Variable shade in ravines upset lean seabird (7,7)
I believe the answer is:
chinese lantern
'variable shade' is the definition.
'ravines upset lean seabird' is the wordplay.
'ravines' becomes 'chines'.
'upset' indicates anagramming the letters.
'seabird' becomes 'tern' (I've seen this before).
'lean' with letters rearranged gives 'elan'.
'chines'+'elan'+'tern'='CHINESE LANTERN'
'in' acts as a link.
(Other definitions for chinese lantern that I've seen before include "type of fruit" , "may throw some light on mandarins?" , "plant" , "Hanging, one doesn't give off much light" , "producing output of Asian light industry" .)