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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.


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


(ˌʌn kənˈfɔr mɪ ti)

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


A level where sedimentary rocks cover an older rock surface partly removed by erosion. The level marks a time gap.
References in periodicals archive ?
The erosive surface separating the Jurassic successions from the rocks underneath can be defined as an angular unconformity in central Sardinia and a non-conformity in the NE of the region.
One core is truncated by the mid-Brookian unconformity, a subtle angular unconformity. Upper Cretaceous strata beneath the unconformity dip one to two degrees to the north, while the Paleogene strata above are nearly horizontal.
The Simsima Formation was exposed and karstified prior to Muthaymimah being deposited with strong angular unconformity. Karst breccias fill fissures in the Simsima Formation.
The contact found in Timber Brook is an exceptionally well exposed angular unconformity, which outcrops along 800 m of the stream, but shows no evidence of paleoweathering in the basement gneiss (Fig.
One the most important evidence for this event is existence an angular unconformity between disrupted terrane andstratigraphic terrane.
The angular unconformity at Jedburgh, UK, first described by James Hutton, is then used to introduce concepts of time within the sedimentary record.
Abstract: The Warrensburg Sandstone, a Pennsylvanian alluvial valley-fill in Johnson County, Missouri, lies with angular unconformity on Desmoinesian Pennsylvanian marine strata comprised mainly of shales and thin limestones.
Horizontal sediments of the Montevarchi series are in angular unconformity with the former series.
Early Carboniferous deposits known as the El Raton Formation (Azcuy et al, 1981) and Jejenes Formation (Amos, 1954) overlie older Palaeozoic rocks along a strong angular unconformity.
The upper contact of the Horton Bluff Formation is almost everywhere an angular unconformity with the overlying Cheverie Formation; thus the angle of tilting of the Horton Bluff Formation and the extent of erosion also contributed to thickness variations.
Separated by a low angle angular unconformity, the Arroyo del Torreon Formation is covered by 700 m-thick Huaraco Formation.
Trenches excavated across the RFF reveal a distinct angular unconformity, steeply dipping strata cut by low-angle thrusts, and an unconformity below relatively undeformed strata [Hebeler et al., 2010].