Eccentric dispute in delta region (8)
I believe the answer is:
camargue
'delta region' is the definition.
(region by the Rhone delta)
'eccentric dispute' is the wordplay.
'eccentric' becomes 'cam' (an eccentric is a mechanical device such as a cam).
'dispute' becomes 'argue' (to argue something is to dispute or contest it).
'cam'+'argue'='CAMARGUE'
'in' acts as a link.
(Other definitions for camargue that I've seen before include "delta in France" , "Marshy area in S. France known for its wildlife" , "Wetland region of southern France" , "French Rhone delta region noted for white horses" .)