unconformity

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Related to unconformities: correlation

un·con·for·mi·ty

 (ŭn′kən-fôr′mĭ-tē)
n. pl. un·con·for·mi·ties
1. Lack of conformity; nonconformity.
2. Geology A surface between successive strata representing a missing interval in the geologic record of time, and produced either by an interruption in deposition or by the erosion of depositionally continuous strata followed by renewed deposition.

unconformity

(ˌʌnkənˈfɔːmɪtɪ)
n, pl -ties
1. lack of conformity
2. (Geological Science) the contact surface between younger and older rocks representing a discontinuity in the geological record. Most commonly it represents an erosional surface

un•con•form•i•ty

(ˌʌn kənˈfɔr mɪ ti)

n., pl. -ties.
1. lack of conformity; incongruity; inconsistency.
2. Geol. a discontinuity in a stratigraphic sequence.
[1590–1600]

unconformity

A level where sedimentary rocks cover an older rock surface partly removed by erosion. The level marks a time gap.
References in periodicals archive ?
With Tertiary and Upper Cretaceous shales forming the major source rocks, much of the oil must have leaked across unconformities into geologically older strata.
The space agency said that the image, which shows a cluster of steeply inclined light-toned layers bounded above and below by "unconformities," is indicative of a "break" during which erosion of pre-existing layers was taking place at a higher rate than deposition of new materials.
The individual string-beads-like seismic reflection has been interpreted as the evidences of "epigenic karst system" in the Tarim Basin in the published papers, which is always linked with the terms "unconformities, weathering crusts, exposure, etc." (Guo et al.
The authors describe the characteristics of unconformities, which are discontinuities in a pile of sedimentary rocks that have resulted from temporary nondeposition of sediment, erosion of previously deposited sediment, changes in the rate of sedimentation, changes in the composition of sediment being deposited, or combinations of those factors.
This is suggested by tens of metres-thick, unconformable conglomeratic levels evidencing unconformities that are located at the base of the sparsely distributed remains of Carboniferous, Permian and Triassic successions that are well-dated (Cassinis et al., 2000 and references therein; Cassinis and Ronchi, 2002; Ronchi et al., 2008).
In his essay, the curator of the exhibition J.D.Talasek discusses engravings of unconformities, in particular John Clerk's celebrated engraving of Hutton's unconformity at Jedburgh, Scotland:
According to seismic data, these were interrupted by subtle angular unconformities, the Paleogene mid-Brookian unconformity in one and the Pliocene-Pleistocene in four.
Ossianic Unconformities: Bardic Poetry in the Industrial Age
Therefore an applicable layer thickness is adjustable by taking the amount of erosion by the presence of regional unconformities into account.
The three-dimensional geological modelling has helped SUCO identify unconformities in the stratigraphic section, construct a new set of maps at reservoir levels, which will be used as the basis for building a new static and dynamic model for the Ras Budran field, and identify several infill target locations for further drilling, the study stated.