What does syncline mean?
A syncline is a geological fold in which rock layers bend downward toward the center, creating a trough-shaped structure. It commonly forms when compressional forces buckle layers of sedimentary rock. The term is distinguished from an anticline, an upward-arching fold with the opposite geometry. Synclines can be broad and subtle or sharply folded, and they may be associated with valleys, sedimentary basins, and the preservation of younger rocks in their centers. In ordinary writing, the word is specialized and most often encountered in geology, structural geology, and mapping. Its defining feature is the downward dip of the strata toward the middle of the fold.
nounA syncline is a fold in rock layers that bends downward toward its center, forming a trough-like geological structure. It is the opposite of an anticline, where the layers arch upward.
- A downward fold in rock layers, especially one produced by compressional forces.
- A trough-like structural depression formed by the downward bending of strata.
"The geologists identified a broad syncline containing layers of limestone and shale."
"Sedimentary beds dip gently into the syncline."
"The syncline contains fossils that help date the surrounding rock layers."
The plural is synclines.
"The survey mapped several synclines across the region."
A syncline is a geological fold that makes the layers of the Earth curl downward like a spoon.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does syncline come from?
The word comes through Latin from Greek roots meaning “together” and “to slope” or “to lean,” reflecting the downward inclination of layers toward the center of a fold. It developed in English in the 19th century as a specialized geological term alongside the contrasting term anticline.
Related word forms
How syncline is actually used
This is a specialist geology term. It is normally used for a fold in rock layers, although it may also describe the broader trough-like structure associated with such a fold.
Easily confused with syncline
A syncline dips downward toward its center, whereas an anticline arches upward.