Dance with great skill where oil's found (9,4)

I believe the answer is:

discovery well

'where oil's found' is the definition.
(where oil is discovered)

'dance with great skill' is the wordplay.
'dance' becomes 'disco' (disco can mean a dance event).
'with great skill' becomes 'very well' (as in doing something very well).
'disco'+'verywell'='DISCOVERY WELL'

I've seen this clue in The Guardian.

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