Geologia
Páginas: 2 (355 palabras)
Publicado: 21 de abril de 2012
La presencia de este pliegue es un misterio para muchos. Se podría explicar por la presencia de fallas y diques en la zona, pero lo extraño es que es prácticamente el único de la formación LaHerradura. De haber influido estos factores, existirían muchos otros, por lo que su origen sigue siendo un tanto misterioso. Morro Solar, Lima, Perú.
Fault-bend folds are a consequence of décollementtectonics where bedding parallel detachments climb section by cutting across several beds. A model of fault-bend folding is shown in figure 28-5 where the thrust plane comes from the right, cuts upwardacross bedding, and continues parallel with bedding off to the left. Upon the initiation of the fault across bedding two kink bands develop at the bends in the footwall because these bends cause foldingin the upper sheet of the thrust system. The axial surfaces A and B terminate a the bends in the detachment where it changes from bedding parallel to cross cutting. The axial surfaces A' and B'terminate at the transitions between crosscutting and bedding-plane fault segments in the hanging wall at points X' and Y' which match points X and Y in the footwall. As slip continues kink bands A-A'and B-B' grow in with and the anticline above the crosscutting fault grows in height. Axial surfaces A' and B' move with the thrust sheet because they are fixed to the hanging wall cutoffs. Becausethe axial surfaces A and B are fixed to the footwall cutoffs X and Y, the beds must move through the axial surfaces, first bending and then unbending.
The motion of the fault-bend fold is complexbecause when the hanging-wall cutoff, Y', reaches the footwall cutoff, X, the fold has reached its maximum amplitude, which is the height of the step in décollement. At this point the deformation, axialsurface A, which has been fixed to the footwall is suddenly released to move with the hanging-wall cutoff, Y', whereas axial surface B', which has been moving with the hanging wall , is suddenly...
Fault-bend folds are a consequence of décollementtectonics where bedding parallel detachments climb section by cutting across several beds. A model of fault-bend folding is shown in figure 28-5 where the thrust plane comes from the right, cuts upwardacross bedding, and continues parallel with bedding off to the left. Upon the initiation of the fault across bedding two kink bands develop at the bends in the footwall because these bends cause foldingin the upper sheet of the thrust system. The axial surfaces A and B terminate a the bends in the detachment where it changes from bedding parallel to cross cutting. The axial surfaces A' and B'terminate at the transitions between crosscutting and bedding-plane fault segments in the hanging wall at points X' and Y' which match points X and Y in the footwall. As slip continues kink bands A-A'and B-B' grow in with and the anticline above the crosscutting fault grows in height. Axial surfaces A' and B' move with the thrust sheet because they are fixed to the hanging wall cutoffs. Becausethe axial surfaces A and B are fixed to the footwall cutoffs X and Y, the beds must move through the axial surfaces, first bending and then unbending.
The motion of the fault-bend fold is complexbecause when the hanging-wall cutoff, Y', reaches the footwall cutoff, X, the fold has reached its maximum amplitude, which is the height of the step in décollement. At this point the deformation, axialsurface A, which has been fixed to the footwall is suddenly released to move with the hanging-wall cutoff, Y', whereas axial surface B', which has been moving with the hanging wall , is suddenly...
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