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{{publication  

{{publication  

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  | image  = ST53Cover.jpg

  | width  = 120px

  | width  = 120px

  | series  = Studies in Geology

  | series  = Studies in Geology

  | isbn    = 0891810609

  | isbn    = 0891810609

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Folds are bends or flexures of layered rock that form in response to motion along [[fault]]s, [[diapirism]], [[compaction]], and regional subsidence or [[uplift]]. Folds are expressed in [[seismic reflection profile]]s as one or more regions of dipping reflections ([[dip]] domains) that correspond to inclined [[stratigraphic]] contacts.

Folds are bends or flexures of layered rock that form in response to motion along [[fault]]s, [[diapirism]], [[compaction]], and regional subsidence or [[uplift]]. Folds are expressed in [[seismic reflection profile]]s as one or more regions of dipping reflections ([[dip]] domains) that correspond to inclined [[stratigraphic]] contacts.

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File:ST53_Part01_Pg03A.jpg

File:ST53_Part01_Pg03A.jpg|{{figure number|1}}

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File:ST53_Part01_Pg03B.jpg|{{figure number|2}}

File:ST53_Part01_Pg04.jpg|Folds in seismic sections.

File:ST53_Part01_Pg04.jpg|{{figure number|3}}Folds in seismic sections.

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Folds are classified based on whether or not the thickness of stratigraphic layers changes in dip domains or across axial surfaces.

Folds are classified based on whether or not the thickness of stratigraphic layers changes in dip domains or across axial surfaces.

Parallel folds preserve layer thickness, and are common in strata that deformed predominantly by flexural slip (see inset at right). Axial surfaces bisect inter-limb angles in parallel folds.

Parallel folds preserve layer thickness, and are common in [[strata]] that deformed predominantly by [[flexural slip]] (see inset at right on [[:file:ST53_Part01_Pg05A.jpg|Figure 4]]). Axial surfaces bisect inter-limb angles in parallel folds.

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File:ST53_Part01_Pg05B.jpg|{{figure number|5}}

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Parallel folds commonly form by a deformation mechanism called flexural slip, where folding is accommodated by motions on minor faults that occur along some mechanical layering — usually bedding. Flexural-slip surfaces, which can be observed in core or outcrop, may vary in spacing from a few millimeters to several tens of meters in spacing.

Parallel folds commonly form by a [[deformation]] mechanism called flexural slip, where folding is accommodated by motions on minor [[fault]]s that occur along some mechanical layering&mdash;usually bedding. Flexural-slip surfaces, which can be observed in [[core]] or [[outcrop]], may vary in spacing from a few millimeters to several tens of meters in spacing.

==Shortcomings in seismic images of folds==

==Shortcomings in seismic images of folds==

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File:ST53_Part01_Pg06A.jpg|{{figure number|6}}

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File:ST53_Part01_Pg06B.jpg|{{figure number|7}}

 

 

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