Half Dome in Yosemite National Park – an exposed portion of the Sierra Nevada Batholith.

A batholith is a large irregularly shaped body of intrusive igneous rock, usually covering more than 100 square kilometers (40 sqare miles) and extending to a great depth (up to 30 kilometers). A batholith is usually associated with a mountain belt and is often surrounded by metamorphic rock.


A stock is a smaller body that is typically fed from a deeper level batholith. Stocks may have been feeders for volcanic eruptions, but because large amounts of erosion are required to expose a stock or batholith, the associated volcanic rocks are rarely exposed.