Abstract

The Whitehorse trough is an Early to Middle Jurassic underexplored and undrilled sedimentary basin in the northern Canadian Cordillera that is prospective for oil and gas. It records deposition in a collapsing forearc that evolved to become a synorogenic piggyback basin within the nascent Cordilleran orogen. The basin developed atop the Triassic and older arc terranes of Stikinia and Quesnellia, and locally overlaps the Cache Creek accretionary complex. A regional seismic survey and bedrock mapping across the northern Whitehorse trough in Yukon indicate that Jurassic strata of the Laberge Group are up to 3000 m thick and were deformed by southwest-verging folds and thrust faults. These structures have an overall en echelon, sigmoidal pattern that is consistent with dextral transpression associated with strike-slip displacement along the Teslin and Braeburn faults. The structures likely began developing in Middle to Late Jurassic and were further enhanced during the mid-Cretaceous. Fold-and-thrust structures of the northern Whitehorse trough present suitable structural plays in areas where Jurassic strata with good source rock potential and adequate thermal maturity are most prospective.