The Whitehorse Trough is a Mesozoic sedimentary basin in south-central Yukon that has been identified as an immature, gas-prone basin, based on a limited geoscience database. A total of 170 km of regional, multi-channel, multi-component Vibroseis seismic reflection data were acquired in 2004 across the northern Whitehorse Trough in order to improve understanding of its structural architecture. The shallow seismic images appear to depict broad antiformal and synformal structures, truncated by relatively steep faults. Strata interpreted as the Lewes River and Laberge groups seem to attain a maximum thickness of 6000-7000 m toward the west side of the Trough, with interpreted Laberge Group accounting for up to ~3000 m of this total. Maximum vertical relief of the structures is ~4000 m.