Analysis of Surface Sound Duct in the Northern Shelf of the South China Sea

Table 2

Acoustic characters of duct cases.

	Case 1	Case 2	Case 4
Duct depth	43 m	7 m	6 m
Maximum grazing angle	4.65°	2.73°	8.35°
Minimum cutoff frequency	247 Hz	2591 Hz	840 Hz