Indiana Jones perhaps loathes a corgi barking (13)
I believe the answer is:
Here is my best explanation:
'indiana jones perhaps' is the definition.
I can't tell whether this definition defines the answer.
'loathes a corgi barking' is the wordplay.
'barking' is an anagram indicator (UK slang for mad).
'loathesacorgi' is an anagram of 'ARCHAEOLOGIST'.
(Other definitions for archaeologist that I've seen before include "Excavator of the past", "One studying past things", "One who studies past human life through excavation and analysis of artefacts", "One studying relics from the past", "Excavating historian", "Antiquarian", "One excavating history", "One looking to the past", "One studying ancient peoples" and "Ancient digger".)