Knowledge of the deformation front of the Richardson Anticlinorium is an important component of assessments for regional hydrocarbon potential; but sparse outcrop in the Peel Plateau, Yukon has made geological interpretations difficult and the results of reconnaissance mapping uncertain. To date, a single fault has been inferred to define the eastern limit of deformation. In this paper, we present stratigraphic and structural interpretations of multi-channel seismic reflection data collected in an early phase of hydrocarbon exploration. Early Tertiary deformation is expressed as a series of thrust faults, folds and back thrusts, not a single through-going fault. Deformation has been concentrated on several lithologic transitions: a pinch out of syn-rift sandstones and the transition from carbonate platform to basinal shales. The Middle Ordovician to Middle Devonian eastern margin of the Richardson Trough is imaged as clinoforms and a carbonate buildup; clinoforms can be mapped about 75 km along strike. Integration with aeromagnetic data allows us to construct a map of subsurface structures along the eastern deformation front associated with the Richardson Anticlinorium. Faulted anticlines and facies pinch outs are potential traps although any play in this region remains hypothetical.