Teaching Mineralogy, Petrology and Geochemistry Post-Workshop Field Trip

An Excursion to the Classic Bedrock Localities of Northern Minnesota With a Focus on Teaching and Learning in the Field

Tholeiitic basalt lava flows of Mesoproterozoic North Shore Volcanic Group, North Shore, Lake Superior. Photo Credit: John Goodge.

Field Trip Leaders: Karl Wirth, John Goodge, Dexter Perkins

The goal of this three-day field trip is to explore the opportunities and challenges of teaching geology in the field. The trip will use several classic bedrock localities within the scenic Lake Superior region of the Mesoproterozoic Midcontinent Rift to foster discussions about pedagogies that can be used for teaching students in the field. Extended visits to a world-class turbidite sequence, layered igneous intrusions, and well-preserved volcanic and sedimentary sequences will provide participants opportunities to experience learning geology as student, and to explore new ways to improve student learning in the field.

Dates: August 11-13 (Leaving U MN area Thurs AM, returning Saturday night)

Cost: The cost of the field trip is $325. This includes transportation, Thursday and Friday night lodging (double occupancy), lunches and snacks on the road, and guidebook. Breakfast and dinner will be on your own at local restaurants. Note: we will be returning to the MSP area on Saturday night, and you will also need to plan for lodging for this night. We will attempt to make group arrangements expecting Sunday departures. The cost of Saturday night lodging is not included in the field trip fee.

Registration: Space is limited to 30 participants, and was accepted on a first-come first served basis. Registration ended May 15.

Tentative Itinerary

Palisade - Midcontinent Rift rhyolite flow at Palisade Head (foreground) and Shovel Point (background). North Shore, Lake Superior. Photo Credit: Karl Wirth

Day 1

  • Thomson Dam - Animikie Basin turbidites, dikes, and folds
  • The Midway unconformity (Penokean Thomson greywackes unconformably overlain by basal sediments and basalt of Mid-continent Rift)
  • Bardon Peak - layered ultramafic and mafic rocks of the Duluth Complex; spectacular overview of estuary
  • Pahoehoe and rhyolite flows along the lake shore just north of Duluth
  • Palisade rhyolite at the Hwy 1 intersection, in order to discuss formation of folds in Si-rich volcanic flows.
  • Split Rock Lighthouse - anorthosite xenoliths in diabase
  • Beaver Bay sequence - rhyolite, basalt, granite dikes, anothosite xenoliths, zeolites
  • The rhyolite and Granite Xeno near the Silver Bay Gun Club

Pipe vesicles at base of pahoehoe flow, Sugarloaf Cove Natural Scenic area, near Little Marais, MN. Photo Credit: John Goodge


Day 2

  • Anorthosite xenoliths (north of Hwy 1, or Carleton Peak)
  • Sugar Loaf Cove - pahoehoe flows, clastic dikes, sheared pipe vesicles, zeolite-facies metamorphism
  • Sonju Lake Intrusion - magmatic differentiation in a mafic layered intrusion
  • Kennedy Creek basalt flows - tholeiite basalt flow features in a layered sequence


Soudan - Archean Soudan banded iron formation. Soudan Underground Mine State Park.Photo Credit: Karl Wirth

Day 3

  • Gunflint Trail - BIF, stromatolites, tonalite, and Sudbury impact breccia
  • Giant's Range Batholith - mineralogy, classification, alteration, timing
  • Ely greenstone and pillow basalts - facing directions, mineralogy, tectonic setting
  • Pike River Turbidites - graded bedding, soft-sediment vs. tectonic deformation
  • Soudan Archean BIF
  • Penokean Paleoproterozoic BIFs on the Iron Range

Other Images of the Field Trip Route


Greywacke-slate units of Paleoproterozoic Thomson Formation exposed along St. Louis River near Carlton, MN. Photo Credit: John Goodge.
Soft-sediment fold in Archean greywacke, bounded by plane-bedded graded turbidites, near Tower, MN. Photo Credit: John Goodge.


Palisades Rhyolite at Shovel Point, North Shore, Lake Superior. Photo Credit: John Goodge.
Joints and microfaults in Archean greywacke-shale units. Near Tower, MN. Photo Credit: John Goodge.


Glacial striations on polished basalt flows, North Shore Volcanic Group, Duluth, MN. Photo Credit: John Goodge.
Pike River - Archean greywacke at Pike River Dam. Near Tower, MN.Photo Credit: Karl Wirth.


Keweenawan Pahoehoe - Ropy pahoehoe flow surfaces, Mesoproterozoic olivine tholeiite flows. Near Duluth, MN. Photo Credit: Karl Wirth.
Duluth Gabbro - layered troctolite near base of Mesoproterozoic Duluth Complex. Duluth, MN. Photo Credit: Karl Wirth.