Drainage area comprised of twisted vines and briar (5,5)

I believe the answer is:

river basin

'drainage area' is the definition.

'twisted vines and briar' is the wordplay.
'twisted' is an anagram indicator.
'and' says to put letters next to each other (I've seen this in other clues).
'vines' after 'briar' is 'briarvines'.
'briarvines' anagrammed gives 'RIVER-BASIN'.

'comprised of' acts as a link.

(Another definition for river basin that I've seen is " Catchment area".)

I've seen this clue in The Independent.

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