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Visual Glossary

This conglomerate is from North Cascades National Park. The clasts (larger pieces of rock) are cobbles of granitic rocks (white with black speckles).


spacer image A sedimentary rock made of rounded rock fragments, such as pebbles, cobbles, and boulders, in a finer-grained matrix. To call the rock a conglomerate, some of the consituent pebbles must be at least 2 mm (about 1/13th of an inch) across

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This page was last updated on 11/17/99