Structural fabric of the North American continent, as defined by gravity trends

Abstract

The structural significance of the trends is demonstrated by the close correspondence between gravity domains defined on the basis of trend patterns, and structural domains based primarily on geological criteria. This relationship has been used to extend the Superior and Grenville provinces and the Trans-Hudson orogen southward from the Canadian Shield. Gravity trend patterns also reveal prominent lineaments that likely signify major faults in the craton and/or Phanerozoic rocks. It is shown that the continent has grown outward from the Archean Superior and Wyoming provinces by accretionary plate tectonic processes involving, in many cases, continental collision. Boundaries of buried Proterozoic age provinces in the southern part of the continent have no strong gravity expression. A correlation between Phanerozoic intra-cratonic sedimentary basins and discrete gravity domains points to a strong influence of crustal processes in their development. -from Authors