<P> Geosyncline originally called a geosynclinal is an obsolete geological concept to explain orogens which was developed in the late 19th and early 20th centuries before the theory of plate tectonics was envisaged . A geosyncline was described as a giant downward fold in Earth's crust with associated upward folds (geanticlines, geanticlinals) that preceded the climax phase of orogenic deformation . The theory served as a means to explain the formation of mountains . </P> <P> The geosyncline concept was first developed by the American geologists James Hall and James Dwight Dana in the mid-19th century during the classic studies of the Appalachian Mountains . Émile Haug actualized the geosyncline concept and "reintroduced" it to Europe with a 1900 publication . Eduard Suess, a leading geologist of his time, disapproved the concept of geosyncline and argued in 1909 against its use due to its associated theories . This did not stop further development of the concept by Leopold Kober and Hans Stille in the first half of the 20th century, both of whom worked on a contracting Earth framework . Stille and Kober had rather similar views . </P> <P> The development of the geosycline concept in the aftermath of Eduard Suess' book Das Antlitz der Erde (1883--1909) by Stille and Kober was not unchallenged as another school of thought was led by Alfred Wegener and Émile Argand . This competing view rejected Earth contraction and argued for continental drift . These two views can be called fixist in the case of geosyncline theory and mobilist for the support of continental drift . </P> <P> Marshall Kay adapted the geosyncline concept to plate tectonics in 1951 as did John F. Dewey and John M. Bird in 1970 . The term continued to have usage within a plate tectonics framework in the 1980s, albeit Celâl Şengör argued in 1982 against its use considering its association to pre-plate tectonics ideas . </P>

The great geosyncline from which the himalyas is assumed to have originated is known as