Crazy Magpies choir's making earth-shaking records (13)

I believe the answer is:

seismographic

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'making earth-shaking records' is the definition.
I can't judge whether this defines the answer.

'crazy magpies choir's' is the wordplay.
'crazy' is an anagram indicator.
'magpies'+'choirs'='magpieschoirs'
'magpieschoirs' is an anagram of 'SEISMOGRAPHIC'.

Can you help me to learn more?

I've seen this clue in The Telegraph.

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