The Grand Marais Public Library is excited to host geologist Al Trippel to present on the geology of the North Shore on Friday, August 15, from 5-7 PM. 

In this presentation, Al Trippel will explain the geological and historical context to the rocks we find, whether washing up on the shores of Lake Superior or unearthing themselves on the Superior Hiking Trail. Cook County is home to a variety of rock types, some common and some extremely rare on earth. The presentation will show us where we sit in the regional “big picture” of the Canadian Shield “stable” craton.

The presentation will include a slide show, exemplary rocks, as well as digital and print resources about how and where to find agates and other fascinating rocks and minerals. A question and answer session and rock-identification segment will conclude the presentation. If bringing in rocks for identification, limit rock-ID questions to two rocks per person,for time will be limited. 

This free program is for rock hounds of all ages.

Al Trippel lives in Grand Marais and grew up around rocks in the Midwest and Western US.  From a childhood hobby, to a high school job, to a career in mining—and now a passion during retirement (actually he calls it “refirement”)—rocks continue to awe and inspire him. Much of his lapidary and jewelry making utilizes rocks and minerals found along the way.

The library is continuing its 2025 Writer in Residence series with a special work-in-progress reading from award-winning author Brian Malloy on Wednesday, August 20, from 7-8 PM. Follow us on Facebook stay up to date on our free and enriching programs: www.facebook.com/grandmaraislibrary.