Which type of intrusive rock formation is often associated with large areas greater than 100 km²?

Batholiths are large masses of intrusive igneous rock that have been formed from the cooling of magma beneath the Earth's surface. They are characterized by their extensive size, typically exceeding 100 square kilometers in area. This significant size distinguishes them from other types of intrusive rock formations. Batholiths are often composed primarily of granitic or dioritic rock and can rise to great heights, forming mountainous regions when exposed through erosion over geological time.

The formation of batholiths usually occurs over long periods as magma pushes its way into the surrounding rock layers and slowly crystallizes. Because of their massive scale, batholiths can have a substantial impact on the surrounding geology, including influencing local metamorphism and the formation of other geological structures.

Understanding the characteristics of batholiths helps in the study of geological processes and the history of Earth's crust, as they represent major events in the planet's volcanic activity.