The results improve our understanding of the utility of tl as an indicator of sedimentary environment and provide insight into what types of ocean sediments are amenable for study . the comparison of the 18o with the tl cycles indicates that the tl dose display the expected coupling relation with interglacial and glacial climate cycles 尤以位于东经90海岭上的以远洋沉积作用为主的md81349岩芯最为理想,陆源剥蚀产物在其沉积记录中所占比例较少,有孔虫和超微化石为代表的远洋成因的灰白色生物软泥构成主要的沉积组分。