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末次冰期后,在全新世大暖期及区域沉降的影响下,渤海湾沿岸普遍发育海侵现象,位于莱州湾南岸的潍北平原区在经历全新世最大海泛面后,海水退却过程中留下了数条古海岸线,形成了多处贝壳堤、牡蛎礁等海岸带遗迹。研究区内新发现常家村、后柳家2处牡蛎礁,其14C年龄分别为(5130±30)a B.P.和(6030±30) a B.P.;通过对区内全新世海陆交互相沉积关系及海相地层分布规律的研究,结合已有测年数据与近现代遥感影像数据,对潍北平原区全新世以来的海陆变迁进行了总结,恢复了自6000 a B.P.至公元1989年间的6条海岸线。 相似文献
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五龙金矿是辽东地区大型岩浆热液型金矿床,163矿脉是矿区内目前发现的最大含矿构造。为进一步探测深部找矿潜力,近几年矿山对163矿脉进行了大量的探采工程,其中在-762 m坑道实施了600 m钻孔。本文在详细编录该钻孔的基础上,对全孔样品进行成矿元素测试工作,利用SPSS软件对所得测试数据进行元素相关性、聚类、因子分析。相关性分析显示,具有显著正相关的元素主要为Bi、W、Cu、Ag、Au和As、Sb、Sn、Zn两组;Mo元素与Sn、Ag、Cu、Bi、W、Sb地素具有显著正相关性,而Pb元素与Cu、Mo、Au、W元素呈显著负相关性,Hg元素与其它元素相关性不明显。聚类分析结果表明,R型聚类在类的距离为5的水平上,这些元素明显可分为3组:Hg、Cu、Pb、Zn、Sn、Mo、As、W;Ag、Au、Sb、Bi。因子分析结果表明,提取3个因子可以反映出12个元素变量64.42%的地球化学信息,F1的主要载荷因子组成为Sn、Ag、As、Zn、Sb, F2的主要载荷因子组成为Au、W、Bi、-Pb, F3的主要载荷因子组成为Hg。根据成矿元素随深度变化特征,结合前人构造叠加晕研究成果,推测该钻孔深部还... 相似文献
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In this study radar, surface observations and numericalsimulations are used to examine the inland penetrationand intensity of the sea breeze during various large-scaleflow regimes along the curved coastline of the Carolinas,U.S.A. The results clearly indicate that the flow directionrelative to the curved coastline has a significant effecton the sea-breeze evolution.Overall, during northerly flow regimes alongthe curved North Carolina coast, observationsand numerical simulations show that the sea-breezefront has a tendency to remain close to the south-facingcoast. During these same flow regimes the frontmoves further inland relative to the east-facingcoast. The sea-breeze front during westerly flowcases progressed further inland relative to the southcoast and less so from the east-facing coastline.South-westerly flow allows the sea breeze to moveinland from both coastlines but the coastal shapeinfluence makes the inland penetration less fromthe easterly facing beaches. During periods of lightonshore flow (south-east), the sea breeze movesconsiderable distances inland but is not discernableuntil later in the afternoon. The simulations indicatedthat the sea-breeze intensity is greatest (least) when thelarge-scale flow direction has an offshore (onshore)component. Model results indicate the existence of astrong front well inland in the late afternoon duringlight onshore flow. Also noted was that the simulatedsea-breeze front develops earlier in the afternoon duringoffshore regimes and later in the day as the large-scaleflow becomes more onshore. It is concluded that thecoastline shape and coast-relative flow direction areimportant factors in determining how the sea-breezecirculation evolves spatially. 相似文献
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Spatial function regionalization and governance of coastal zone: A case study in Ningbo City 总被引:3,自引:0,他引:3
Reasonable development and utilization of spatial resources in the coastal zone not only affects the development quality of the marine economy but also impacts the utilization efficiency of spatial resources, playing an important role in regional sustainable development. Depending on the natural, economic, and societal characteristics of a region, research topics such as using relevant methods to divide the coastline, proper spatial development of the coast, protecting coastal zones, and achieving higher spatial resource distribution efficiency have recently become hot topics in geographic research. Most of the scholars construct the evaluation index system from the perspective of economic and ecological factors and undertake some exploration of the division methods. However, the selection of indicators for a coastal zone needs a different and more scientific approach. There is a need for emphasizing the overall strategy of land-ocean integration in developing spatial resources in a coastal zone. Taking the coastal zone in Ningbo as an example, this paper develops a new evaluation framework and spatial function regionalization method that is used to divide the coastline and coastal zone. Based on the perspective of overall strategy for the land and ocean, we evaluate the suitability of coastline development. We then propose the spatial function regionalization of the coastal zone. Finally, based on the status quo of spatial development in Ningbo, we divide the coastal zone into ecological space, production space and living space, and propose adjustment directions and control requirements for the different types of spatial layouts. 相似文献
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海岸线是分形领域最传统的研究课题 ,但是在目前的海岸线研究中却忽略了一个重要且根本性的问题 ,那就是海岸线分维数不同计算方法之间是否存在着一定的差异 ,根据不同计算方法计算所得的分维数之间是否具有可比性。在概述海岸线分维数计算方法的基础上 ,分析了它们之间的异同 ,并进行了实证研究。指出 :使用量规法、网格法计算所得海岸线分维数结果之间存在着客观的差异 ,文中利用量规法计算所得的海岸线分维数结果大于使用网格法计算所得的海岸线分维数结果。 相似文献