Minnesota River Valley - Igneous and Metamorphic Petrology - Spring semester

Outcrops in the Minnesota River Valley comprise some of the oldest rocks in North America, ranging from the 2.6 billion year old Ortonville and Sacred Heart granites to the 3.6 billion year old Morton and Montevideo gneisses. These rocks record some of the earliest stages in the formation and growth of our continent and provide a great opportunity to study the field characteristics of and relationships between rocks that are highly metamorphosed and deformed.