摘要:
长江是我国第1大河流,在其巨量的泥沙供给下形成了大型的三角洲沉积体系。前人已经对现代长江水下三角洲的沉积过程、沉积物运移规律进行了研究,并利用矿物学和地球化学等方法探讨了沉积物物质来源,并对晚第四纪以来的各种时空尺度的沉积作用与沉积过程进行了论述,对长江水下三角洲的沉积演化过程有了比较深入的认识。但对于一些涉及三角洲沉积与演化的重要问题还有待深入研究。目前,关于末次盛冰期的古长江三角洲是否存在仍有一定分歧;长江三角洲作为重要的"源—汇"转换地带,对其进行"源—汇"研究应放眼于长江流域—长江三角洲—东海陆架为整体的更大尺度上进行;人类对于河口三角洲的作用和影响已经愈发强烈,必须重视和加强河口三角洲沉积对人类活动响应过程的研究。随着海洋科技调查和研究实力的增强,要回答和解决这些问题必须逐渐统一调查手段与处理方法,使调查结果具有同一性、可比性,对河口三角洲进行更加精细的解剖。
Abstract:
A huge deltaic sedimentary system is formed out of the Changjiang River, the largest river in China with a large amount of sediment discharge. The previous studies have revealed the sedimentary process and mechanism of sediment transport in the present subaqueous delta, based on mineralogy and geochemistry. The source of Changjiang River delta and the sedimentary processes in different time and space scale since Late Quaternary are studied. Though the evolution of the Changjiang subaqueous delta is basically disclosed, there are still some critical problems to be solved. The existence of Paleo-Changjiang River delta in the Last Glacial Maximum remains in controversy. From the Changjiang River basin to the East China Sea, the subaqueous delta is the key link between the source and sink. In order to reveal the sedimentary geology within the whole area, including the Changjiang River basin, the subaqueous delta and the ECS, further studies must be carried out, and more attention should be paid to this question. In addition, human activities, of which the influence on the sedimentary process is getting stronger, must be carefully studied. It is recommended that more work be placed on the subaqueous delta with advanced marine survey techniques
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