Zulu found in a deep gorge, initially staggering (7)
I believe the answer is:
amazing
'staggering' is the definition.
(I've seen this before)
'zulu found in a deep gorge initially' is the wordplay.
'zulu' becomes 'Z' (phonetic alphabet: alpha, bravo, charlie etc.).
'found in' means one lot of letters goes inside another.
'deep' becomes 'main' (both can refer to the sea).
'initially' indicates taking the first letters.
The first letter of 'gorge' is 'g'.
'a'+'main'='amain'
'z' going into 'amain' is 'amazin'.
'amazin'+'g'='AMAZING'
(Other definitions for amazing that I've seen before include "Prodigious" , "Very impressive" , "Causing wonder" , "description of Grace?" , "Astonishing, wonderful" .)