Mafic, Ultramafic and Carbonatitic Dykes in the Southern Siberian Craton with Age of ca 1 Ga: Remnants of a New Large Igneous Province?

正Virtual absence of igneous complexes with ages between1.8 Ga and 0.8 Ga in southern part of the Siberian Craton allowed to Galdkochub et al.(2010)to formulate a hypothesis of long magmatic quiescence.Most reliable     

变泥质岩递进部分熔融作用的构造物理学效应

在南内华达岩基中,晚中生代花岗岩的侵位导致表壳岩广泛的变质及部分熔融,形成混合岩杂岩体。对伊萨贝拉湖南羊圈混合岩杂岩体构造的野外观测和应变测量表明：①变泥质混合岩和鹅卵石砾岩记录了类似强度的应变;②变泥质岩发生了递进部分熔融,表现为离羊圈花岗闪长岩岩体的距离越远,部分熔融程度越低;③随部分熔融程度的变化,变泥质岩的应变承载构造也逐渐从混合岩带的弱相承载构造（IWL）往强相承载构造（LBF）过渡;④在同岩浆构造作用中,浅色体的流变学性质与鹅卵石砾岩中泥质组分相当,为应变的主要承载体。该结果表明：在高级变质岩区中,部分熔融程度是否足够高及熔体能否形成互相链接的网络,是高级变质岩的流变学强度发生突降、深部岩石发生侧向流动的前提。     

斯洛文尼亚北部Macesnik滑坡的逐步防治措施

本文概述了斯洛文尼亚北部区域Macesnik滑坡的发育历史及其防治措施。1989年,Macesnik滑坡诱发于Sol’cava村的上部区域,随后滑坡体体积不断扩大。2005年,Macesnik滑坡己对多处民房和农场以及panoramic公路造成了严重威胁,滑坡体到Savinja河和Solcava村的距离仅为1000米。该滑坡体长约2500米,宽100多米,总体积200多万立方米。滑坡体深度并不是一成不变的：平均深度10～15米,坡脚区域由于被露出地面岩石阻挡,其深度达到30米。不稳定的滑坡块体由含水的强风化石炭纪物质组成。目前的活动滑坡处于宽350米、厚50米和总体积约为800～1000万立方米的古滑坡范m内。自2000年起,利用36个钻孔对Macesnik滑坡进行了勘查,其中,有28个钻孔安装了可用作压力计的测斜管：利用20个横剖面对表面位移进行大地测量监测,开展这些工作有助于进一步了解滑坡的成因和机理。所以,应该合理地规划滑坡防治工程,减缓滑坡运动,降低滑坡运动造成的危害。由于滑坡运动强烈（最大速度50厘米／天,平均速度25厘米／天）,所以,制定滑坡防治工程方案不同于20世纪90年代。2001年以后,在防治工程的第一阶段,幕本上完成了滑坡周边区域的地表排水工程（如地表排水明渠）,并定期维护。在防治工程的最后阶段,制定了计划,建立了把地下排水工程（如深排水沟）和抑制工程（如混凝土垂直竖井）相结合的方案,混凝土竖井起排泄滑坡积水的深水井的作用和阻止滑动面向表面滑动的销钉作用。根据滑坡体的长度及其纵向几何形状,可以把Macesnik滑坡分成若干段,并且应该按次序实施滑坡的逐步防治工程。2003年秋季,在Macesnik滑坡最上部800米长的区域开凿了3个平行的排水深渠（长250米,深8～12米）,有效地证明了上述方法。由于2004年滑坡运动速度减缓,便在滑坡区域开始建造两个宽5米、深22米的钢筋混凝土竖外,并于2005年初完工。在斯洛文尼亚,这种支护工程（区分道路工程）用于滑坡防治尚属首次。监测结果表明,滑坡位移速度己被完全降至每天1厘米以下。滑坡防治措施还包括进一步加同Macesnik滑坡中部区域的混凝土竖井和支护横穿滑坡的公路。在滑坡坡脚区域计划实施支护工程,防止滑坡休进一步移动,同时,在对Macesni滑坡采取国家重大规划期间,能够确定这种支护工程的类型。     

城市化与自然灾害—必须解决的问题

在全球自然灾害现象普遍增多的背景下,城市化区域内自然灾害的数量也在增加。通过分析发现,由于一系列主客观因素,俄岁斯的许多城市遭到自然灾害的严重破坏。本文研究探讨自然风险存在条件下城市建设的发展问题及其解决途径。     

書報述評

主要氣象要素,對於一般昆蟲之活動,究有若何之影響乎?本文特對此有趣味之問題,分為温度,濕度,降水,光及輻射,雲量,風,氣壓及大氣帶電情況等八項討論之,文中數噱,雖僅限某數種昆蟲,然吾人固可由此區區者,而窺得此問題之全豹也。(一)温度(1)温度與昆蟲遷移之關係。因温度之改變,蝗蟲幼蟲遂有成羣遷移之現象,為温度影響昆蟲浩動最佳之證明,惟開始遷移之温度,則因種類不同,而各有異。1921及1924年Cook以三個半月之時間用65誘導陷穽捕捉Nocturnal Lepidoptera,分拆各種氣象要素之影響,     

History and Progress of the North American Soil Geochemical Landscapes Project,2001-2010

In 2007,the U.S.Geological Survey,the Geological Survey of Canada,and the Mexican Geological Survey initiated a low-density(1 site per 1600 km2,13323 sites) geochemical and mineralogical survey of North American soils(North American Soil Geochemical Landscapes Project).Sampling and analytical protocols were developed at a series of workshops in 2003-2004 and pilot studies were conducted from 2004-2007.The ideal sampling protocol at each site includes a sample from 0-5 cm depth,a composite of the soil A horizon,and a sample from the soil C horizon.The <2-mm fraction of each sample is analyzed for Al,Ca,Fe,K,Mg,Na,S,Ti,Ag,Ba,Be,Bi,Cd,Ce,Co,Cr,Cs,Cu,Ga,In,La,Li,Mn,Mo,Nb,Ni,P,Pb,Rb,Sb,Sc,Sn,Sr,Te,Th,Tl,U,V,W,Y,and Zn by inductively coupled plasma-mass spectrometry and inductively coupled plasma-atomic emission spectrometry following a near-total digestion in a mixture of HCl,HNO3,HClO4,and HF.Separate methods are used for As,Hg,Se,and total C on this same size fraction.The major mineralogical components are determined by a quantitative X-ray diffraction method.Sampling in the conterminous U.S.was completed in 2010(c.4800 sites) with chemical and mineralogical analysis currently underway.In Mexico,approximately 66% of the sampling(871 sites) had been done by the end of 2010 with completion expected in 2012.After completing sampling in the Maritime provinces and portions of other provinces(472 sites,7.6% of the total),Canada withdrew from the project in 2010.Preliminary results for a swath from the central U.S.to Florida clearly show the effects of soil parent material and climate on the chemical and mineralogical composition of soils.A sample archive will be established and made available for future investigations.     

蒙古中部巴彦洪古尔蛇绿岩带乌兰布拉格新块状硫化物矿床

The Bayankhongor ophiolite zone, a NW-SE strik-ing linear structure 400 km long and up to 25 km wide, is the largest ophiolite association in Central Mongolia and possibly in all of Central Asia. The Bayankhongor cop-per mineralization was investigated by us in connection with detailed research of the ophiolite complexes in 1997-2011. With regard to their origin the ore formations belong to genetic type of gold-bearing massive sulphide deposit with magmatic seat of the island arc.     

南阿尔金茫崖地区花岗岩类锆石SHRIMPU-Pb定年、Lu-Hf同位素特征及岩石成因

南阿尔金茫崖地区早古生代花岗岩锆石SHRIMP U-Pb定年结果表明,阿克提山花岗岩为264±1Ma,柴水沟花岗岩分别为404±5Ma、406±4Ma,其中的辉绿岩为454±4Ma,常春沟花岗岩分别为411±5Ma、406±3Ma,茫崖镇北石英闪长岩为466±5Ma,阿卡龙山花岗岩为469±6Ma。锆石Lu-Hf同位素分析表明,εHf(t)值大多数为正值,少数继承性锆石为负值,反映了它们的源岩以新生地壳为主,同时,也混有少量的古大陆壳的成分。结合区域地质特征和各岩体的岩石地球化学特征,将南阿尔金茫崖地区早古生代花岗质岩浆活动划分为3期,第一期(465~469Ma)岩石组合为石英闪长岩+花岗闪长岩+花岗岩,具有岛弧火成岩的地球化学属性,其形成可能与洋壳的俯冲作用有关;第二期(404~411Ma)岩石组合为花岗闪长岩+二长花岗岩+正长花岗岩,具有A型花岗岩的地球化学特征,可能与板块碰撞后造山带块体均衡调整有关,第三期(264Ma)岩石组合为石英闪长岩+二长花岗岩+正长花岗岩,也具有I型花岗岩的特征,可能与阿尔金断裂的活动有关。     

http://www.sciencedirect.com/science/article/pii/S1674987114000887

The increasing number of fossil pterosaur eggs sheds light on nesting environments and breeding be- haviors of these extinct flying reptiles. Here we report the first partial three-dimensional egg of the pterosaur, Pteroduustro guinazui, from central Argentina. The specimen was discovered from the same Albian deposits as the exceptional R guinazui embryo described in 2004. Microscopic characterizations indicate a pristine preservation of the 50 Bm thick calcium carbonate, which differs significantly from the soft shell of Chinese pterosaur eggs. Estimate of the eggshell conductance implies that the nest had a minimum moisture content of 75%. This moisture estimate, combined with geological and taphonomical data, suggests that P. guinazui may have adopted a nesting strategy similar to those of grebes and flamingos rather than being buried on land, as previously hypothesized. Moreover, our results demon- strate that the nesting paleoenvironment of this pterosaur species was closely linked to a mesohaline lacustrine ecosystem in a basin governed by regional tectonic subsidence, a setting characteristic for the feeding and reproduction of modern flamingos.