Descr: This experiment is designed to image the crust and upper mantle beneath the transition from the tectonically active Canadian Cordillera into the Archean Slave province, with and additional goal of supplying unprecedented resolution of the lower-mantle and core-mantle boundary structure beneath the Pacific rim and Hawaii. It consists of 48 broadband seismometers deployed for a 16-18 month period in Northwest Canada, stretching from Edmonton, Alberta to Whitehorse, BC, with an additional arm extending to Yellowknife, NWT.