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ＡｎａｌｙｓｉｓａｎｄｓｔｕｄｙｏｆｔｈｅｌａｒｇｅｅａｒｔｈｑｕａｋｅｒｉｓｋｉｎＹａｎｑｉｎｇＨｕａｉｌａｉｂａｓｉｎＣＨＡＮＧＱＵＡＮＬＩＵ（刘昌铨）ＳＨＩＸＵＪＩＡ（嘉世旭）ＭＩＮＧＪＵＮＬＩＵ（刘明军）ＣＨＡＮＧＦＡＬＩ（李长发... 相似文献
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黄龙的景观是在数万年的岩溶地质作用下的产物。近年来黄龙钙华出现了干涸、变黑、沙化等现象严重地影响了景观的观赏性。水资源在黄龙钙华发展变化中起着重要的作用，笔者通过收集并分析黄龙地区的监测数据，针对监测系统不健全．时序数据缺乏的特点，选用对时序数据要求不高、预测效果较好的灰色系统模型，以岩溶水体的pH值为指标预测了钙华未来的发展情况。采用地质统计学空间分析的克里金插值法，对预测结果进行插值获得了整个景区的钙华预测结果。笔者按pH值将钙华演化情况划为强侵蚀、弱侵蚀、堆积3种类型，指出黄龙钙华景观目前正处于动态平衡与消亡重组阶段。 相似文献
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鲁武马盆地古近系-新近系发育多套超深水、超大型、富含天然气藏的重力流沉积砂体。以始新统砂体为解剖对象,分析区内重力流砂岩储层特征及成因。结果表明砂体以巨厚层状产出于深海泥岩内部,并与周围泥岩截然接触,测井曲线表现出宏观均一性;岩心揭示此类巨厚砂体是由多期单砂体叠置而成,单砂体是由底部高密度颗粒流和顶部低密度浊流两部分组成,且经历过强底流改造。鲁武马河流三角洲强大物源供给决定了区内砂体分布面积和体积规模;深海滑塌、块体搬运等重力流沉积过程控制了沉积体粒序构造和内部结构;海底区域性强底流持续冲刷并携带走单砂体顶部细粒沉积物,残留了底部“干净”的中粗粒砂岩;多期沉积事件和频繁水道迁移决定了砂体纵、横向叠加展布,并最终形成了区内厚度巨大、岩性宏观均一且连通性极好的超大型深水重力流沉积砂岩储层。 相似文献
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在城市测量中,由于建筑物的不断增高,绿化植物的多样与浓密,仅仅利用GPS-RTK无法完成一项测量工作,必须与常规测量相结台才行.为此,本文采用GPS-RTK与边角交会联合测量图根控制;并介绍了GPS-RTK与常规的边角变会相结合测图根控制的施测、检核及计算方法,分析了交会点的点位精度;最后通过算例得出几点有用的结论. 相似文献
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Saber Al-Rousan Mohammed Rasheed Fuad Al-Horani Riyad Manasrah 《Journal of Oceanography》2006,62(6):839-849
The physicochemical properties of 21 marine sediment samples were investigated, collected from five different localities along
the Jordanian coast of the Gulf of Aqaba. According to the chemical parameters, sediments were categorized into three groups:
carbonate (80% CaCO3), composed mainly of materials of calcareous skeletal structures; terrigenous (<10% CaCO3) depositional areas for land-derived materials from surrounding rocks and alluviums; and a admixture of the first two (19–37%
CaCO3). High significant linear correlations were found between organic carbon (OC) and total nitrogen (TN), indicating the occurrence
of these components in a common phase (organic matter). Despite the co-occurrence of TP in organic matter, these two elements
were negatively correlated, indicating anthropogenic sources of pollution such as phosphate exportation (hotel areas and clinker
port sites) and industrial activities (industrial complex site). The study found that variations in texture properties and
mud contents were due to differences in sediment sources, topography and their response during currents and waves. The finer,
well-sorted sediments contain lower elemental concentrations of OC, calcium carbonate and TN (excluding TP) than coarser,
poorly-sorted sediments. 相似文献
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This paper discusses the origin and development of the Zhujiang Delta on the basis of the analyses of the fault systems, lithofacies, depositional thickness, ancient coastline and 14C dating. We consider that the delta is a multi-faulting block, whose external form, internal structure and configuration of its ancient coastline are all strictly controlled by three active sets of the NE, NW and WE faults. 相似文献
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Saber Al-Rousan Rasheed Al-Shloul Fuad Al-Horani Ahmad Abu-Hilal 《Environmental Earth Sciences》2012,67(7):2003-2013
The concentrations of six heavy metals were studied in five living coral species and their fossil counterparts collected along the Jordanian Coast of the Gulf of Aqaba. The study aimed at investigating the validity of using coral skeletons as bioindicators for environmental pollution by heavy metals in the Gulf of Aqaba, Red Sea. The skeletal samples of the collected corals were acid digested and analyzed for Cd, Cu, Fe, Mn, Pb, and Zn content using flame atomic absorption spectrophotometer. The results obtained have shown that higher concentrations of heavy metals were found in coral skeletons from areas hosting intense developments and human activities. The massive Porites sp. coral tended to accumulate the highest metal concentrations among the other species (except for Mn). This was due to interspecific differences or selectivity of heavy metals between different coral species. It was noteworthy that fossil coral species recorded higher average metal concentrations than their living counterparts; this was attributed to surface contamination due to prolonged burial of the fossil corals in sediment over the years. The study concluded that corals (specially the massive Porites species) are vulnerable to the accumulation of high concentrations of heavy metals in their skeletons and therefore can serve as proxies to monitor environmental pollution. 相似文献
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推导出方向后交点住精度的显函数公式;用解析法导出对称交会时最佳交会角和最佳点精度;用无约束最优化共轭梯度法,求出一般情况下方向后交最佳交会角和点位精度;求出同一三角形三个内角分别作顶角进行后交定位的最佳点位,得出三角形内只有一个最佳点位的结论,给出一种选择近似最佳点位的方法. 相似文献