Salutations!

Curious to learn if there is a recognized 'strongest magnetic anomaly point' in the BWCAW.
Is 'Magnet Rock' the strongest? Has anyone recorded other areas with equally or more baffling compass readings?

I thought it would be neat to 'see it for myself' & go to the best compass spinning spot the park has to offer.

As a piggy-back to this post, are there other phenomena that may be noteworthy to visit?
E.g. Puerto Rico has some unique/rare in nature bioluminescent bays. While I obviously don't expect anything like this in BWCAW, it is in the same vein of a unique display of nature that I am seeking.

Thanks!

PS
If ever you visit PR, I highly recommend visiting the bio bay. The bay on the SW side of the island is, imho, the best as it allows swimming in the bay - one of only a few places on earth where one can engage in this experience & it is awe inspiring. Cheers :)

The Devil’s Kettle is a natural anomaly. Not in the BWCA, but close by. As someone who seems to like swimming in the ocean, you might be surprised/pleased to know that there are jellyfish in the BWCA.

https://bwca.com/index.cfm?forumID=12&confID=1&threadId=275769&fuseaction=forum.thread

Link to thread

brp: "The Devil’s Kettle is a natural anomaly. Not in the BWCA, but close by. As someone who seems to like swimming in the ocean, you might be surprised/pleased to know that there are jellyfish in the BWCA.


https://bwca.com/index.cfm?forumID=12&confID=1&threadId=275769&fuseaction=forum.thread
"

Oh
my
God
...

This is amazing - I have to find out more.
Thank you very much, brp!

A friend and I definitely found a spot like that a couple years ago. I can't remember exactly which lake it was now, I'll have to check with him, but I'm pretty sure it was somewhere on Glee/Elusion/Glossy on the way to Paulson, which is south of Sea Gull. Both of our compasses were going nuts while paddling and it went on for a while.

Anyone else have a similar experience in that area?

That was a fun route, lots of solitude when we went through, which added to the creepiness of the compass thing. I think the 400 rod portage over the hill between Paulson and Sea Gull has something to do with that.

I thought I was seeing some magnetic anomalies this summer on a compass I mounted on my yoke. Then I realized two screws under the yoke were messing with the needle. Don’t make my mistake.

I was cruising timber just north of Isabella, my northern line/boundary went right through a rock outcropping. I could not get that line in for 3-4 hundred feet or more, my compass would not cooperate, after an hour I gave up. We had to come back with a Trimble GPS.

Here's a magnetic field anomaly map from the USGS. It shows magnetic field strength, rather than direction, but in places where there is a change in direction there should also be a strong anomaly in strength. I suggest using the web interface. You can toggle the anomaly shading on and off to find places of interest in the baseman underneath. There are some strong changes in strength north of Isabella and also around Seagull Lake.

Note that this data was collected by towing magnetometers behind airplanes and so very localized anomalies from smaller rock bodies near the surface may not show up well. The reason for doing that is it is efficient and also the very localized anomalies from near-surface features aren't as important for studying larger subsurface structure.

This may not really help you find the biggest local anomalies in the BW, but maybe it is fun data to explore.

andym: "Here's a magnetic field anomaly map from the USGS. It shows magnetic field strength, rather than direction, but in places where there is a change in direction there should also be a strong anomaly in strength. I suggest using the web interface. You can toggle the anomaly shading on and off to find places of interest in the baseman underneath. There are some strong changes in strength north of Isabella and also around Seagull Lake.


Note that this data was collected by towing magnetometers behind airplanes and so very localized anomalies from smaller rock bodies near the surface may not show up well. The reason for doing that is it is efficient and also the very localized anomalies from near-surface features aren't as important for studying larger subsurface structure.

This may not really help you find the biggest local anomalies in the BW, but maybe it is fun data to explore."

That is a really cool resource, thanks andym!