Credit checks estimate evidence of impact (6)
I believe the answer is:
crater
'evidence of impact' is the definition.
(impact caused by a meteor)
'credit checks estimate' is the wordplay.
'credit' becomes 'cr'.
'checks' indicates putting letters inside (inserted letters are checked or controlled).
'estimate' becomes 'rate' (I've seen this in other clues).
'cr' enclosing 'rate' is 'CRATER'.
(Other definitions for crater that I've seen before include "Bowl-shaped hole in the ground" , "Volcanic depresssion" , "Hole left by explosion" , "Bowl-shaped mouth of volcano" , "big hole" .)