Fig. 9. Maps of confusion index (CI) at depths of (a) 0 to 0.10, (b) 0.10 to 0.20, (c) 0.30 to 0.40, (d) 0.70 to 0.80, (e) 1.20 to 1.30, and (f) 2.50 to 2.60 m