Changes

In the case where sedimentation rate exceeds uplift rate ([[:file:ST53Part01Pg12A.jpg|Figure 3, center]]), strata are folded through the synclinal axis and incorporated into the widening fold limb. The dip of folded growth strata is equal to dip of the fold limb in pre-growth strata. The width of the dip panel for each growth horizon corresponds to the amount of fold growth that occurred subsequent to the deposition of that marker. As a result, younger horizons have narrower fold limbs than do older horizons, forming narrowing upward fold limbs or kink bands in growth strata (growth triangles). In the case where uplift rate exceeds sedimentation rate ([[:file:ST53Part01Pg12A.jpg|Figure 3, right side]]), each increment of folding produces a discrete fold scarp located where the active axial surface projects to the Earth’s surface.<ref name=Shawetal_2004>Shaw, J. H., E. Novoa, and C. Connors, 2004, [http://archives.datapages.com/data/specpubs/memoir82/CHAPTER20/CHAPTER20.HTM Structural controls on growth stratigraphy in contractional fault-related folds], ''in'' K. R. McClay, ed., Thrust tectonics and hydrocarbon systems: [http://archives.datapages.com/data/alt-browse/aapg-special-volumes/m82.htm AAPG Memoir 82], p. 400-412.</ref> Subsequent deposits onlap the fold scarp, producing stratigraphic pinchouts above the fold limb. Fold scarps and stratigraphic pinch-outs are displaced laterally and folded as they are incorporated into widening limbs.

In the case where sedimentation rate exceeds uplift rate ([[:file:ST53Part01Pg12A.jpg|Figure 3, center]]), strata are folded through the synclinal axis and incorporated into the widening fold limb. The dip of folded growth strata is equal to dip of the fold limb in pre-growth strata. The width of the dip panel for each growth horizon corresponds to the amount of fold growth that occurred subsequent to the deposition of that marker. As a result, younger horizons have narrower fold limbs than do older horizons, forming narrowing upward fold limbs or kink bands in growth strata (growth triangles). In the case where uplift rate exceeds sedimentation rate ([[:file:ST53Part01Pg12A.jpg|Figure 3, right side]]), each increment of folding produces a discrete fold scarp located where the active axial surface projects to the Earth’s surface.<ref name=Shawetal_2004>Shaw, J. H., E. Novoa, and C. Connors, 2004, [http://archives.datapages.com/data/specpubs/memoir82/CHAPTER20/CHAPTER20.HTM Structural controls on growth stratigraphy in contractional fault-related folds], ''in'' K. R. McClay, ed., Thrust tectonics and hydrocarbon systems: [http://archives.datapages.com/data/alt-browse/aapg-special-volumes/m82.htm AAPG Memoir 82], p. 400-412.</ref> Subsequent deposits onlap the fold scarp, producing stratigraphic pinchouts above the fold limb. Fold scarps and stratigraphic pinch-outs are displaced laterally and folded as they are incorporated into widening limbs.

Contractional fault-related folding theories that exclusively invoke kink-band migration include fault-bend folding,<ref name=Suppe_1983 /> constant-thickness and fixed axis fault-propagation folding,<ref name=Suppeandmedwedeff_1990 /> and basement-involved (triple junction) folding.<ref name=Narrandsuppe_1994>Narr, W., and J. Suppe, 1994, Kinematics of basement-involved compressive structures: American Journal of Science, v. 294, p. 802-860.</ref>

Contractional fault-related folding theories that exclusively invoke kink-band migration include fault-bend folding,<ref name=Suppe_1983 /> constant-thickness and fixed axis fault-propagation folding,<ref name=Suppeandmedwedeff_1990 /> and [[basement]]-involved (triple junction) folding.<ref name=Narrandsuppe_1994>Narr, W., and J. Suppe, 1994, Kinematics of basement-involved compressive structures: American Journal of Science, v. 294, p. 802-860.</ref>

[[File:ST53Part01Pg12B.jpg|thumb|300px|{{figure number|4}}]]

[[File:ST53Part01Pg12B.jpg|thumb|300px|{{figure number|4}}]]

[[File:ST53Part01Pg14A.jpg|thumb|300px|{{figure number|6}}]]

[[File:ST53Part01Pg14A.jpg|thumb|300px|{{figure number|6}}]]

In [[:file:ST53Part01Pg14A.jpg|Figure 6]], the top model shows a post-tectonic drape sequence above a rigid basement high. The drape sequence thins toward the crest of the structure, with younger strata having less relief than older units. The lower model in [[:file:ST53Part01Pg14A.jpg|Figure 6]] shows growth strata above a fold developed by progressive limb rotation. The two stratigraphic patterns are similar, and in some cases difficult to distinguish. Incorrect interpretations of drape and growth sequences can lead to flawed estimates of structural timing and kinematics. Thus, care should be taken in trying to distinguish between drape and growth sequences.

In [[:file:ST53Part01Pg14A.jpg|Figure 6]], the top model shows a post-tectonic drape sequence above a rigid [[basement]] high. The drape sequence thins toward the crest of the structure, with younger strata having less relief than older units. The lower model in [[:file:ST53Part01Pg14A.jpg|Figure 6]] shows growth strata above a fold developed by progressive limb rotation. The two stratigraphic patterns are similar, and in some cases difficult to distinguish. Incorrect interpretations of drape and growth sequences can lead to flawed estimates of structural timing and kinematics. Thus, care should be taken in trying to distinguish between drape and growth sequences.

[[File:ST53Part01Pg14B.jpg|thumb|300px|{{figure number|7}}]]

[[File:ST53Part01Pg14B.jpg|thumb|300px|{{figure number|7}}]]