The geosynclines are the major structural and the sedimentational units of the crust of the earth. They are elongated trough like depressions submerged beneath the sea water. They are considered to be the future of sites of the mountain building activity and of the Fold Mountains. These basins become filled with very great thickness of the sediments and along with the accumulation of the pile of the sediments there occurs progressive subsidence of the floor of the ocean basin
In 1873, Dana coined the descriptive term of geosyncline for a linear belt of shallow water sediments that accumulate to a great thickness and then deform into fold mountains, but full concept on which it was based goes back to Babbage (1833) and Harschal (1836), who assumed the great depressions of the earth were prerequisite for the emergence of thick bodies of strata. The concept is further rooted in the ideas of James Hall who in1857 recognized folds to be natural features that accompany and are consequences of subsidence and sedimentation. Hall spoke of great synclinal axes along which smaller scale anticlines and synclines are formed what Hall labelled large syncline in this sense. Dana subsequently called geosyncline and assigned the term synclorium that is mountain ranges of the syncline to the system of the mountain chains that developed from them.
In 1873, Dana coined the descriptive term of geosyncline for a linear belt of shallow water sediments that accumulate to a great thickness and then deform into fold mountains, but full concept on which it was based goes back to Babbage (1833) and Harschal (1836), who assumed the great depressions of the earth were prerequisite for the emergence of thick bodies of strata. The concept is further rooted in the ideas of James Hall who in1857 recognized folds to be natural features that accompany and are consequences of subsidence and sedimentation. Hall spoke of great synclinal axes along which smaller scale anticlines and synclines are formed what Hall labelled large syncline in this sense. Dana subsequently called geosyncline and assigned the term synclorium that is mountain ranges of the syncline to the system of the mountain chains that developed from them.