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Several geologists accompanied the army of Napoleon Bonaparte that landed in Egypt in 1798 – indicating that perception of the military value of geology is almost as old as Earth science itself.     

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Does geology affect the tastes of wine, beer and whisky? and if so, how and by how much in each case?     

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The last decade has seen a complete revision of the sedimentary environment, stratigraphic sequence and structural history of the early Ordovician Manx 'Slate' Group of the Isle of Man .     

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The fossil record contains many examples of the interactions that occurred between organisms. Thus, Cenozoic molluscs are commonly found encrusted by bryozoans, serpulid worms and balanid barnacles; ancient scleractinian corals and echinoderms may show unusual growth patterns as a response to organisms that have embedded themselves into the host's skeleton; fossil bones can preserve indications of biting, gnawing and trampling; and ancient leaves may retain traces of bite marks and leaf miners. Other evidence of interactions may be more cryptic or difficult to interpret, none more so than the evidence of ancient parasitism.     

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Over the past decade, planets have been discovered that orbit other stars, a vast ocean has been detected below the icy crust of Jupiter's satellite, Europa, and fossils have been reported in a rock from Mars. On Earth, micro-organisms have been identified that inhabit environments previously thought to be too inhospitable to support life. All these observations have helped to define the interdisciplinary subject that has come to be known as astrobiology.     

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NASA lander Opportunity is achieving something that no previous planetary explorer has ever managed: field mapping and logging of exposed bedrock on another planet, in the Terra Meridiani (the Land of the Meridian) of Mars.     

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Numerous world class mineral deposits make the Kola Peninsula a 'Mecca' for mineralogists, and key economic deposits make it one of Russia's most important industrial areas. For geologists there is the challenge of explaining how this situation has come about.     

甘肃省夏河县隆瓦寺院金矿地质特征及找矿前景分析

隆瓦寺院金矿为多期活动的断裂构造和中酸性脉岩双重控矿的蚀变岩型中型金矿床,矿区内的多条矿化蚀变带,具有宽度大、走向延伸较稳定的特征。通过对该成矿特征及成矿条件分析,该矿体形态较简单,总体厚度变化较稳定,品位变化不太均匀。矿体的形成主要受一套浅变质碎屑岩建造、断裂构造及中酸性侵入岩脉的控制。该矿有利的成矿条件和特定的成矿类型对该地区的找矿具有重要指示意义。     

脉动压力的紊流分形特征

通过对脉动压力信号时间序列的分析证实了紊流的分形特征.首先,计算脉动压力信号时间序列的关联维数,并将其与动力系统相空间中图形结构的维数联系起来.分析表明,关联维数D_C随嵌入空间维数的不断增大而逐渐趋于定值6C<7,从而证明了相空间中稳定、低维吸引子的存在,也即证明了紊流内在有序性的存在.其次,用线截法从压力信号推求等压面的维数,发现等压面维数随不同压力值的分布与压力脉动的概率密度分布一致,概率密度越大,等压面维数也越高,且等压面的分形特性是局部存在的.     

Feature: The Great Whin Sill

Without question, many of the principles of geology as a science evolved as the rock outcrops of Britain were explored and discussed with an open mind. Nowhere can this be better demonstrated than in the history of opinion concerning the Whin Sill in the north of England.     

陕西彬长矿区煤层气赋存特征及资源利用

利用已有的地质成果,对陕西彬长矿区煤层开采中的瓦斯问题进行了讨论,就影响矿区煤层气富集的各种地质因素进行了分析,总结煤层气富集规律,提出先期抽排的可行性和今后工作意见,为煤炭资源开发中降低瓦斯含量、减少灾害发生找寻新的途径.     

热液成矿分带的自孤子特征

在研究了银山和铜厂等矿床分带规律的基础上,总结出热液成矿分带特征,并应用非线性科学中的自孤子理论定性地给出了热液成矿系统的属性, 指出热液成矿系统是活性扩散系统,热液矿床是活性扩散系统中的自孤子, 热液成矿分带具有静态径向对称自孤子特征,是嵌套式径向对称目标斑图.利用具体的反应-扩散方程模拟出的结果加以验证.     

宁乡县云影窝含金刚石钾镁煌斑岩地质特征

宁乡云影窝地区,共发现钾镁煌斑岩体27个,其中岩管6个。可分为岩浆型和火山碎屑型两个岩相,金云透辉橄榄钾镁煌斑岩、透辉金云橄榄钾镁煌斑岩及钾镁煌斑岩质火山角砾岩、钾镁煌斑岩质碎屑角砾岩四种类型.Ⅰ、Ⅱ、Ⅴ号岩管含微粒金刚石。共发现××颗。这一发现,标志着湖南原生金刚石普查找矿已取得重大进展。     

隧道超欠挖断面轮廓分形特征

对于极不规则的隧道围岩超欠挖轮廓,分形几何无疑是一个新思路。在测量数据的基础上,应用分形几何来定量描述围岩超欠挖轮廓线,表明隧道各类围岩的超欠挖曲线具有自相似性。在此基础上,进一步分析了各类围岩超欠挖曲线的分形维数与围岩类别之间的关系。研究表明,隧道围岩超欠挖曲线分形维数能较为直观地反映围岩类别,但其并不随着围岩类别的变化而呈线性变化;对于洞径一定的隧道,围岩超欠挖曲线的分形维数更能反映岩体结构和洞轴线之间的关系,这为准确预测掌子面前方围岩超欠挖情况奠定了理论基础。     

纹理特征在Aster影像数据分类中的应用

利用灰度共生矩阵的多光谱影像纹理分析的方法,实现了利用k-mean算法对Aster影像数据进行分类,并对基于单波段影像纹理的分类结果、单纯光谱信息分类结果和结合基于主要波段影像纹理的分析方法及在分类过程中结合掩膜等技术所得纹理特征影像分类结果进行比较。     

A Complex Prognostic Feature of Dangerous Atmospheric Events

Doklady Earth Sciences - A complex prognostic feature of dangerous atmospheric phenomena like hurricanes, squalls, and strong thunderstorms is proposed. It is based on the analysis of joint...     

中国现行海底地理实体通名术语存在问题辨析

由于我国海底地理实体命名工作起步晚,实践基础薄弱,翻译和编写的海底命名规范中的有个别通名术语定义存在争议,本文结合国内权威地质辞典和相关标准进行探讨,得出以下结论:1 Shoal是顶部覆盖松散沉积物的暗礁,会对船只航行构成威胁,建议翻译为"暗沙"。Bank是表面相对平坦的海底高地,不对船只航行构成威胁,建议翻译为"滩"或"浅滩"。2建议参考国际海底命名委员会(SCUFN)颁布的《海底地名标准化》(Standardization of undersea feature names,又称B6文件)(IHO and IOC,2008.),以1000m高差作为海山和海丘的分界,并且不对Hill(Abyssal hill)和Knoll作进一步区分,均称为海丘。3现有辞典对Canyon和Sea valley(Submarine valley)的翻译和定义可以沿用:Canyon译为海底峡谷,Sea valley(Submarine valley)译为海(底)谷,两者主要的区别在于横切面形态,而与规模无关。建议将Sea channel(Submarine channel)译为"海底水道",不仅与当前学术界的主流译法一致,而且易于与海底峡谷和海底谷区分。4 Plateau译为海底高原和海台均可,且两者并没有地貌等级差别,建议《海底地名命名》作相应修正。     

川北地区铀成矿特征与成矿预测

川北地区是我国南方重要的砂岩型铀矿成矿带之一.文章通过区域地质背景和典型铀矿床研究,总结了该区的铀成矿规律,厘定了砂岩型铀矿区域预测要素.根据预测要素构置了区域预测变量,并应用特征分析法圈定18片预测区,为今后的总体找矿部署提供科学依据.     

西藏亚贵拉铅锌多金属矿床的地质特征

西藏亚贵拉铅锌多金属矿是目前西藏地区最大的层状沉积型铅锌多金属矿床.该矿床产出的大地构造位置独特.成矿地质条件良好.本文从含矿建造、断裂构造、岩浆岩特征及其对成矿的控制作用分析入手,分析研究了矿体特征、矿石组构特征及围岩蚀变,揭示了亚贵拉铅锌多金属矿床的形成经历了晚古生代海底热水喷流沉积成矿和喜山期岩浆热液叠加成矿两期成矿作用,是典型的海底喷流沉积-岩浆热液叠加改造型铅锌多金属矿床.