unconformities
Missing rock layers
Unconformities is the plural of unconformity, a geological term for a gap in the rock record where erosion or non-deposition interrupted continuous layering.
The surface represents missing time—sometimes millions of years.
The unconformities in this formation suggest the region was above sea level during the Jurassic.
Geologists read these breaks as chapters missing from Earth's history.
Break in activity
- gapUnfilled space between
- intervalDuration between two points
- missingNot present, whereabouts unknown
- chronologyTemporal ordering of events
duration · millions · eons · periods · ages · unrecorded · absence · lost
Sharp-edged or rawboned
- stratigraphyStudy of rock layers
- erosionalCaused by gradual wearing
- tectonicsStudy of crustal deformation
- outcropSurfacing native stone
sedimentation · buried · petrology · Grand Canyon · basement · contact · surface · transgression
Materials covering a mattress
- layersStacked levels or coatings
- stratificationDivision into distinct levels
- depositionFormal testimony under oath
- superpositionCoexisting in multiple states
facies · correlation · fossils · sedimentary · overlying · underlying · horizontal · tilted
Atmospheric breakdown of materials
- denudationRemoval of surface covering
- abrasionShallow surface wound
- scouringVigorous abrasive cleaning
- degradationDecline in condition
exfoliation · sediment · uplift · exposure · subaerial · submarine · truncation · beveling
hiatus
Break in activity
chronology · duration · millions · eons · periods · ages · unrecorded · absence · lost · eroded
angular
Sharp-edged or rawboned
- stratigraphyStudy of rock layers
- erosionalCaused by gradual wearing
- tectonicsStudy of crustal deformation
outcrop · sedimentation · buried · petrology · Grand Canyon · basement · contact · surface · transgression · regression
bedding
Materials covering a mattress
- layersStacked levels or coatings
- stratificationDivision into distinct levels
- depositionFormal testimony under oath
superposition · facies · correlation · fossils · sedimentary · overlying · underlying · horizontal · tilted · truncation
weathering
Atmospheric breakdown of materials
- denudationRemoval of surface covering
- abrasionShallow surface wound
- scouringVigorous abrasive cleaning
degradation · exfoliation · sediment · uplift · exposure · subaerial · submarine · truncation · beveling · leveling
conform, conformity, conformist, nonconformist, nonconformity, nonconforming, conformable, unconformity, nonconformer