THE INFLUENCE OF AMERICAN GEOLOGISTS WORKING WEST OF 100TH MERIDIAN DURING THE LATTER HALF OF THE 19TH CENTURY ON EDUARD SUESS

Eduard Suess (1831-1914) was one of the gratest geologists who ever lived, if not the greatest. His four-volume Das Antlitz der Erde (The Face of the Earth: 1883-1909) is the most complete tectonic synthesis ever attempted by an individual and is one of the most complete ever. For this work, Suess compiled and synthesised world-wide data to conclude that horizontal motions on earth and fault-controlled subsidence were the two dominant processes that governed terrestrial tectonics. Especially for vertical motions, Suess used a great deal of data gathered from the west of 100th meridian in the United States. But he also used the work of American geologists to understand tectonics/magmatism relationships. He was constantly up-to-date with American developments and even the large expedition reports of limited editions regularly reached his desk in Vienna. It is in this regard surprising that Suess did not think any primary vertical uplifts existed in the world. He interpreted even the Colorado Plateau as a remnant left over after its surroundings had subsided along steep faults. The laccoliths he thought were intruded into lense-shaped 'maculae' formed by differential folding of enveloping layers. Suess's synthesis of the structure of the North American Cordillera and his remarkable interpretation of even local structures (such as the origin of the Death Valley as a strike-slip related rift) shows, in addition to his genius, how well the geology of the western United States had been described by its geologists. In sharp contrast to the 'east coast' schools of geology, the 'westerners' had better material to work with and were better prepared intellectually to deal with the great complications offered by geology. The easterners had largely remained in a natural history mode. The westerners by contrast were keen to explain. Their explanatory observations were hypotheses presented with a view to be discussed and discarded for better ones. This suited Suess' mode of research.