A maar is a shallow volcanic crater with steep sides that is surrounded by tephra deposits. The tephra deposits are thickest near the crater and decrease with distance from the crater.
I have looked at about 70 craters formed by this type of explosion. I have gathered several data points such as diameter, depth, and elongation. I am now trying to use this data to attempt to find this type of crater in some regions of Mars.
Earlier attempts have ended in failure. Mainly because I am mistaking maar craters with supervolcanos, and impact craters with maars, and vice versa. The craters that I have looked at are very young. Mars's volcanic activity is believed to have ceased many billions years ago.
What are some good ways to identify this type of geologic feature from other potential doppelgangers? I have no data points for old maar craters mainly because they are too eroded to measure anything, and/or have large scoria cones that have erased their once-elliptical shapes.