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世界闻名的大都市上海,在漫长的地质历史长河中,曾先后发生过五次遭海水吞没的悲剧。上海这块陆地的形成,自西(青浦和嘉定一线)向东(至南汇海滨),早则五六千年,晚则仅一二百年的时间。沧海桑田,这是地球发展的必然规律。因此人们担心,上海会不会再次沉沦成为海洋?从地球发展历史看,答案当然是肯定的。问题是上海第六次海浸何时到来?这是一个值得很好研究的大问题。要回答这个问题,我们还得追溯到二三百万年之前。根据地质学的研究成果表明,在最近二三百万年来,上海就曾几度出现海陆的交替变更。上海曾是扬子古陆的一部分。在三百多万年前,由于西南方向的印度半岛向北漂移,挤迫亚洲大陆,东边的太平洋海底则向西挤压,曾广泛隆起成为陆地,并有多次火山爆发,喷出大量的玄武岩流。
The world famous metropolis of Shanghai, in the long geological history, there have been five tragedies engulfed by the sea. The formation of this land in Shanghai, from the west (Qingpu and Jiading line) to the east (to Nanhui beach), as early as five or six years, but only a couple of hundred years later. Sea and sky, this is the inevitable law of the development of the earth. Therefore, people are worried that Shanghai will once again sink into the oceans? Judging from the history of the Earth’s development, the answer of course is affirmative. The question is when will the sixth Shanghai sea scandal arrive? This is a big issue deserving a good study. To answer this question, we have to go back two or three million years ago. According to the results of geology research shows that in the recent 23 million years, Shanghai, there have been several alternations of land and sea changes. Shanghai was once part of the Yangtze ancient land. More than three million years ago, as the south-west Indian Peninsula drifted northward and crowded the continent, the eastern seabed of the Pacific squeezed westward. It had been extensively uplifted to land and had many volcanic eruptions that spilled lots of Basalt flow.