194 



C. SCHUCHERT THE NORTH AMERICAN GEOSYNCLIXES 



donian deformation of late Silurian time, but, since at least the Penn- 

 sylvanian strata are involved in the folding, it is clear that the origin of 

 these ranges can not be older than late Pennsylvanian time. On the 

 other hand, the Triassic strata appear to be unfolded and may represent 

 a transgression restricted to the southwestern and more open remainder 

 •of the Franklinian geosyncline. 



Xature of ]\Ieditekraxeaxs compared avith Geostxclixes 



gexeral discussiox 



The American theory of geosynclines is widely accepted by the Euro- 

 peans, but their typical area for this structure is the mountains of south- 



EiGL'RE 18. — TTorhJ Chart sltoicing Geosi/iiclines and hypothetic Continents during 



Mesozoic Time 



After Haug, 1909. from Ruedemann. 1922. 



'crn Europe and the Roman Mediterranean, extending into Asia, the site 

 ■of a former greater mediterranean (see fig-ure 18 ) . To this very extensive 

 seaway of the geologic past, Suess many years ago gave the name Tethys. 

 •Since Tethys was the consort of Oceanus, we see in this linkage of the 

 gods also the idea that mediterraneans have the characteristics of oceans. 

 This is true of mediterraneans in nearly all of their physical aspects 

 •except as to size and shape, since their typical form is that of elongate 



