Examples of aphanitic igneous rock include basalt, andesite and rhyolite. The eruption were explosive tholeiitic andesite and dacite. Mount Shasta can release volcanic ash, pyroclastic flows or dacite and andesite lava. Most of the volcanic rock and tephra is of basalt or basaltic andesite. The eruptive products range from basaltic andesite to rhyolite and rhyodacite. Composite or stratovolcanoes often have andesitic magma and typically form the extrusive rock andesite. The lava flows consists of trachyandesite, andesite and dacite and pyroclastic deposits. Lascar rocks consist of andesite and dacite. Throughout its eruptive history, Mazama has produced basaltic andesite, andesite, and dacite lava. This produces a volcanic arc, composed of mainly basalt, andesite and rhyolite. Andesine occurs in intermediate igneous rocks such as diorite, syenite and andesite. Yamato Ridge is of continental origin and is composed of granite, rhyolite, andesite and basalt. The breccia includes pieces of andesite, dacite and massive sulfide. They consist of andesite, dacite, rhyodacite, rhyolite, trachy-basaltic andesite, trachyandesite and trachydacite. The ore occurs in altered shear zones in Tertiary dacite and andesite.