See the map of surficial deposits and the map of bedrock exposure for further information. The topography of Minnesota is governed in part by the different geological materials exposed at the surface. These different types of materials have different resistances to weathering and erosion, and also reflect different types of processes responsible for evolution of the geology. The geologic evolution of Minnesota can be understood in terms of Earth systems. A system is a group of interdependent materials that interact to form a unified whole and are influenced by related forces.
Systems generally involve cycles which operate as the system evolves.
The rock cycle is perhaps the most important of these cycles. You should study it now to understand the way in which geologic processes and earth materials interact to produce a dynamic Earth. Internal processes are driven by heat energy from remnant and radioactive sources. We sense these processes at the surface in the form of earthquakes, volcanic activity and mountain building. External processes are driven by heat energy from the sun and include weathering , mass wasting, erosion and deposition.