秦巴地区主要地质—构造特征梗概

根据活动论和时空观,从8个方面总结了秦巴地区主要地质-构造特征。介绍了3大综合地层区的概貌,划分太古宇至元古代的地层类型及形成环境。从沉积盆地性质、基底构造格局等方面分析,指出中秦岭构造亚带为南、北板块拚接带的特定构造单元。根据宏观地质及地球化学特征,将本区火山岩的形成归纳为8种构造环境。概括了中酸性及碱性、偏碱性侵入岩类的时空分布和地球化学成分及成因类型等特点。从复杂的断裂系统、多期的叠加变形、多期构造-热事件和地壳极度缩短四方面,说明秦岭-大别山构造带是巨形强应变带。概述了秦巴构造演化8个阶段的主要点及基本构造格局。     

墨西哥ZacatecasFresnillo地区SantoNino脉的银硫盐

黑西哥ＦｒｅｓｎｉｌｌｏＡｇ－Ｐｂ－Ｚｎ地区的ＳａｎｔｏＮｉｎｏ脉中，银含在螺状硫银矿及三个含银矿盐固溶体系列的矿物中，这些硫盐矿物是：浓红银矿、淡红银矿、硫锑铜银矿、硒硫铜银矿、黝铜矿及脆银矿。     

内蒙古中元古界的褶叠层构造

在地壳较深构造层次、岩层间存在的明显韧性差以及大规模韧性水平分层剪切作用是形成褶叠层构造的先决条件。因此，褶叠层构造不仅仅在伸展构造体制中形成，只要条件具备，在挤压构造体制中也可形成。本文以渣尔泰群的褶叠层为例，论述在挤压构造体制中由于韧性水平分层剪切作用形成的褶叠层构造的展布规律、形态特征和在构造地质学中的意义。     

自然地带性的理论分析

假设地球以海平面为基准,完全摒弃起伏,亦不考虑陆地海洋两大物质体系的基本差别,那么可以想象得出,我们所居住的这个行星必将呈现为均匀、光滑、连续的几何球体.这样,由于其形状和运动的特性,以及它在宇宙中的位置,太阳辐射于地表上的能量,沿纬度的空间分布将显示出近乎完美的数学规律.这当然是一个极大简化了的理想模式.然而正是它构成了地表自然地带规律的雏形,并成为进一步分析的基础和出发点.     

全国天气雷达数据处理系统

根据《全国天气雷达终端更新》和《全国天气雷达定标》项目的技术规定,研制了一套完整的雷达业务数据处理系统,实现了全国布网天气雷达数据格式统一、产品生成、产品分发和图像回显的全自动化业务,提高了我国天气雷达网的业务质量、以及数据处理和产品应用水平,收效显著。在研发过程中,充分考虑了业务条件、实际要求和探测技术的发展,系统功能丰富,算法先进,接口开放,设计精美,投入业务两年来系统运行稳定。该系统放弃了传统对话框和工具栏的设计方式,创新设计了操作面板控制。文中的研发思路,设计方法,系统特点对我国业务软件的研制具有很好的借鉴作用。     

Preliminary evidence for human fecal contamination in corals of the Florida Keys,USA

Corals and reef environments are under increased stress from anthropogenic activities, particularly those in the vicinity of heavily populated areas such as the Florida Keys. The potential adverse impacts of wastewater can affect both the environment and human health; however, because of the high decay rate of bacterial indicators in coral reef waters it has been difficult to document the presence of microbial contaminants and to assign risks in these environments. Here we show initial evidence that microorganisms associated with human feces are concentrated along the surface of coral heads relative to the overlying water column in the Florida Keys. Bacterial indicators (fecal coliform bacteria, enterococci or Clostridium perfringens) were detected in 66.7% of the coral surface microlayer (CSM) samples at levels between five and 1000 CFU/100 ml, but were found infrequently and at low numbers in the overlying water column ( < or = 2.5 CFU/100 ml). Similarly, enterovirus nucleic acid sequences, an indicator of human-specific waste, were detected in 93.3% of the CSM samples and only once in the water column by cell culture. Results show that coral mucus may accumulate enteric microorganisms in reef environments, and may indicate a risk to public and environmental health despite low indicator levels in the surrounding water.     

First Results from Viper: Detection of Small-scale Anisotropy at 40 GHz

Using all available major samples of Seyfert galaxies and their corresponding closely matched control samples of nonactive galaxies, we find that the bar ellipticities (or axial ratios) in Seyfert galaxies are systematically different from those in nonactive galaxies. Overall, there is a deficiency of bars with large ellipticities (i.e., "thin" or "strong" bars) in Seyfert galaxies compared to nonactive galaxies. Accompanied with a large dispersion due to small number statistics, this effect is strictly speaking at the 2 sigma level. To obtain this result, the active galaxy samples of near-infrared surface photometry were matched to those of normal galaxies in type, host galaxy ellipticity, absolute magnitude, and, to some extent, redshift. We discuss possible theoretical explanations of this phenomenon within the framework of galactic evolution, and, in particular, of radial gas redistribution in barred galaxies. Our conclusions provide further evidence that Seyfert hosts differ systematically from their nonactive counterparts on scales of a few kiloparsecs.     

西藏日喀则地区德村-昂仁蛇绿岩内基性岩的元素与Sr-Nd-Pb同位素地球化学及其揭示的特提斯地幔域特征

系统研究了西藏雅鲁藏布江蛇绿岩带中部日喀则地区德村、吉丁和昂仁蛇绿岩中基性岩石的元素与 Sr-Nd-Pb 同位素地球化学特征。这些基性岩石,包括玄武岩、辉长岩和辉绿岩,属于低钾拉斑玄武岩系列,球粒陨石标准化稀土元素分配模式为轻稀土元素亏损的 N-MORB 型,(La/Yh)_N=0.31～0.65(除样品 DC993为1.17)。在原始地幔标准化微量元素图上,亏损高度不相容元素,与 N-MORB 配分模式一致。相对于 Th,无 Nb、Ta的亏损,显示样品不是产于 SSZ 环境。经构造环境图解判别,样品落入了 N-MORB 区域内;这些元素成分特征表明样品具有洋中脊环境或成熟的弧后盆地环境属性。Sr、Nd 和 Pb同位素组成特征表明特提斯地幔源区以 DM(亏损地幔)为主,同时存在少量 EMⅡ(富集地幔类型Ⅱ)、Sr,Nd 和 Pb 同位素组成特征还表明特提斯地幔域具有印度洋 MORB 型的 Sr-Nd-Pb 同位素组成特征。本文的结果进一步支持 Zhang et al.(2005)的研究结果,现今印度洋不仅在地理位置上占据了曾经是特提斯洋的大部分,而且它的地幔域还继承了曾经特提斯的地幔域的地球化学特征。     

大气本底基准观象台雷电防护系统工程的改造

大气本底基准观象台位于青海省海南州共和县瓦里关山,这里土壤电阻率高、雷电防护难度大,针对这些问题,在防雷设计与施工过程中采取了有效措施,工程完工后实测接地电阻值基本达到设计要求,现把设计与施工方法做简要介绍,供大家参考。