However, Black Sea Region researcher �zhan �zt�rk has said that Kerasous instead corresponds to ????? ( keras ) " horn " +-???? ( a place marker ), for the prominent horn-shaped peninsula that the city is situated on ( compare with the Greek name for the horn-shaped Golden Horn waterway in Istanbul, ????? ( Keras ) " Horn " ).
42.
I'm sure geologists place markers on the seabed, but as there isn't a general deep-water positioning system, they'll have to revisit those with a surveying ship periodically and determine their position individually ( with reference to the ship, and from there they can express that position in a general system like the GPS datum ) .-- Talk 00 : 24, 9 January 2010 ( UTC)