Touch down by mistake in fallen earth and rock (8)
I believe the answer is:
landslip
'fallen earth and rock' is the definition.
I can't judge whether this defines the answer.
'touch down by mistake' is the wordplay.
'touch down' becomes 'land' (I've seen this in another clue).
'by' says to put letters next to each other.
'mistake' becomes 'slip' (a slip is a blunder or mistake).
'land'+'slip'='LANDSLIP'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for landslip that I've seen before include "Fall of earth, stones, etc down slope" , "Avalanche" , "Rockfall" , "Earth movement" .)