North-Central Section

Field Trips

There will be no field trips in person this year, but many of the field trip organizers have uploaded their field trip stops to Flyover Country, a mobile app created by Shane Loeffler and others at the University of Minnesota.

This app allows you to explore the geology and natural history below your flight, along a hike, or on a field trip. The app is funded by the National Science Foundation (NSF) and available for free on both Android and iOS. GSA has also collaborated with Flyover to make former guidebooks available on this platform. You can learn more and download the app at FlyoverCountry.io.

For additional information, please contact the field trip chair: Carrie Jennings, cjennings@freshwater.org.

Pre-Meeting Trips

FT1. Northern Minnesota Peatland and Soil Research Tour.

Sat., 16 May, 9 a.m.–Sun., 17 May, 5 p.m. Cost: $300. Max.: 20 participants.

Ed Nater, nater001@umn.edu; Kyungsoo Yoo, Univ. of Minnesota; Stephen Sebestyen, U.S. Northern Forest Research Station.

Description: Tour the U.S. Forest Service Marcell Experimental Forest (www.nrs.fs.fed.us/ef/marcell/) and the DOE-funded SPRUCE (mnspruce.ornl.gov) long-term research sites and learn about ongoing research on ecosystem response, peatland hydrology, and mercury and sulfur biogeochemistry. The second day will focus on research sites that explore soil and ecosystem impacts of invasive earthworm species in forests near Itasca State Park.

FT2. Geology Field Trip along the Mesabi Iron Range with Fossil Collecting.

Sun., 17 May, 7:45 a.m.–7 p.m. Cost: $95. Max.: 33 participants.

Allyse Freeman, allyse.freeman@mndiscoverycenter.com, Minnesota Discovery Center, John Westgaard, Science Museum of Minnesota.

Description: Participants will tour the Mesabi Iron Range to see both geologic and historic sites including a mine overlook, a historical mine tour at the Hill Annex State Park, the Minnesota Discovery Center, and the Museum of the Iron Range in Chisholm. There will be ample time to collect Late Cretaceous marine fossils from mine spoil at Hill-Annex State Park.

FT3. St. Louis River Sediment Remediation, Aquatic Habitat Restoration, and Harbor Tour.

CANCELED

Ben Sheets, BSheets@barr.com, Barr Engineering.

Description: Cruise of Lake Superior from downtown Duluth to the mouth of the St. Louis River to discuss sediment remediation sites, aquatic habitat restoration, and harbor features.

FT4. The Sandstone Karst of Pine County, Minnesota.

Sun., 17 May, 7:30 a.m.–6 p.m. Cost: $115. Max.:28.

Calvin Alexander, University of Minnesota, alexa001@umn.edu; Greg Brick.

Description: Visit the sinkholes, sinking streams, large springs, and caves that have developed in the very pure quartz sandstone of the Hinckley Sandstone of Pine County, Minnesota, USA. These classic karst geomorphic features are developed near Askov, Minnesota, and Banning State Park.

Trips During the Meeting

FT5. Walking Tour of Minnesota Point.

Mon., 18 May, 4–6 p.m. Cost: Free.

Harry Jol, jolhm@uwec.edu, Univ. of Wisconsin–Eau Claire; Andy Breckenridge, Univ. of Wisconsin–Superior.

Description: The barrier bar complex formed by Wisconsin and Minnesota Points is the geomorphic feature that defines the “Twin Ports” of Superior and Duluth. The objective of this walking tour is to introduce participants to world’s largest freshwater baymouth bar and discuss various topics including coastal progradation and erosion, aeolian foredunes, effects of recent lake level changes, and continuing research including piping plover restoration, subsurface imaging, and coring. The target audience for the field trip is K–12 teachers and students, but all are invited.

FT6. Geology under the Surface: Lake Superior and the Research Vessel Blue Heron—Morning Trip.

Tues., 19 May, 8 a.m. Cost: $15. Max.: 15 participants.

Doug Ricketts, ricketts@d.umn.edu; Nigel Wattrus, Univ. of Minnesota Duluth.

Description: Join us on a cruise aboard the Univ. of Minnesota’s research vessel, the Blue Heron. During the cruise, scientists will demonstrate the scientific capabilities of the vessel including a suite of coring and geophysical instruments. Participants will observe features resulting from post-glacial isostatic rebound.

FT7. Geology under the Surface: Lake Superior and the Research Vessel Blue Heron—Afternoon Trip.

Tues., 19 May, 1 p.m. Cost: $15. Max.: 15 participants.

Doug Ricketts, ricketts@d.umn.edu; Nigel Wattrus, Univ. of Minnesota Duluth.

Description: A second chance to join us on a cruise aboard the Univ. of Minnesota’s research vessel, the Blue Heron. During the cruise, scientists will demonstrate the scientific capabilities of the vessel including a suite of coring and geophysical instruments. Participants will observe features resulting from post-glacial isostatic rebound.

Post-Meeting Trips

FT8. Minnesota’s Minerals, Mining, and the Environment of the Mesabi Iron Range.

Weds., 20 May, 7 a.m. –6 p.m. Cost: $85. Max.: 22 participants.

Megan Kelly, megan.j.kelly@state.mn.us; Heather Arends, MnDNR Lands and Minerals.

Description: Spend the day in the oldest continuously operating mining district in North America. The tour stops at Minnesota mine features and operations and state-run facilities including one of the largest publicly available drill core libraries in the U.S. and a research site focused on environmental aspects of mining in Minnesota.

FT9. Slope Stability, Extreme Floods, and Implications for Restoration in the Duluth Area.

Weds., 20 May, 8:45 a.m. –5 p.m. Cost: $40. Max.: 16 participants.

Emilie Richard, rich1726@d.umn.edu; Karen Gran, Univ. of Minnesota Duluth; Faith Fitzpatrick, U.S. Geological Survey; Marty Melchoir, Inter-Fluve.

Description: Geomorphic responses to extreme floods across the Upper Midwest have been dramatic and costly. The resiliency of stream restoration projects has been mixed. We will visit urban and forested streams in the Duluth area and northern Wisconsin with damages from culvert failures and mass wasting following floods in 2012 and 2018. From rock fall zones along near-vertical bedrock cliffs to rotational slumps in glacial sediments, few places in the Midwest offer such a variety of mass-wasting processes. We will tour several geologically unique and dynamic areas to discuss how slopes fail in the post-glacial landscape of Northeast Minnesota.

FT10. Duluth to Two Harbors—Transect through the Duluth Complex and Base of the North Shore Volcanic Group.

Weds., 20 May, 8 a.m.–6 p.m. Cost: $100. Max.: 22 participants.

Jim Miller, emeritus, Univ. of Minnesota Duluth, mille066@d.umn.edu; Terry Boerboom, Minnesota Geological Survey.

Description: This trip will profile the basal section of Mesoproterozoic (1.1 Ga) volcanic, intrusive, and sedimentary rocks that comprise the Midcontinent Rift (MCR) between Duluth and Two Harbors. After visiting the basal sedimentary and volcanic section of the MCR west of Duluth, we will focus the morning’s effort on the mafic intrusive rocks of the Duluth Complex. Outcrops along Skyline Parkway leading to downtown Duluth include exposures of the well-differentiated Duluth Layered Series and the overlying Anorthositic Series. In the afternoon, we will visit shoreline exposures between Duluth and Two Harbors that highlight various components of the North Shore Volcanic Group. These include pahoehoe- and aa-topped basalt flows, porphyritic basalts, flow-banded rhyolite flows, interflow sandstone units, and hypabyssal mafic sills. All of the stops are within 25 miles of Duluth and will require attendees to be able to traverse locally uneven terrain and steep slopes.

FT11. Sediments, Landforms, and Proglacial Lake History in Western St. Louis County, Minnesota.

Weds., 20 May, 7:30 a.m.–5:30 p.m. Cost: $95. Max.: 17 participants.

Jennifer McDonald, jmhorton@umn.edu; Kaleb Wagner, Minnesota Geological Survey; Andy Breckenridge, Univ. of Wisconsin–Superior.

Description: This trip explores sediments and landforms associated with the Laurentide Ice Sheet in northeastern Minnesota. Recent Minnesota Geological Survey mapping highlights the activity of the Koochiching lobe and the St. Louis sublobe. New varve records relate this activity to the retreat of the Rainy lobe from the Vermilion moraine.

FT12. Geologic Setting of the 1850 Ma Sudbury Meteorite Impact Layer on the Gunflint Trail, Northeastern Minnesota.

Weds., 20 May, 7:30 a.m.–Thurs., 21 May, 6 p.m. Cost: $285. Max.: 24 participants.

Mark Jirsa, Minnesota Geological Survey, jirsa001@umn.edu.

Description: Well-exposed examples of Archean, Paleoproterozoic, and Mesoproterozoic rocks contain and bracket the Sudbury Impact Layer. The stratigraphic top of Paleoproterozoic iron-formation is marked by shock-induced deformation and is overlain by ejecta that resulted from Sudbury meteorite impact nearly 500 miles to the east in Ontario. Participants will enjoy a night at the historic Gunflint Lodge on the Gunflint Trail.

Iconic rendition of Lake Superior with text: GSA North-Central, Duluth 2020, Superior Rocks.