Geosyncline
From Freepedia
Geosyncline refers to a thick pile of sedimentary rocks that were deposited in a deep marine basin and subsequently compressed, deformed, and uplifted into a mountain range with attendant volcanism and plutonism. The geosynclinal theory was developed in the late 19th and early 20th centuries and was the widely accepted explanation for the origin of most mountain ranges until the explosion of plate tectonics in the 1960s.
Geosyncline, in geology, a major structural feature of the Earth's crust. A geosyncline begins as a belt of especially active sedimentation and eventually becomes trough-like. This trough may remain intact for millions of years, but as a rule, the sediments deposited in it become severely folded and uplifted to form a mountain chain.
