Cross-bedding
Inclined internal sedimentary laminae or strata truncating against broader bounding surfaces, commonly produced by migrating dunes or ripples.
Language and route: English descriptive compound cross + bedding; cross-set synonym often used. English descriptive compound cross + bedding; cross-set synonym often used
Literal gloss: bedding inclined across larger beds
The name and its history
First geological naming act not verified · First geological printed use not verified
- What does the word literally mean?
- Immediate borrowing/formation pathway: English descriptive compound cross + bedding; cross-set synonym often used. Linguistic gloss: ‘bedding inclined across larger beds’. This is not automatically the original namer’s stated reason.
- What did the original author mean?
- Early stratigraphers observed inclined laminae within larger beds before sedimentologists connected such arrangements consistently to current-generated ripples and dunes. No specific original coiner is established.
- Why was the name needed?
- Observers needed to distinguish true tilted rock strata from internal depositional geometry and to infer conditions of sand transport.
- What evidence supported the original concept?
- Truncated inclined foresets, grain-size contrasts and modern stream/shore/wind analogues; palaeocurrent interpretation needs orientation of sets and knowledge of bedform migration.
- How has geology changed the concept?
- Cross-bedding can develop under river, tidal, wind and shallow-marine flows; an inclined foreset is not by itself evidence for a single palaeoenvironment.
Further historical context
Early stratigraphers observed inclined laminae within larger beds before sedimentologists connected such arrangements consistently to current-generated ripples and dunes. No specific original coiner is established.
Observers needed to distinguish true tilted rock strata from internal depositional geometry and to infer conditions of sand transport.
Truncated inclined foresets, grain-size contrasts and modern stream/shore/wind analogues; palaeocurrent interpretation needs orientation of sets and knowledge of bedform migration.
Cross-bedding can develop under river, tidal, wind and shallow-marine flows; an inclined foreset is not by itself evidence for a single palaeoenvironment.
Editorial qualification
First coinage/priority not independently established; historical narrative is a source-bounded reconstruction.
Related names
Sources
- British Geological Survey, Rock Classification Scheme, Volume 3 overview — Modern descriptive sedimentary classification; does not establish historical first use
- Wentworth (1922), A Scale of Grade and Class Terms for Clastic Sediments — Original 1922 classification paper, verified title/DOI and journal pagination; full article not transcribed
- USGS, Lithologic classification of geologic map units — Alternative modern operational vocabulary, including mudrocks