Subsidence analysis of the Cordilleran miogeocline: Implications for timing of late Proterozoic rifting and amount of extension Available to Purchase

Tectonic subsidence of the Cordilleran miogeocline in the western United States during late Proterozoic through early Paleozoic time is best explained by rifting and subsequent thermal contraction of the lithosphere. The tectonic component of subsidence can be calculated by removing the isostatic effects of sediment and water loading. The resultant subsidence curves indicate that rifting began about 600 m.y. ago and that extension of the lithosphere during rifting was in excess of a factor of 1.3.