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[[file:exploring-for-stratigraphic-traps_fig21-12.png|300px|thumb|{{figure number|1}}Characteristics of an upward-coarsening parasequence formed in a deltaic environment. From Van Wagoner et al.;<ref name=ch21r47 /> courtesy AAPG.]]

[[file:exploring-for-stratigraphic-traps_fig21-12.png|300px|thumb|{{figure number|1}}Characteristics of an upward-coarsening parasequence formed in a deltaic environment. From Van Wagoner et al.;<ref name=ch21r47 /> courtesy AAPG.]]

A parasequence can be either periodic or episodic.<ref name=ch21r48>Weber, L. J., J. F. Sarg, and F. M. Wright, 1995, [[Sequence stratigraphy]] and reservoir delineation of the middle Pennsylvanian (Desmoinesian), Paradox basin and Aneth field, southwestern USA, in J. F. Read, L. J. Weber, J. F. Sarg, and F. M. Wright, eds., Milankovitch Sea-Level Changes, Cycles, and Reservoirs on Carbonate Platforms in Greenhouse and Ice-House Worlds: SEPM Short Course No. 35, 79 p.</ref> A '''periodic parasequence''' has regional continuity and forms in response to deposition during a global sea level cycle. An '''episodic parasequence''' has limited lateral extent and forms in response to (for example) [[tidal flat]] migration or [[Deltaic environments|delta]] lobe shifts. Episodic parasequences are of very short duration—generally less than 10,000 years. Periodic parasequences have average durations of 100,000 years.

A parasequence can be either periodic or episodic.<ref name=ch21r48>Weber, L. J., J. F. Sarg, and F. M. Wright, 1995, [[Sequence stratigraphy]] and reservoir delineation of the middle Pennsylvanian (Desmoinesian), Paradox basin and Aneth field, southwestern USA, in J. F. Read, L. J. Weber, J. F. Sarg, and F. M. Wright, eds., Milankovitch Sea-Level Changes, Cycles, and Reservoirs on Carbonate Platforms in Greenhouse and Ice-House Worlds: SEPM Short Course No. 35, 79 p.</ref> A '''periodic parasequence''' has regional continuity and forms in response to deposition during a global sea level cycle. An '''episodic parasequence''' has limited [[lateral]] extent and forms in response to (for example) [[tidal flat]] migration or [[Deltaic environments|delta]] lobe shifts. Episodic parasequences are of very short duration—generally less than 10,000 years. Periodic parasequences have average durations of 100,000 years.

==Parasequence sets==

==Parasequence sets==