"Valley Floor Resetting" . . . . . . . . . "Colin Thorne" . . . "sediment passage" . . . . . . "Blue-Green Cities" . . . . . . . . . . . . . . . . . . . "Blue-Green cities" . . . . . . . . . . . . "Prof. Colin Thorne" . "1952" . "Colin Thorne" . .