Igneous intrusions are formations that occur when molten rock, or magma, rises from deep within the Earth and solidifies underground. This process creates various types of rock, including granite and diorite, depending on the mineral composition and cooling rate. These intrusions can vary in size, from small dikes to large batholiths. As the surrounding rock erodes over time, these intrusions can become exposed at the surface. They play a significant role in the geological landscape, influencing soil composition and providing valuable resources. Understanding igneous intrusions helps geologists learn about Earth's history and the processes that shape its crust.