Comments on: Lester Park Stromatolites

By: Greg Laden

Greg Laden — Wed, 30 Mar 2011 13:11:01 +0000

scidog: I agree. Are you a member of the Minnesota geology society? They show up at the State Fair (ed building) every year.

By: scidog

scidog — Wed, 30 Mar 2011 06:43:51 +0000

Greg..when you said Lester Park i was thinking of the one near Duluth and hoping that the geology of Minnesota was going to get some hype.i have a passing interest in “rocks” and paddling around the lakes up north see some very interesting stuff.not just the glacial leavings but what the guide books call roots of mountains.looking thru the web it’s hard to find any detail and places like Highly Allochthonous seem to que in on the South West and the exposed sides of mountains.before i run on too much the point was that we have some incredible geology in the exposed “roots” up north that does not seem to get much attention.

By: Greg Laden

Greg Laden — Wed, 30 Mar 2011 02:26:15 +0000

NJ: Good point. Since I deal mainly with fossils, the hot end of the scale is not exactly my bailiwick. Duly noted.

Benton: I’ve heard of them. Different basin, maybe a different (slightly younger?) age. I haven’t quite made it to the gunflint trail area yet for more than a drive through.

By: Benton Jackson

Benton Jackson — Wed, 30 Mar 2011 02:18:43 +0000

You can see Stromatolites in MN. On the Magnetic Rock Trail, off the Gunflint Trail, in the BWCA. They’re not very common, but they’re around.

By: NJ

NJ — Wed, 30 Mar 2011 02:03:42 +0000

OP:

Personally, I think it might be diagenesis concentrated along joints or fissures of some kind, where hot gasses were allowed to mingle with rock under great pressure, deep below the surface of the earth in the depth of time.

{begin petrologic pedantry}

Diagenesis refers to the alteration and lithification of sediments at relatively low temperatures and pressures. What you are describing is best referred to as hydrothermal alteration.

{end petrologic pedantry}

By: jonquil

jonquil — Wed, 30 Mar 2011 01:35:13 +0000

I can remember playing hopscotch with my cousins on the fossils. There’s one place where it really looks like a hopscotch pattern. To the west of Lester Park, Howe Cavern is fantastic place to visit as well. They used to have boats to take you through on a tour. Lester and Howe make a really nice three day weekend trip.