Boss (geology)
In geology, a stock is a discordant igneous intrusion having a surface exposure of less than 40 sq mi (100 km2), differing from batholiths only in being smaller. The term stock usually refers to individual, relatively small plutons (<20 km diameter), usually in relative isolation. Most stocks are probably the cupolas of hidden batholiths. Circular or elliptical stocks may have been vents feeding former volcanoes.
A boss is a small stock.
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