The Geological Framework of the Yukon Territory

• Main Author: C. Hart
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Yukon; Alaska
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.602.169; http://www.geology.gov.yk.ca/pdf/bedrock_geology.pdf

The Yukon Territory occupies the northern portion of a large geologic (and physiographic) province known as the Cordillera. This province is composed of relatively young mountain belts that range from Alaska to Mexico. Like most of the Cordillera, Yukon is composed of a diverse array of rock types that record more than a billion years of geological history. Most of the rocks have been affected by folding, faulting, metamorphism and uplift during various deformation events over at least the last 190 million years. This deformation has resulted in a complex arrangement of rock units and the mountainous terrain we see today. In Yukon, there are two main geological components which are largely separated by a major, northwest-trending fault (the Tintina): 1) the northeastern region is composed of a thick, older sequence of sedimentary rocks which was deposited upon a stable geological basement; and 2) the southwestern region is composed of a younger, complex mosaic of varying rock types that amalgamated and accreted to the stable sedimentary package. This paper briefly describes the geological framework of Yukon south of 65 degrees N and, with some exceptions, uses the Tectonic Assemblage Map of the Canadian Cordillera (Wheeler and McFeely 1991) and the Terrane Map of the Canadian Cordillera (Wheeler et al. 1991) as a foundation. However, some of the names used on these maps have been superseded by new terminology and they are included in this paper. Recent brief syntheses of Yukon physiography and geology are rare (Tempelman-Kluit, 1979; 1981), although geological compilations of Cordilleran geology are numerous and contain useful information about Yukon geology (Monger