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“北京人”遗址洞穴堆积物的研究,已有五十多年的历史。多方面的研究成果,也先后报道。近年来,作者分层测制了周口店第一地点西壁、南壁、探井以及上砾石层和下砾石层等几个剖面。还在周河口、羊耳峪东岭、三福村采集样品55个。所有样品均进行筛分,分级进行镜下鉴定,单矿物系统折光率测定,个别矿物辅以X-射线分析,分别对轻、重组份物质成分、百分含量做了系统计量,并着重研究重组份特征。本文是在这些工作基础上,对这一地区的地层划分、沉积物来源和古气候变迁等进行讨论。 一、物质来源和蚀源母岩 野外观察和沉积矿物成份分析表明,第一地点洞穴堆积有洞壁崩塌和外部携入两个来源。碳酸岩角砾和碳酸岩岩块大量出现,在特定层位尤其发育,它们是洞壁崩塌的产物。外来物质尽管矿物含量时有变化,但矿物种类大体相近,构成不同矿物组合。轻组份有石英、酸性斜长石、微斜长石、白云母组合,千枚岩、角岩、板岩岩屑组合以及滚圆状石英、石英岩、硅质岩岩屑组僵。重组份相应出现普通角闪石、磁铁矿、褐铁矿、榍石、晶形良
The research on the burial deposits of “Beijingers” site has been more than fifty years old. Many research results have also been reported. In recent years, the author has stratified and measured several sections such as the west wall, south wall, exploration well, upper gravel layer and lower gravel layer at the first place of Zhoukoudian. In Zhouhekou, Yanglingyu Dongling and Sanfu Village, 55 samples were collected. All samples were screened, graded for microscopic identification, refractive index of single mineral system, individual minerals supplemented by X-ray analysis, respectively, light and heavy components of the material composition, the percentage content of a systematic measurement, and focus on the reorganization Features. Based on these works, this article discusses the stratigraphic division, source of sediments and paleoclimate changes in this area. First, the source of material and eclipse Source rock observation and sedimentary mineral composition analysis shows that the first deposit cave cave wall collapse and external carry two sources. Carbonate breccias and carbonate rocks occur in large numbers and are especially developed at particular levels, which are the product of wall collapse. Foreign matter Although the mineral content changes, but the mineral types are generally similar to form a combination of different minerals. The light components include quartz, acidic plagioclase, plagioclase, muscovite assemblage, phyllite, hornfels, slate cuttings assemblages, and rounded quartz, quartzite and siliceous cuttings. Accordance with the corresponding general amphibole, magnetite, limonite, stone, crystal form good