福建闽江河口长乐海岸发育大面积的具有典型风成沉积构造的风沙沉积,是海岸带过去风沙演变历史的良好记录材料。对长乐文岭风沙沉积剖面进行了野外考察和采样粒度实验,根据已有测年数据建立剖面的年代标尺,对剖面样品的粒度参数特征及...福建闽江河口长乐海岸发育大面积的具有典型风成沉积构造的风沙沉积,是海岸带过去风沙演变历史的良好记录材料。对长乐文岭风沙沉积剖面进行了野外考察和采样粒度实验,根据已有测年数据建立剖面的年代标尺,对剖面样品的粒度参数特征及其古环境意义进行分析。结果表明:(1)剖面样品以细砂、中砂和粉砂为主,粒度组成总体上偏粗,平均粒径和中值粒径呈现明显的峰谷值大小变化,说明风力作用总体上较强且强度有明显波动变化;(2)砂样粒度参数、概率累积曲线与内陆沙漠风沙相似,具有典型的风成砂特征;同时砂样粒度参数继承了海滩砂的某些特点;(3)从邻区各类沉积的叠覆层位关和绝对年代综合分析,文岭剖面可能跨越了全新世大部分时期,大约为10000年前到现代的风沙沉积;(4)文岭剖面记录的风沙环境历史可以初步划分为3个阶段,即:10000—8000 a B.P.风力作用强度大、波动幅度大;8000—2700 a B.P.风力作用较强、但波动幅度较小,反映较稳定的风沙环境;2700 a B.P.以来风力作用较弱,反映风力波动减小的趋势。展开更多
Considering the deviation in content of community detection resulting from the tow accuracy of resource relevance, an algorithm based on the topology of sites and the similarity between their topics is proposed. With ...Considering the deviation in content of community detection resulting from the tow accuracy of resource relevance, an algorithm based on the topology of sites and the similarity between their topics is proposed. With topic content factors fully considered, this algorithm can search for topically similar site clusters on the premise of inter-site topology. The experimental results show that the algorithm can generate a more accurate result of detection in the real network.展开更多
文摘福建闽江河口长乐海岸发育大面积的具有典型风成沉积构造的风沙沉积,是海岸带过去风沙演变历史的良好记录材料。对长乐文岭风沙沉积剖面进行了野外考察和采样粒度实验,根据已有测年数据建立剖面的年代标尺,对剖面样品的粒度参数特征及其古环境意义进行分析。结果表明:(1)剖面样品以细砂、中砂和粉砂为主,粒度组成总体上偏粗,平均粒径和中值粒径呈现明显的峰谷值大小变化,说明风力作用总体上较强且强度有明显波动变化;(2)砂样粒度参数、概率累积曲线与内陆沙漠风沙相似,具有典型的风成砂特征;同时砂样粒度参数继承了海滩砂的某些特点;(3)从邻区各类沉积的叠覆层位关和绝对年代综合分析,文岭剖面可能跨越了全新世大部分时期,大约为10000年前到现代的风沙沉积;(4)文岭剖面记录的风沙环境历史可以初步划分为3个阶段,即:10000—8000 a B.P.风力作用强度大、波动幅度大;8000—2700 a B.P.风力作用较强、但波动幅度较小,反映较稳定的风沙环境;2700 a B.P.以来风力作用较弱,反映风力波动减小的趋势。
基金Supported by the National Science and Technology Support Program of China(No.2012BAH45B01)the National Natural Science Foundation of China(No.61100189,61370215,61370211,61402137)the National“242”Project of China(No.2016A104)
文摘Considering the deviation in content of community detection resulting from the tow accuracy of resource relevance, an algorithm based on the topology of sites and the similarity between their topics is proposed. With topic content factors fully considered, this algorithm can search for topically similar site clusters on the premise of inter-site topology. The experimental results show that the algorithm can generate a more accurate result of detection in the real network.
