- 责任者：Zhou Kaisheng (Department of Applied Chemistry and Environmental Engineering ; Bengbu College ; Bengbu 233030 ; China) ; Meng Yi
- 刊名：Quaternary Sciences
- 出版年：2012
- 卷期：32(6)
- 关键词：海洋沉积物 ; marine sediments ; 沉积环境 ; sedimentary environment ; 长江口 ; Yangtze River Mouth
- 页码：p.1173-1182
- 图表：5 illus., 5 tables, 34 refs.
- 分类号：0200
- issnNo：ISSN1001-7410
- isbnNo：CN11-2708/P
The estuary of the Changjiang River is a kind of branching estuaries affected by the actions of tidal current.Chongming Dongtan is a geomorphology of tidal flat at the typical estuaine sand island edge.The samples acquired from the core DT（31° 32＇N,121° 57＇E） with the depth about 50m,located in the Changjiang River estuary in Chongming Dongtan wetland,in the year of 2007.Together got 215 samples for environmental magnetism,364 pieces of sample for particle size analysis,and 171 samples for foraminifera＇s analysis.With the analysis of the granularity and grain parameter size of the sediments of core DT in Chongming Dongtan,the sedimentary characteristics is elaborated since 13.0kaB.P.,refering to the characteristics of environmental magnetism,foraminiferal assemblages and its analysis parameters.With the regular pulses of hydrodynamic force reflected by the sedimentary characteristics,the core DT is divided into 7 sedimentary layers： layer 1（50～40m）,layer 2（40～35m）,layer 3（35～27m）,layer 4（27～17m）,layer 5（17～6m）,layer 6（6～2m）and layer 7（2m～0）.The regular pulses＇ changes in accordance with the sequence from layer 1 to layer 7 is weaker→stronger→stronger→weakest→strongest→stronger→weaker.According to the characteristics of its colors changed from the bottom up,the sedimentary environment taking turns from layer 1 to layer 3 is a reducing environment,while the sedimentary environment from layer 4 to layer 7 is an oxidation environment,and the oxidation from the bottom up gradually enhanced.Based on the comprehensive analysis of sedimentary environment of the core DT,and with the comparative analysis of core CY（in the North branch of Changjiang River estuary）and core Hm（in Nanhui district）at the same time,obtained the law of sedimentary environment evolution in the core DT of Chongming Dongtan,which reflected the sedimentary environmental evolution in the Changjiang River estuary.The law of sedimentary environment evolution is that seashore swamp-shallow sea→river estuary→delta front→pro delta→mouth bar→tidal channel→tidal flat from layer 1 to layer 7,from the Dongtan of Chongming,the Changjiang estuary.The rate of deposition from layer 1 to layer 5 is increasing gradually,though the rate of deposition from layer 5 to layer 7 is also increasing in general,layer 6 belows layer 5.