### Clue: Quarry Etna? Ludicrous, according to geologists nowadays (10)
### Answer: QUATERNARY 
 ### Explanation: Definition: according to geologists nowadays
 **Anagram of**(…? Ludicrous) QUARRY ETNA.
Defn: …, ie. the current and most recent geological period, from about 2.5 million years ago to now.