关键词: 古海岸线, 南海北部, 水深, 古溺谷, 珠江口, 海底沉积物, 广州湾, 北部湾, 砂堤, 贝壳

Abstract: In this article, the authors, after analyzing the data which were collected during an integrated marine geological investigation of the Northern shelf of the South China Sea, carried out in 1970-1978, especially on the sediment samples and echo Sounder, shallow stratigraphy profiles and Sidescan Sonar records, acknowledged that their knowledge on the features, divisions and geological significance of the- 50 m paleocoastline have been greatly improved.