Liesegang Rings in Southern Illinois
Nov 20, 2022 17:32:52 GMT -8
ecocentric, burntfoot, and 2 more like this
Post by driftwoody on Nov 20, 2022 17:32:52 GMT -8
I spent five days hiking around sandstone bluffs in Shawnee National Forest, mostly places I've been before over the years, but not all. Lots of impressive bluffs and nice views, but the highlights were details on the bluff walls.
The "rings" I encountered were of different shapes, often taking on the appearance of misshapen fractured rusty pipes or plates. The first examples below are from Rocky Bluff Trail near Crab Orchard Wildlife Refuge.
The Trillium Trail at Giant City State Park had some good ones too:
Liesegang rings may form from the chemical segregation of iron oxides and other minerals during weathering.[2] One popular mechanism suggested by geochemists is that Liesegang rings develop when there is a lack of convection (advection) and has to do with the inter-diffusion of reacting species such as oxygen and ferrous iron that precipitate in separate discrete bands which become spaced apart in a geometric pattern.[8] A process of precipitation known as the Ostwald-Liesegang supersaturation-nucleation-depletion cycle is known by the geologic community as a probable mechanism for Liesegang ring formation in sedimentary rocks.
The "rings" I encountered were of different shapes, often taking on the appearance of misshapen fractured rusty pipes or plates. The first examples below are from Rocky Bluff Trail near Crab Orchard Wildlife Refuge.
The Trillium Trail at Giant City State Park had some good ones too: