The senior Barringer was the first to seriously propose an impact origin for the crater that now bears his name.
In addition, samples collected from deep drillings into the lake bottom confirm the impact origin of the structure.
It is not clear whether they are of volcanic or impact origin.
Its meteor impact origin was first proposed and widely reported in 2002.
Originally thought to be a diapir (salt dome), an impact origin was first proposed in 1985.
The recent discovery of shatter cones and microscopic shock effects is reliable evidence for an impact origin.
We now know from direct laboratory examination of lunar craters that they are almost entirely of impact origin.
These types of rocks and features suggest an impact origin.
However, planetwide, the morphologic evidence for an impact origin rather than a volcanic one is not compelling.
All of the various topographic features observed in lunar craters indicates their impact origin.