南黄海北部深水区表层沉积中有孔虫和介形虫的分布

DISTRIBUTION OF FORAMINIFERA AND OSTRACODA IN SURFACE SEDIMENTS OF THE NORTHERN SOUTH YELLOW SEA

南黄海北部深水区 (36°15 ～ 38°0 0 N、12 3°2 0 ～ 12 4°33 E)表层沉积中的有孔虫和介形虫主要由原地分子和残留分子组成。残留分子为陆相介形虫、沿岸浅水有孔虫和介形虫 ,反映了末次冰期低海面和冰后期海侵初期的沉积环境 ,原地分子以冷水和深水种为特征 ,介形虫以 Sarsicytheridea bradii、Acanthocythereis mutsuensis和Munseyella japonica等为优势种。有孔虫有两个组合 :东北部为以 Proteonina atlantica为代表的胶结质壳组合 ;西南部为玻璃质壳组合 ,其优势成分是 Buccella frigida、Protelphidium tuberculatum、Ammonia ketienziensis、H anza-waia mantaensis和 Pacinonion tasmanensis等。调查区埋葬群存在原地和叠加两种类型 ,前者分布在北部和南部 。

Ostracod and foraminiferal relict elements have been distinguished in terms of their preservation and ecological data in surface sediments of the deep water area of the northern South Yellow Sea(36°15～38°00N、123°20～124°33E,water depth 67 to 82m).The relict faunas consisted of non marine ostracoda and coastal foraminifera and ostracoda,and obviously formed during the last glaciation and at the beginning of the post glacial transgression.The autochthonous faunas were characterized by cold water and deep water species.The ostracod fauna was dominated by Sarsicytheridea bradii,Acanthocythereis mutsuensis and Munseyella japanica. The autochthonous foraminiferal fauna can be divided into two assemblages:the agglutinated assemblage of the northeastern area dominated by Proteonina atilantica and the hyaline assemblage of the southwestern area mainly composed of Buccella frigida,Protelphidium tuberculatum,Ammonia ketienzienses,Hanzawaia mantaensis and Pacinonion tasmanensis. The autochthonous and superimposed thanatocoenosis have been recognized based on their compositions.The autochthonous one consisted of autochthonous elements and mainly found in the northern and southern areas,and the superimposed thanatocoenosis was composed of both autochthonous and relict elements and distributed in the central and western areas.