CAJ | 학술논문

本研究通过对长江口现代潮滩6个柱状样沉积物的粒度精细分析，试图提取研究区潮滩沉积相识别的粒度敏感指标，并通过对长江三角洲南部平原一个全新世钻孔（SL67孔）潮滩沉积物的粒度研究，检验现代沉积粒度敏感指标在全新世钻孔潮滩沉积相识别中的应用。研究显示，长江口现代高潮滩和中潮滩的黏性颗粒（＜8μm）和粗粉砂（32～63μm）含量差异显著，可以成为区分高潮滩和中潮滩的敏感组分；在开敞型的中、低潮滩之间，砂（＞63μm）和细粉砂含量（8～32μm）也差异明显。长江口现代潮滩沉积物的粒度频率曲线及众数值也可以有效协助区分高潮滩、中潮滩和低潮滩沉积物。利用上述粒度敏感组分和众数指标检验 SL67孔全新世早中期在海平面波动控制下的潮滩演替过程，并揭示了7.5 cal ka BP前后的一次海平面加速上升事件。
본연구통과대장강구현대조탄6개주상양침적물적립도정세분석，시도제취연구구조탄침적상식별적립도민감지표，병통과대장강삼각주남부평원일개전신세찬공（SL67공）조탄침적물적립도연구，검험현대침적립도민감지표재전신세찬공조탄침적상식별중적응용。연구현시，장강구현대고조탄화중조탄적점성과립（＜8μm）화조분사（32～63μm）함량차이현저，가이성위구분고조탄화중조탄적민감조분；재개창형적중、저조탄지간，사（＞63μm）화세분사함량（8～32μm）야차이명현。장강구현대조탄침적물적립도빈솔곡선급음수치야가이유효협조구분고조탄、중조탄화저조탄침적물。이용상술립도민감조분화음수지표검험 SL67공전신세조중기재해평면파동공제하적조탄연체과정，병게시료7.5 cal ka BP전후적일차해평면가속상승사건。
This study takes detailed analyses on the sediment grain size for six cores from the modern tidal flats of Yangtze River mouth,to draw the diagnostic indexes for recognization of tidal flat facies in the study area.We also examined the grain size of a Holocene Borehole SL67 from the southern Yangtze delta plain so that to apply the sensitive indexes derived from modern sediments.Results demonstrate that the co-hesive sediment (<8μm) and coarse silt (32 ~63μm) could be the sensitive indexes for distinguis- <br> hing upper and middle tidal flats.Sand (>63 μm)and fine silt (8 ~32μm) components differ obvious-ly for the middle and lower tidal flats of open coast.Results also show that the parameter mode derived from grain size frequency curves is an effective index to help identify the upper,middle and lower tidal flat sed-iments.Above sensitive sediment components and mode were applied to identify the successions of tidal flat in Holocene Borehole SL67,which revealed the mechanism of sea level change and an acceleration of sea level rise around 7.5 cal ka BP.