Dyke and sill are environmental terms used to designate an invasion, typically a mass of igneous or volcanic rocks that have effectively entered, penetrated, and implanted into layers of additional rock or landform. Dykes and sills are often connected with volcanoes, though they are not limited to those landforms.
Dykes are vertical. Their creation is reliant on the consistency of pressure that comes. The usual grouping of dykes can be diabase, basaltic, to granitic, or rhyolitic. Dykes are made to be in between and parallel to their surroundings bedding plates. On the other hand, sills are created the same way.
Sills are generally comprised of medium-grained rock and often encompass certain rare types of deposits in their formation. A sill as a form of rock is concordant because it is parallel to the original rock or landform. Sills are harder to identify since they exist parallel to planes and rocks.