Ring Mold Craters are a kind of crater on the planet Mars, that look like the ring molds used in baking.
They are believed to be caused by an impact into ice.
 The ice is covered by a layer of debris.
 They are found in parts of Mars that have buried ice.
 Laboratory experiments confirm that impacts into ice result in a "ring mold shape."
 They are also bigger than other craters in which an asteroid impacted solid rock.
Impacts into ice warm the ice and cause it to flow into the ring mold shape.
Ring Mold Craters are a kind of crater on the planet Mars, that look like the ring molds used in baking. They are believed to be caused by an impact into ice.  The ice is covered by a layer of debris.  They are found in parts of Mars that have buried ice.  Laboratory experiments confirm that impacts into ice result in a "ring mold shape."  They are also bigger than other craters in which an asteroid impacted solid rock. Impacts into ice warm the ice and cause it to flow into the ring mold shape.
Ismenius Lacus quadrangle