Monthly Archives: May 2016

Geo-pic of the week: Fossiliferous mudstone

colorized

Above is a picture of loosely-consolidated, fossiliferous mudstone from the Midway Group: a group of near-shore marine rocks exposed in southwestern Arkansas.  The Midway Group was deposited in a variety of near-shore marine environments that were common in what is now Arkansas around 60 million years ago. The majority of the fossils pictured here are casts of a variety of sea snails (gastropods), but there are also oysters and tiny bryozoans (marine filter feeders).

 

To see more views of fossiliferous mudstone click here

Geo-pic of the week: Spring boxes

 

Spring cool storage colorized

Before the invention of electric refrigerators, blocks of ice in insulated wooden cabinets called “iceboxes” kept food from spoiling quickly in warm climates.  This required access to ice, which had to be hauled in from cold climates by boat, and wasn’t always available, especially in remote places.   The picture above shows a cool water spring that was modified long ago into a primitive kind of refrigerator. The structure is made of concrete.  When it was in use, it would have had a door to keep cool in and keep animals and insects out, as much as possible. 

Just like caves, cool water springs in Arkansas stay close to 56 degrees in the summer – the ambient ground temperature.  Anyone that’s spent a summer in Arkansas knows it gets oppressively hot.  Having a place you could store milk, eggs, and other perishables would certainly have come in handy.  You still come across these old structures if you spend a lot of time out in the woods around the state.  This one was photographed near Hot Springs, Arkansas, in the Ouachita Mountains.