Igneous Intrusive Landforms

Abstract

If you come across igneous rocks consisting of coarse-grained minerals in a landscape, chances are you are standing on an igneous intrusion that crystallized several kilometers below the Earth’s surface. Igneous intrusions are fascinating windows into magmatic processes that take place deep in the Earth’s crust and cannot be observed directly with our current scientific methods at hand. But igneous intrusions that have been uplifted and exposed by erosion such as plutons and dikes provide insights about magmatic processes that took place millions of years ago and we can deduce the size, shape and magma composition by studying their geology exposed at the Earth’s surface. Plutons are fundamental building blocks of the continental crust and are often composed of the oldest rocks in Earth’s history, while dikes represent the fossil remains of the “volcanic plumbing system”.