SAVONOSKI CRATER,ALASKA: A POSSIBLE METEORITE IMPACT STRUCTURE

Savonoski Crater, a small basin about 1700 feet in diameter, is located on a ridge of gently-dipping Jurassic sandstone in Katmai National Monument, southwestern Alaska. Reconnaisance geological, geophysical, and petrographic studies suggest that it was formed either by volcanic processes or meteorite impact prior to the end of the latest glaciation in the region. Surface ejecta, if originally present, apparently have been removed by glaciation. No distinctive shock-metamorphic effects were observed in the few rock specimens collected. Final determination of the crater's origin will require more extensive field studies or drilling in the center of the crater.