1. A fine-grained volcanic rock of intermediate composition, typically dark gray or brown, formed from lava rich in silica and containing feldspar and other minerals.
Usage: geology; plural form of andesite; commonly found in volcanic regions and mountain ranges

Examples

• The volcanic peaks in the Andes Mountains are composed largely of andesites.
• Geologists collected samples of andesites from the recent lava flows.
• Andesites are commonly found in subduction zones where oceanic plates meet continental plates.
• The dark andesites in this region indicate a history of intense volcanic activity.
• Many of the rocks used in ancient construction were andesites quarried from nearby volcanic deposits.