unconformity
Americannoun
-
lack of conformity; incongruity; inconsistency.
-
Geology.
-
a discontinuity in rock sequence indicating interruption of sedimentation, commonly accompanied by erosion of rocks below the break.
-
the interface between such strata.
-
noun
-
lack of conformity
-
the contact surface between younger and older rocks representing a discontinuity in the geological record. Most commonly it represents an erosional surface
Other Word Forms
Etymology
Origin of unconformity
First recorded in 1590–1600; un- 1 + conformity
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
It echoes James Playfair’s description of the “abyss of time” he glimpsed while viewing a strata unconformity at Siccar Point in 1788, when geology was first emerging as a science.
From The Guardian • Apr. 20, 2019
An unconformity: At Mount Stimson, the rover identified from sol 980 a thick sandstone unit overlying the lake deposits, separated by a geological feature called an unconformity.
From BBC • Mar. 22, 2018
She’s revising a manuscript describing an unconformity in the sedimentary layers of Mount Sharp, within the Gale crater, a record of the alternating wet-dry cycles on the planet.
From Science Magazine • Jun. 29, 2017
This unconformity was actually an ancient landscape surface on which sedimentary rock C was subsequently deposited perhaps by a marine transgression.
From Textbooks • Jan. 1, 2017
In Wales, the line between the Cambrian and Lower Silurian is somewhat ill-defined, and is certainly not marked by any strong unconformity.
From The Ancient Life History of the Earth A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science by Nicholson, Henry Alleyne
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
