Overlapping of late mesozoic orogens in western Idaho

Early formed rocks of the border zone of the Idaho batholith are thrust westward over the low-grade metavolcanic rocks of the Seven Devils Mountains. Late intrusions of the border zone cut out upper plate rocks and contact-metamorphose lower plate rocks. Granitic intrusions in the Seven Devils complex are metamorphosed near the border zone of the Idaho batholith. Such relationships are interpreted in the light of a regional synthesis to indicate the overlapping and oblique truncation of the eastern part of a belt deformed largely during Jurassic time by the western part of a tectonic belt active during early stages of the middle Cretaceous events that produced the Idaho batholith.