Lightnews — Scholar-powered news

Eric Portenga @drericp.bsky.social · 6d

Very proud of my hometown! #Muskegon and west #Michigan are hidden gems of our region! #GreatLakes

www.mlive.com/environment/...

After 40 years and $84M in cleanup, Muskegon Lake comes off toxic list

Federal, state and local officials gathered to announce the formal delisting of Muskegon Lake from the Area of Concern program.

www.mlive.com

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Eric Portenga @drericp.bsky.social · 7d

Learned last week that EMU invites creation of Faculty research pages via Google Sites, so I had a go at creating a new page for all things #Geomorphology at #EasternMichiganUniversity (linking to the #Research page since the home page is my face). Updates ongoing

sites.google.com/emich.edu/ge...

Geomorphology @ EMU - Projects

Laurentide Ice Sheet Retreat from the Great Lakes Region, USA

sites.google.com

Eric Portenga @drericp.bsky.social · 21d

That feeling of hitting "Submit" on a revised manuscript after Reviewers suggest Minor Revisions 😎

More details soon!

#Geology #Geomorphology #EarthScience #QuaternaryGeology #Research

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Eric Portenga @drericp.bsky.social · 28d

The #EMU #EarthScience Support #Laboratory is getting a makeover! Unboxed our new jaw crusher, plate grinder, and ro-tap sieve shakers today! Soon, #geology faculty will be able to do mineral separation in house! Just waiting on the magnetic separator 🧲

🪨🪨🪨

A sieve shaker, rock jaw crusher, and gravel plate grinder still strapped to their shipping pallets in a geology lab space

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Eric Portenga @drericp.bsky.social · 29d

Just learned about the 1954 Prospect Point #Rockfall at #NiagaraFalls. Amazing video footage of the rockfall as it occurred, too. Caused by dolostone dissolution over time. Will have to incorporate into my #Geomorphology course this fall.

blogs.agu.org/landslideblo...

The 1954 Prospect Point Rockfall at Niagara Falls

Amazing archive footage on Youtube showing the 1954 Prospect Point Rockfall at Niagara Falls in USA, which had a mass of 168,000 tonnes

blogs.agu.org

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Eric Portenga @drericp.bsky.social · Sep 7

Amazing! What do you attribute that growth to? Any suggestions for programs trying to improve enrolments?

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Eric Portenga @drericp.bsky.social · Sep 6

Having grown to love #Australia during my time there in grad school, this is such good news!

Protected koalas? ✅
Cultural heritage led by Aboriginal rangers? ✅

Such great news! The world needs more new #NationalParks

🐨 🐨 🐨

www.abc.net.au/news/2025-09...

Announcement expected to lock in long-awaited Great Koala National Park

The long-touted Great Koala National Park is set to become a reality in New South Wales, protecting koala populations and other threatened species in the state's mid-north.

www.abc.net.au

Eric Portenga @drericp.bsky.social · Sep 5

Brave the wind, and come on down! Check out the #EMU #Geography and #Geology Department table at #STEM Night at #Ypsilanti Community High School! See if you can complete the Rock Cycle, make jolly rancher stratigraphy, and put a 📍 on the Quaternary Map of #Washtenaw County! #EarthScience

Geology professor standing behind the Eastern Michigan University booth at Ypsilanti Community High School STEM night

Baggies of crushed jolly rancher candy as stand-ins for sediment

Printout poster map of the Quaternary Geology of Washtenaw County, Michigan

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Eric Portenga @drericp.bsky.social · Aug 26

Happy #InternationalDogDay to Max, our derpy #dog, lover of #LakeMichigan, and occasional #fieldwork assistant. Unfortunately, he doesn’t have a good nose for finding #MichiganErratics

Portrait photo of beagle-lab mix sitting amongst leafy garden

Beagle-lab mix in the woods sniffing around a glacial erratic

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Eric Portenga @drericp.bsky.social · Aug 26

A former #EMU student doing #undergraduate #research worked with a massive SH and 10Be dataset from #erratics in #Wisconsin to construct a SH exposure calibration curve for the #GreatLakes region, but we ended up with a “negative result” dataset…currently in review. Hope to have it published soon!

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Eric Portenga @drericp.bsky.social · Aug 26

When Schmidt Hammer data are paired with #10Be exposure ages for #rocks, a calibration curve can be made. Ideally, Schmidt Hammer measurements can then be used to estimate rock exposure ages quickly and at cost. #geochronology

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Eric Portenga @drericp.bsky.social · Aug 26

No, I’m not testing #MichiganErratics for allergies. Dots are #SchmidtHammer measurements that reveal the relative hardness of #rock surfaces. Strong rock ➡️ short exposure; weak rock ➡️ long exposure. #geomorphology #geology #geochronology #GreatLakes

Large granite boulder positioned on a leafy forest floor. Moss is growing on one side and there is a series of small dots/markings on the boulder surface in a grid pattern

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Reposted by Eric Portenga

The Onion @theonion.com · Aug 25

Rock Looked Way Cooler Wet

230 2.7K 17K

Eric Portenga @drericp.bsky.social · Aug 25

When the going gets tough sampling super hard #rocks and you bend a solid steel chisel, you know it is time to call in help from #Wolverine! #MichiganErratics

#geology #earthscience #geomorphology #fieldwork #research #icesheet #Quaternaryscience #Michigan #GreatLakes

Surface of a glacial erratic with a scale bar, sample ID sign, and a steel chisel bent in half

Surface of a glacial erratic with three evenly spaced cuts in the rock, which looks like Wolverine from the X-men was here

Eric Portenga @drericp.bsky.social · Aug 24

Been back out in the field this week collecting nearly the rest of samples needed to date the Port Huron Moraine built by the Saginaw Lobe of the Laurentide #IceSheet. Hunting for #MichiganErratics in the “Thumb” of #Michigan has been hard because of centuries of farming and other land use

Large boulders moved by farmers to a rock pile at the edge of a forest along with a rusty old car

Eric Portenga @drericp.bsky.social · Aug 7

Struck out hunting for #MichiganErratics today, but got to explore a small old growth #forest with black maple, huge beech, and 200-year old hemlock trees at the Caro Airport. Yet another reason why the #GreatLakes are awesome! (Unfortunately, not open to public)

#EarthScience #Fieldwork #Michigan

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Eric Portenga @drericp.bsky.social · Aug 5

Thanks @tamarakeithnpr.bsky.social and @sarahmccammon.bsky.social for featuring my timestamp on the NPR Politics Podcast! Check out my feed for photos of #MichiganErratics (aka glacial rocks abandoned in the #GreatLakes when the Laurentide #icesheet melted) 🧊🪨🧐

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Eric Portenga @drericp.bsky.social · Aug 5

If you listen to the @npr.org Politics Podcast episode for today, you’ll hear yours truly reading out the timestamp, featuring #MichiganErratics and #EasternMichiganUniversity!

#geology #earthscience #fieldwork

podcasts.apple.com/us/podcast/t...

Trump's new tariffs set to take effect this week, but much is uncertain

Podcast Episode · The NPR Politics Podcast · 08/04/2025 · 17m

podcasts.apple.com

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Eric Portenga @drericp.bsky.social · Aug 2

Woohoo! First sample collected from the Port Huron #Moraine of the Saginaw Lobe of the Laurentide #IceSheet! How long ago? Guess we’ll find out in…oh…a year?! #Geology #Geomorphology #Research #MichiganErratics

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Eric Portenga @drericp.bsky.social · Jul 30

New #Geology & #EarthScience recruitment poster up in Strong Hall at #EMU. Hopefully this helps students decide to declare a Geo Major!

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Eric Portenga @drericp.bsky.social · Jul 26

Day 5: 🪨🪨🪨🪨🪨🪨🪨🪨🪨🪨

The first complete set of #MichiganErratics for my #NSF research project constraining Laurentide #IceSheet retreat through the #GreatLakes

1 down, 7 to go!

#Geology #EarthScience #Research #Michigan

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Eric Portenga @drericp.bsky.social · Jul 25

Day 4: Averaging 18,000 steps and covering hundreds of acres daily looking for #MichiganErratics. When I find them, I definitely don’t take them for granted (but they are #granite) 🪨

Ending my hunt on the Outer Port Huron #Moraine with this behemoth left as a gift by the Laurentide #IceSheet

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Eric Portenga @drericp.bsky.social · Jul 23

Day 3: @paul-bierman.bsky.social nice gneiss, eh? Migmatite send it your way in the first batch of #MichiganErratics! 🪨

#EarthScience #Geology #Rocks

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Eric Portenga @drericp.bsky.social · Jul 23

Day 2 of hunting for #MichiganErratics was less fulfilling…had to ask these turkeys if they knew were any were (they didn’t). At least I found a beautiful over the #ManisteeRiver at Eagle’s View, Springfield Twp. Park

Eric Portenga @drericp.bsky.social · Jul 23

Yesterday was Day 1 on the Outer Port Huron #Moraine (Lake Michigan Lobe) hunting for #MichiganErratics! Collected 4 samples

#Geology #LaurentideIceSheet #EarthScience #Michigan #GreatLakes