Question: What national park contains Geology that shapes the Pacific Northwest region of the United Stated and Canada?
Sentence (from "Geology of the Lassen volcanic area"): Heat from these subducting plates has fed scores of volcanoes in California, Oregon, Washington and British Columbia over at least the past 30 million years (see Geology of the Pacific Northwest) and is also responsible for activities in the Lassen volcanic area.
Relevant evidence: Yes