The structure of the Tintina Fault Zone (TFZ) within the Tintina Trench in west-central Yukon is almost completely unknown, due largely to very poor exposure, and thick overburden cover. In this study, we have used digitally enhanced Landsat Thematic Mapper thermal imagery as a basis for a preliminary structural interpretation of the Tintina Trench in the Dawson-McQuesten area. Linear features visible on the enhanced images are divided into first order (obvious, long strike-length), second order (less obvious, shorter strike-length), and third order (subtle, very short strike-length) lineaments. The images show major, NW-SE trending first and second order lineaments within the Trench which we interpret to be separate strands of the TFZ. Sag ponds and fresh fault scarps in glacial drift along these lineaments attest to relatively recent fault activity. NE-SW trending first and second order lineaments that cut obliquely across the Trench are considered to be late faults and fracture zones which formed after major strike-slip displacement on the TFZ. Third order lineaments show strong preferred orientations over large portions of the image area, and are thought to reflect overall structural grain (bedding or foliation trends and/or regionally-developed joint patterns).
