【摘要】 黄海南部海底分布有钙质砂岩砾石（以前被误认为是钙质结核）,由45%的碳酸盐和55%碎屑组成,基底式胶结.原岩为陆相半咸水沉积.砾石与现代贝壳和淤泥赋存在一起,是搬运不远的原地残积.¹⁴C年代为19978±356年,形成于晚更新世晚期.岩石的研究指出,2万年左右海退时,黄海大都为陆地,海岸线在124°线以东,海退持续时间达1万年以上.更多还原

【Abstract】 Fragmented calcareous sandstone makes up almost 30-40% of a grabbed surface sample from station 8424 in the southern Yellow Sea (Fig.1) in Des. of 1984. Remainder of the sample is composed of grey mud, silty sand, fine sand, shells, and some clayey-limonite nodules.The sandstone is light grey in colour, and is flat oval, long-narrow strip or nodular in shapes. It consists of elastics and carbonate, the former makes up 45% of it and the latter is 55%. The stone is in clastic texture and basal cementation (Photo 3). The carbonate is recrystallized calcite, with high transparency, allotriomorphic granular, 0.05-0.10mm grain size and clean surface.It is indicated, by chemical analysis of trace elements of Rb, K, B, GaSr, Ba, Cr, Cu, Ni, V and isotopic analysis of δ18O, δ13C, 87Rb and 86Sr and 87Sr, that the stone was formed in terrestrial brackish water and eroded by seawater later.The 14C age of the stone is 19978±356a. B. P, arid the sedimentation takes place in late-Late Pleistocene.The research on the stone shows that the Yellow Sea was mostly a landduring a regression about 20000 years ago and the coast-line lay east of 124E at that time. The period of regression is more than 10000 years.更多还原