A parasequence is a fundamental concept of sequence stratigraphy. Parasequences are not directly related to sequences.
Definition
editA parasequence is defined as a genetically related succession of bedsets that is bounded by marine flooding surfaces (or their correlative surfaces) on top and at the bottom.[1] The succession is supposed to be relatively conformable in the sense that breaks in deposition within the parasequence are much shorter than the time of deposition of the parasequence itself.[2][1] Most parasequences show a shallowing upward,[3] which is sometimes also included into the definition.[4]
Properties
editSince parasequences are relatively conformable, so Walther's law applies within a parasequence. This is not necessarily the case for transitions from one parasequence to another. They are also typically of the size of one up to tens of meters.[3]
References
edit- ^ a b Van Wagoner, JC (1988). "An overview of the fundamentals of sequence stratigraphy and key definitions". Special Publications of SEPM.
{{cite journal}}: Cite journal requires|journal=(help) - ^ Patzkowsky, Mark E.; Holland, Steven M. (2012). Stratigraphic Paleobiology. Chicago: University of Chicago University Press. p. 34.
- ^ a b Patzkowsky, Mark E.; Holland, Steven M. (2012). Stratigraphic Paleobiology. Chicago: University of Chicago University Press. p. 35.
- ^ Catuneanu, Octavian (2011). "Sequence stratigraphy: methodology and nomenclature" (PDF). Newsletters on Stratigraphy. 44 (3). E. Schweizerbart'sche Verlagsbuchhandlung: 173–245. doi:10.1127/0078-0421/2011/0011.