PREDICTION OF SAND MOVEMENT NEAR PORT OF KANAZAWA

The accumulation of large quantities of sediments in the port of Kanaz awa prevents smooth navigation every year. To find the directions of t he sand movement and the sedimentary sources of littoral drift of sand in the port of Kanazawa, the methods of the ratio matching and gradie nts of kilo count number per second per weight of each element are app lied after analyzing geochemical elements in sand samples. According t o the correlation numbers obtained from the ratio matching, three kind s of sediments were found near the port, two of which were found in th e port. The first kind of sediment is transported by the stationary, s trong ocean current, which flows along the coast from the southwest to the northeast. These advected sediments accumulate near the tip of th e breakwater because of the decrease of current velocities due to the blocking effect of the breakwater. During the winter season or during storms with incident waves of high amplitude, the accumulated sediment s intrude into the port. The second and third kinds of sediment are co nveyed into the port along the beach by the back flows of the ocean cu rrent. The back flows are caused by the interaction of the strong ocea n current with the long breakwater. The historical coastal change near the port of Kanazawa following the construction of the long breakwate r is estimated using the present results.