formed as result of batholith A batholith is an area of mostly continuous plutonic (igneous intrusive) rock that covers an area larger than 100 square kilometers, formed in the planetary crust, and exposed by erosion. On Earth, Batholiths are almost always made mostly of felsic or intermediate rock-types, such as granite, quartz monzonite, or diorite. The form of erosion should be further specified. igneous intrusion process igneous intrusion planetary erosion