Changes

==Periodic vs. episodic parasequences==

==Periodic vs. episodic parasequences==

[[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., 1990; 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., Sarg, J., F., Wright, F., M., 1995, [[Sequence stratigraphy]] and reservoir delineation of the middle Pennsylvanian (Desmoinesian), Paradox basin and Aneth field, southwestern U., S., A., in Read, J., F., Weber, L., J., Sarg, J., F., Wright, F., M., 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 tidal flat migration or 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., Sarg, J., F., Wright, F., M., 1995, [[Sequence stratigraphy]] and reservoir delineation of the middle Pennsylvanian (Desmoinesian), Paradox basin and Aneth field, southwestern U., S., A., in Read, J., F., Weber, L., J., Sarg, J., F., Wright, F., M., 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 tidal flat migration or 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 set is a succession of genetically related parasequences that forms a distinctive stacking pattern. A parasequence set is generally bounded by a marine flooding surface.<ref name=ch21r45 />

A parasequence set is a succession of genetically related parasequences that forms a distinctive stacking pattern. A parasequence set is generally bounded by a marine flooding surface.<ref name=ch21r45 />

[[file:exploring-for-stratigraphic-traps_fig21-13.png|300px|thumb|{{figure number|2}}Characteristics of two upward-fining parasequences formed in a tidal flat to subtidal environment. From Van Wagoner et al., 1990; courtesy AAPG.]]

[[file:exploring-for-stratigraphic-traps_fig21-13.png|300px|thumb|{{figure number|2}}Characteristics of two upward-fining parasequences formed in a tidal flat to subtidal environment. From Van Wagoner et al.;<ref name=ch21r47 /> courtesy AAPG.]]

==Upward-coarsening parasequence==

==Upward-coarsening parasequence==