A Theory of Crustal Development Based on Experimental Analysis of Vertical Uplift: ABSTRACT

Abstract

By constructing simple model experiments it can be shown that vertical uplift can produce first-order tectonic features similar to those seen in nature. Models of known tectonic features such as the orogen and tensional furrow can be simulated by inflating and deflating a large elongate balloon below layers of clay and lime slurry. Symmetrical and asymmetrical orogens can be simulated as well as simultaneous and migrational orogens. The simultaneous orogen forms as the result of the balloon inflating as a unit along its length. The migrational orogen is formed by the balloon expanding progressively along its length. The migrational expansion causes compressional folds to develop ahead of the expanding front. Drag folds and wrench faults are formed along the flanks. The first-order tectonic features of known areas can be modeled by using simulated orogens placed in the same relative positions as the naturally occurring features. Some of the areas modeled are the Rocky Mountains, the California system, and the central Western Hemisphere. Transverse and extension faults can be produced experimentally by vertical uplift. Offsetting uplifts of model orogens produce transverse faults as does differential uplift along the same model orogenic belt. The model transverse and extension faults compare favorably with those observed in nature. End_of_Article - Last_Page 1825------------