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Pacific NW Geologic Mapping Project

Geologic maps of the North Cascades

Tcaf-1. View towards west from Keyes Peak of 300-m-high east face of Columbia Peak [SKne]. Miocene breccia of Keyes Peak (volcanic rocks of the Fifes Peak episode, Tcaf) overlies Eocene extensional rocks (Tev) and both are intruded by a small stock of the Grotto batholith (Snoqualmie family of the Cascade Magmatic Arc, Tcas). Contacts dashed where approximately located. Photographed in 1980. View image with annotation
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Photo Indices: Captions (Additional photos home) | Map | Young rocks and deposits | Older rocks west | Older rocks east