Crustal reflection structure in the uplifting zone of Songliao Basin and disconnecting Moho interface

Songliao Basin is one of the most important bases for oil-gas resources of China. Therefore, the mecha-nism of petroleum occurrence and basin dynamics have been paid much attention to by geo-scientists all the time. With multi-phase tectonic movements en-dured by the basin, its tectonic pattern is very complex. Thereinto, three faults, that is, western Neijiang fault(NNE25), eastern Yilan-Yitong fault (NNE30) and Sunwu-Shuangliao fault, extend along south-north direction and cut Songliao…     

Flow dimension as an indicator of hydraulic behavior in site characterization of fractured rock

We examine the possibility of using the flow dimension identified from constant pressure injection tests as a tool for characterizing the hydraulic conditions of fractured media. The data comes from a low-conductivity crystalline rock site, from depths of up to 450 m, and is obtained with 2 m and 10 m measurement scales. In the analysis, the general solution for n-dimensional flow by Barker (1988) is applied. The results show that the most prominent characteristics of the medium can be identified; that is, linear and sublinear flow dimensions as distinguished from dimensions higher than two. In many cases, however, there is significant difficulty in distinguishing the dimensions n = 2, 2.5, and 3 from each other. This is usually because of the experimental difficulties in achieving the ideal conditions required by the theory during the early part of the experiment. In such cases, a full flow curve is not available for the type-curve fitting. In the nonunique cases the higher dimensions typically correspond to higher, sometimes unrealistically high, values of specific storage and to the less reliable and less representative early part of the experiment. Therefore, most of the dimensions in categories n = 3 can be excluded, thus leaving the majority observations in the categories of n = 2 and n = 2-2.5. The dominance of dimension n = 2 is more pronounced for data related to fracture zones in comparison to that related to "average" rock, in particular in the 2 m scale data. The proportion of low (n < 1.5) flow dimensions is small, but for the 10 m scale data it is relatively higher at greater depths and corresponds to lower conductivities. For the smaller 2 m scale data, the low dimensions are not linked to greater depths or systematically smaller conductivities, giving preliminary indication of different flow dimension behavior for the two different scales.     

Polycyclic aromatic musk compounds in sewage treatment plant effluents of Canada and Sweden--first results

Polycyclic musk fragrances (PMF) are widely used fragrances for cosmetics and other personal and household care products. Quantitative data on PMF (HHCB-Galaxolide, AHTN-Tonalide, ATTI-Traseolide, AHMI-Phantolide, ADBI-Celestolide, and DPMI-Cashmeran) and the most prominent nitro musks (Musk Xylene-MX, and Musk Ketone-MK) in different wastewater treatment effluents in Canada and Sweden are presented to provide preliminary information on the variations within the emission pattern of these compounds. In all samples HHCB and AHTN were detected at concentrations of up to 1300 and 520 ngl(-1), respectively. ADBI, AHMI were also present, but close to the detection limit. The other PMF DPMI, ATTI, and more surprisingly musk ketone and musk xylene were not detected in any sample analysed. In comparison the samples from Canada were contaminated at a higher level than the Swedish samples, by a maximum factor of ca 10 for HHCB and AHTN.     

参考数据集的数据质量管理

地理信息团体习惯于使用现有的数据集,元数据(关于数据的数据)也随之日渐重要,数据质量正是元数据的一个重要方面。为广泛使用地理信息,出现了包括全球空间基础设施、欧洲的 INSPIRE以及国家空间数据基础设施(澳大利亚、美国)等项目。开放地理信息系统联盟 (OGC)已推出在不同应用程序间的数据转换方     

单站短期降水预报

这种方案有价值的特征之一是,一有所选站点的观测值,马上就可以作出预报。不象数值动力天气预报漠式那样需要3个多小时去收集和分析数据,把模式置于初始状态,然后才能作出预报。此外,象 MOS 一类可用的统计方法也需要首先完成数值天气预报模式。人们已经指出,马尔柯夫(MarKov)模式可以作为使用少量现有资料而迅速得到     

关于电磁模型简单表示方法的使用

由G. N. Polozhii提出的电磁模型简单表示法是解决由规则网格表示的自伴的有限差分边值问题的一种准分析方法。从其原理看,这种方法同一般有限差分法比较在计算时间方面有相当的节约,并且精度有所提高。为解决电磁模型中二维赫姆霍兹方程问题,我们已经用简单表示法作为新的混合方法的基础。这个混合方法的理论也将予以介绍。对二维问题的初步试算结果表明这种方法能节约大量计算时间和存贮单元。     

偏移垂直地震剖面的旅行时间反演——一种可行性研究

使用偏移垂直地震剖面(VSp)的旅行时间,应用迭代最小平方反演方法可以估算地下的二维倾角。利用合成数据进行试验表明,用直达波或一次反射的旅行时间,由这种反演技术能够估算一个钻井附近的倾角。这种反演方法实质上是一种“剥层”方法,即先估算浅层的倾角,然后估算深部的倾角。几个实例表明,当震源偏移距与层深度的比率很小时,一次反射是主要的波。旅行时间反演还需要精心算层速度和正确的校正静。如果不考虑这些困难和普遍存在的非单值性问题,旅行时间反演可以产生一个正确的地层模型,以用于实际数据的检验。     

对今后地质学的几点看法

该文介绍了苏联地质学的一些理论与实践,如研究成矿规律的地质层系学说,地磁法、电测法和地震勘探法等地球物理找矿方法,地球化学找矿方法以及实验矿物学、人工合成矿石等。     

A—型花岗岩的成因:实验的控制因素

关于具有特征化学成分的A-型花岗岩或非造山花岗岩的成因,人们已经提出了许多岩石成因的理论模式。对澳大利亚东南部A-型花岗岩伴生流纹岩和玄武岩双峰态组合的Watengums偏铝质花岗岩进行了实验研究,以便探讨其成因。Watergums岩浆浸入于地壳很浅的部位。且几乎处于全熔状态。因此在~-1kb时,晶-液相关系可以同岩相学上已确定的结晶顺序进行对比。资料表明,这种岩浆的最低温度为830℃,可能超过900℃推断熔体中水的含量为2.4—4.3％。这种岩浆的温度高,暗示在成因上与稍晚的I-型花岗岩是有区别的。岩石学、地球化学以及实验资料直接证明了A-型花岗岩是下部地壳中亏损熔体的I-型花岗岩源岩高温部分熔融形成,幔源岩浆(玄武岩)为产分熔融提供了热源。熔融作用很可能伴随缺少流体相而略富卤族元素的云母和闪石类矿物的分解。这些矿物是早期形成I—型岩浆后的熔融残余。由于A-型岩浆温度高、中等水分以及高F,特别当它分馏时显示出低粘度,这与A-型流纹岩、黑(?)岩流体的正常产出是一致的。相反,S-型和I-型火山岩通常为火山灰流的凝灰岩。