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| * Prograding—caused by lateral accretion of strata | | * Prograding—caused by lateral accretion of strata |
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− | [[file:exploring-for-stratigraphic-traps_fig21-24.png|thumb|{{figure number|1}}.]] | + | [[file:exploring-for-stratigraphic-traps_fig21-24.png|left|thumb|{{figure number|1}}.]] |
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| ==Parallel reflector patterns== | | ==Parallel reflector patterns== |
| Parallel reflections include subparallel, wavy, and divergent. Parallel, subparallel, and wavy reflectors suggest uniform depositional rates on a uniformly subsiding surface, such as a shelf or basin plain. Divergent reflectors suggest lateral variations in depositional rates or progressive tilting of a depositional surface. [[:file:exploring-for-stratigraphic-traps_fig21-24.png|Figure 1]] shows reflection configurations for this group. | | Parallel reflections include subparallel, wavy, and divergent. Parallel, subparallel, and wavy reflectors suggest uniform depositional rates on a uniformly subsiding surface, such as a shelf or basin plain. Divergent reflectors suggest lateral variations in depositional rates or progressive tilting of a depositional surface. [[:file:exploring-for-stratigraphic-traps_fig21-24.png|Figure 1]] shows reflection configurations for this group. |
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| + | [[file:exploring-for-stratigraphic-traps_fig21-25.png|thumb|{{figure number|2}}After .<ref name=ch21r31>Mitchum, R., M., Vail, P., R., Sangree, J., B., 1977, Seismic stratigraphy and global changes in sea level, part 6: stratigraphic interpretations of seismic reflection patterns in depositional sequences, in Payton, C., E., ed., Seismic Stratigraphy and [[Applications]] to Hydrocarbon Exploration: AAPG Memoir 26, p. 117–133.</ref>]] |
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| ==Discontinuous reflector patterns== | | ==Discontinuous reflector patterns== |
| Five types of discontinuous reflector patterns that help interdepositional systems are shown in the figure below. Hummocky strata may be discontinuous point bars and crevasse splays. Chaotic reflectors suggest coarse-grained fluvial or turbidite channel fills. Contorted features may be shale-prone debris flows. Precise identification of depositional environments requires integration with other data. | | Five types of discontinuous reflector patterns that help interdepositional systems are shown in the figure below. Hummocky strata may be discontinuous point bars and crevasse splays. Chaotic reflectors suggest coarse-grained fluvial or turbidite channel fills. Contorted features may be shale-prone debris flows. Precise identification of depositional environments requires integration with other data. |
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− | [[file:exploring-for-stratigraphic-traps_fig21-25.png|thumb|{{figure number|21-25}}After .<ref name=ch21r31>Mitchum, R., M., Vail, P., R., Sangree, J., B., 1977, Seismic stratigraphy and global changes in sea level, part 6: stratigraphic interpretations of seismic reflection patterns in depositional sequences, in Payton, C., E., ed., Seismic Stratigraphy and [[Applications]] to Hydrocarbon Exploration: AAPG Memoir 26, p. 117–133.</ref>]]
| + | [[file:exploring-for-stratigraphic-traps_fig21-26.png|thumb|{{figure number|3}}After .<ref name=ch21r31 />]] |
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− | [[file:exploring-for-stratigraphic-traps_fig21-26.png|thumb|{{figure number|2}}After .<ref name=ch21r31 />]] | |
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| ==Prograding reflector patterns== | | ==Prograding reflector patterns== |
− | One of the most common depositional features observed in seismic sections are clinoforms manifested in a configuration pattern called ''offlap''. Clinoforms are progradational strata that form through the progressive development of gently sloping surfaces. Paleowater depths can be interpreted from the height of prograding clinoforms. [[:file:exploring-for-stratigraphic-traps_fig21-26.png|Figure 2]] shows prograding reflectors and their possible depositional significance. | + | One of the most common depositional features observed in seismic sections are clinoforms manifested in a configuration pattern called ''offlap''. Clinoforms are progradational strata that form through the progressive development of gently sloping surfaces. Paleowater depths can be interpreted from the height of prograding clinoforms. [[:file:exploring-for-stratigraphic-traps_fig21-26.png|Figure 3]] shows prograding reflectors and their possible depositional significance. |
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− | [[file:exploring-for-stratigraphic-traps_fig21-27.png|thumb|{{figure number|3}}.]] | + | [[file:exploring-for-stratigraphic-traps_fig21-27.png|thumb|{{figure number|4}}.]] |
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| ==Channel fill patterns== | | ==Channel fill patterns== |
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− | Channels are expressed in seismic sections as negative relief features truncating the underlying strata. Fill patterns are shown in [[:file:exploring-for-stratigraphic-traps_fig21-27.png|Figure 3]]. | + | Channels are expressed in seismic sections as negative relief features truncating the underlying strata. Fill patterns are shown in [[:file:exploring-for-stratigraphic-traps_fig21-27.png|Figure 4]]. |
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| ==See also== | | ==See also== |