin margin when subjected to burial, compaction and margin tilt ([[:file:AlHawajAlQahtaniFigure5.jpg|Figure 5]]).<ref name=Fossen_2016>Fossen, H. (2016). Structural geology. Cambridge university press.</ref> When such flow is out-of-plane with respect to a cross section, performing 2D balancing would most likely not yield conserved cross-sectional areas of the salt and, therefore, restoration may not be adequate. This necessitates the use of 3D restoration to better restore deformation in salt basins in the regional scale and validate the results of the 2D restoration.<ref name=Rowanandratliff_2012>Rowan, M. G., & Ratliff, R. A. (2012). Cross-section restoration of salt-related deformation: Best practices and potential pitfalls. Journal of Structural Geology, 41, 24-37.</ref> − [[file:AlHawajAlQahtaniFigure6.jpg|thumb|300px|{{figure number|6}}Examples from the deep-water Niger Delta of using channel geometry to constrain strike-slip displacement.<ref name=Durandriardetal_2013>Durand-Riard, P., Shaw, J. H., Plesch, A., & Lufadeju, G. (2013). Enabling 3D geomechanical restoration of strike-and oblique-slip faults using geological constraints, with applications to the deep-water Niger Delta. Journal of Structural Geology, 48, 33-44.</ref> A) Faulted horizon surface. The small black box is the location of B-E. B-D) Channels lateral geometry on different horizon levels. E) Restoration using the channels geometry to constrain strike-slip displacement. F) Faulted horizon surface. The small black box is the location of G & H. G) Channels lateral geometry on different horizon levels. H) Restored state.]]+ + + + + + − * Strike-slip tectonics: The out-of-plane transport direction also affects the 2D restoration of areas affected by strike-slip faults. Furthermore, the limited dip-slip component in most strike-slip faults means that flattening of younger strata to estimate displacement and perform the restoration will most likely not yield fully restored sections/volumes.<ref name=Durandriardetal_2013 /> Hence, it is advised that features that have certain spatial geometry (e.g. channels, older faults) and are cut by the strike-slip fault be used to put constraint on the horizontal displacement. [[:file:AlHawajAlQahtaniFigure6.jpg|Figure 6]] shows an example from the deep-water Niger Delta where 3D geomechanical restoration of strike-slip faults was enabled by utilizing such lateral constraints.<ref name=Peach_1907 />+ +
no edit summary
The impact of structural restoration on petroleum exploration and development resides in its ability to evaluate the relative timing of petroleum system elements and processes. In particular, structural restoration constrains the timing of these elements, which helps to de-risk them when evaluating a prospect. Of particular importance is the timing of the trap formation that can be evaluated using structural restoration and compared to the timing of the hydrocarbon expulsion and migration. For example, [[:file:AlHawajAlQahtaniFigure4.jpg|Figure 4]] shows 2D geological evolution at the Monagas Fold and Thrust Belt in Venezuela, demonstrating the temporal relationship between trap formation and source rock maturation and hydrocarbon expulsion, migration, and accumulation in a structurally complex basin.<ref name=Neumaier_2016 />
The impact of structural restoration on petroleum exploration and development resides in its ability to evaluate the relative timing of petroleum system elements and processes. In particular, structural restoration constrains the timing of these elements, which helps to de-risk them when evaluating a prospect. Of particular importance is the timing of the trap formation that can be evaluated using structural restoration and compared to the timing of the hydrocarbon expulsion and migration. For example, [[:file:AlHawajAlQahtaniFigure4.jpg|Figure 4]] shows 2D geological evolution at the Monagas Fold and Thrust Belt in Venezuela, demonstrating the temporal relationship between trap formation and source rock maturation and hydrocarbon expulsion, migration, and accumulation in a structurally complex basin.<ref name=Neumaier_2016 />
==Challenges==
==Challenges==
One of the main challenges encountered during restoration is the three-dimensional nature of geology, which means that out-of-plane deformation may not be captured by the conventional 2D section restoration. This is most obvious when trying to restore salt basins or blocks affected by strike-slip deformation.
One of the main challenges encountered during restoration is the three-dimensional nature of geology, which means that out-of-plane deformation may not be captured by the conventional 2D section restoration. This is most obvious when trying to restore salt basins or blocks affected by strike-slip deformation.
<gallery mode=packed style=center heights=400px>
file:AlHawajAlQahtaniFigure5.jpg|{{figure number|5}}Schematic 3D geometry of salt structures rising from a) line sources and b) point sources. Note the complexity in all directions resulting from salt deformation.<ref name=HudecandJackson_2007>Hudec, M. R., and M. P. Jackson, 2007, Terra infirma: Understanding salt tectonics: Earth-Science Reviews, v. 82, no. 1-2, p. 1-28.</ref>]]
file:AlHawajAlQahtaniFigure6.jpg|{{figure number|6}}Examples from the deep-water Niger Delta of using channel geometry to constrain strike-slip displacement.<ref name=Durandriardetal_2013>Durand-Riard, P., J. H. Shaw, A., Plesch, and G. Lufadeju, 2013, Enabling 3-D geomechanical restoration of strike-and oblique-slip faults using geological constraints, with applications to the deep-water Niger Delta: Journal of Structural Geology, v. 48, p. 33-44.</ref> A) Faulted horizon surface. The small black box is the location of B-E. B-D) Channels lateral geometry on different horizon levels. E) Restoration using the channels geometry to constrain strike-slip displacement. F) Faulted horizon surface. The small black box is the location of G & H. G) Channels lateral geometry on different horizon levels. H) Restored state.]]
===Salt tectonics===
The underlying cause for the complexity in deformation in salt basins is that salt rock can flow in different directions that are not necessarily perpendicular to the basin margin when subjected to burial, compaction and margin tilt ([[:file:AlHawajAlQahtaniFigure5.jpg|Figure 5]]).<ref name=Fossen_2016>Fossen, H. (2016). Structural geology. Cambridge university press.</ref> When such flow is out-of-plane with respect to a cross section, performing 2D balancing would most likely not yield conserved cross-sectional areas of the salt and, therefore, restoration may not be adequate. This necessitates the use of 3D restoration to better restore deformation in salt basins in the regional scale and validate the results of the 2-D restoration.<ref name=Rowanandratliff_2012>Rowan, M. G., & Ratliff, R. A. (2012). Cross-section restoration of salt-related deformation: Best practices and potential pitfalls. Journal of Structural Geology, 41, 24-37.</ref>
===Strike-slip tectonics===
The out-of-plane transport direction also affects the 2D restoration of areas affected by strike-slip faults. Furthermore, the limited dip-slip component in most strike-slip faults means that flattening of younger strata to estimate displacement and perform the restoration will most likely not yield fully restored sections/volumes.<ref name=Durandriardetal_2013 /> Hence, it is advised that features that have certain spatial geometry (e.g. channels, older faults) and are cut by the strike-slip fault be used to put constraint on the horizontal displacement. [[:file:AlHawajAlQahtaniFigure6.jpg|Figure 6]] shows an example from the deep-water Niger Delta where 3D geomechanical restoration of strike-slip faults was enabled by utilizing such lateral constraints.<ref name=Peach_1907 />
==See also==
==See also==