GD0138 SOUTH CHINA SEA GEOLOGICAL INVESTIGATION BY M/V “NAN HAI 503” IN AREA BOUNDED BY 21-39-59.4N 116-14-34.6E，21-42-06.6N 116-18-36.1E，21-42-06.9N 116-19-45.7E，21-38-15.6N 116-20-04.4E，21-36-11.6N 116-19-22.1E AND 21-37-50.3N 116-13-50.7E FROM 10 JUL. TO 10 SEP. SIGNAL LIGHTS AND SHAPES WILL BE EXHIBITED ADVISED TO AVOID GUANGDONG MSA CHINA