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笔者系统地研究了长江河口地区的晚第四纪地层。长江三角洲前缘区晚第四纪地层可划分为上更新统上段中部、全新统下部、全新统中部和全新统上部。上更新统顶部地层缺失。前三角洲区晚第四纪地层齐全,无缺失。武木冰期晚期,现今的长江河口和大陆架均出露成陆,古长江在大陆架外缘入海。15000aB.P,海面上升,海水逐渐向大陆架上部侵入;12000—10000aB.P,海水沿谷地侵入;6000aB.P,长江人海口在扬州、镇江附近。随着人类活动的增强,长江流域水土流失加剧,人海河口不断外移,并以南岸边滩推展,北岸沙岛并岸的形式使河口不断束狭,逐渐形成现今长江口三级分汉四口入海的态势。
The author systematically studied the Late Quaternary strata in the Yangtze River estuary. The Late Quaternary stratigraphy in the delta front can be divided into the upper part of the Upper Pleistocene, the lower part of the Holocene, the middle part of the Holocene and the upper part of the Holocene. The upper Pleistocene strata are missing. Late Quaternary stratigraphy in the former delta area is complete without missing. In the late period of the Mugu ice age, the Yangtze River estuary and the continental shelf are now exposed to the mainland. The ancient Yangtze River enters the sea on the outer edge of the continental shelf. 15000aB. P, sea level rise, the sea gradually invaded the upper part of the continental shelf; 12000-10000aB. P, sea water invades the valley; 6000aB. P, the Yangtze River estuary in Yangzhou, near Zhenjiang. With the enhancement of human activities, the soil and water loss in the Yangtze River valley intensified, and the estuarine estuaries shifted out continuously. The estuaries expanded on the south bank and the shore islands of the north shore sandstones continued to narrow the estuary and gradually formed the third- Four into the sea situation.