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Pacific NW Geologic Mapping Project

Geologic maps of the North Cascades

TKmd-1. View northeast from head of Sonny Boy Creek [SRne]. The Entiat Fault separates Marblemount pluton (meta-quartz diorite, TKmd) from Napeequa Schist (Kns). The pluton is overlain by Cascade River Schist (TKcs). The supracrustal rocks were intruded by the Eldorado Orthogneiss (TKgo). Rocks southwest of the fault were metamorphosed in the Cretaceous; metamorphism of rocks to the northeast continued into the Eocene (hence, TKns ). The Miocene Cascade Pass dike (QTcp) intrudes the older rocks. The shallowly intruded dike produced an explosion breccia that crops out on The Triplets. Contacts (thin lines) and faults (heavy lines) dashed where approximately located and dotted where hidden in this view. View image without annotation
Other photos that show unit TKmd:

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Photo Indices: Captions (Additional photos home) | Map | Young rocks and deposits | Older rocks west | Older rocks east