| Summary: | From abstract: The Craig quadrangle, in southeastern Alaska, lies entirely within the Tongass National Forest and includes a large part of Prince of Wales Island, the largest island of the Alexander Archipelago. Sedimentary, volcanic, and metamorphic rocks of Paleozoic and Mesozoic age are exposed as complexly folded and faulted sequences. Paleozoic rocks occupy a broad geanticlinal area comprising Prince of Wales Island and the islands to the west. Metamorphosed Mesozoic rocks form a geosynclinal area along and east of Clarence Strait. Granitic and dioritic stocks and masses, mainly of Mesozoic age, intrude the Paleozoic and Mesozoic rocks. Remnants of volcanic rocks of Tertiary age exist on Suemez Island, and scattered areas of Tertiary clastic rocks and volcanic rocks are exposed near Clarence Strait. Deposits of Quaternary age are mainly thin glacial deposits and narrow bands of stream alluvium.
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