Blackrocks basalt outcrop - 1.7 billion years old (Presque Isle Park)

Step Back in Time at Marquette, Michigan’s Beautiful Blackrocks

Along the southern shore of Lake Superior in Michigan’s Upper Peninsula lies an amazing outcrop of ancient volcanic basalt composed of the remnant cooled lava flows of ancient volcanic activity. This amazing outcrop, estimated to be 1.7 billion years old, is located on Presque Isle, a 323-acre peninsula extending into Lake Superior on the north…