Geostatistical regionalization of glacial aquitard thickness in northwestern Germany, based on fuzzy kriging

In many instances hydrogeological parameters obtained by conventional methods for selected localities within an aquifer or an aquitard are not sufficient for adequate regionalization at the scale of the entire layer. Here, we demonstrate an application of the fuzzy kriging method in regionalization of hydrogeological data, in which the set of conventional, crisp values is supplemented by imprecise information subjectively estimated by an expert. It is believed that such an approach eventually may reflect the real-world conditions more closely than a traditional crisp-value approach, because the former does not impose exactness artificially on phenomena which are diffuse by their nature. Spatial interpolation was done for the thickness of one of the major aquitards (till and glaciolacustrine clay) in northwestern Germany. The dataset consists of 329 crisp values from boreholes supplemented by 172 imprecise values defined as fuzzy numbers. It is demonstrated that the reliability of regionalization was higher, compared to regionalization performed with the crisp dataset only. Fuzzy kriging was performed with FUZZEKS (Fuzzy Evaluation and Kriging System) developed at the Ecosystem Research Center at the University of Kiel.     

A note on thermomechanical anisotropy of clays

Deep clays exhibit a pronounced strain anisotropy both during mechanical loading as well as during heating and cooling at constant stress in drained isotropic conditions. During mechanical loading vertical strain is larger than the horizontal one. During heating the vertical strain is larger than the horizontal one within the elastic range; the opposite is observed in the elasto-plastic range. The above described response can be interpreted adopting a consistent rotational, kinematic hardening thermo-elasto-plastic constitutive law.     

Overview of in-situ thermomechanical experiments in clay: Concept, results and interpretation

The HADES project (High Activity Disposal Experimental Site) aims at demonstrating the technical feasibility and the long-term safety of geological disposal of reprocessed HLW (High-Level Wastes) radioactive wastes. This disposal could be realised in the Tertiary Boom clay formation below the Mol/Dessel nuclear site. Previous studies in the 80's on the geomechanical behaviour of Boom clay, at host rock temperature (15°C), have demonstrated the mining capabilities of this clay. European partners have collaborated to increase the number of in-situ tests to be developed and operated from the Underground Research Facility (URF). Integrated large-scale experiments have been developed during the last four years, within the framework of the Commission of the European Communities (CEC) research contracts, in order to gain more insight into the thermal influence of heat-emiting wastes on the clay behaviour in the near field.

This paper summarizes the knowledge gained from the in-situ hydro-thermo-mechanical experiments realised from the URF. The objectives and main issues of the tests are described. Information regarding selection of parameters and representativeness of their measurements is discussed. Despite their different aims and designs, three hydro-thermo-mechanical experiments are compared in order to emphasize similarities in the general behaviour of the clay massif submitted to a thermal load. It is observed that its behaviour is qualitatively similar to the reaction upon a constant total stress increase. With the information now available, it is not obvious to draw conclusions with respect to the irreversibility of some phenomena.

Simple in-house analytical codes are able to simulate with a good accuracy the hydro-thermo-mechanical behaviour of clay. Nevertheless, these codes are not sufficient to describe the complexity of the phenomena that are involved in hydro-thermo-mechanical processes as pointed out by field data. In order to validate more complex models, the possibilities to improve the representativeness of the measurements are investigated.     

青藏高原东北地区现代降水中δD与δ^18O的关系研究

根据对取自青藏高原东北地区部分降水样中氢氧稳定同位素比率的分析，得到沱沱河站的大气水线（ＭＷＬ）为：δＤ＝８．２５δ＾１８Ｏ＋９．２２‰，与全球平均ＭＷＬ的差别较小；德令哈、西宁站的ＭＷＬ分别为：δＤ＝５．８６δ＾１８Ｏ－２７．２８‰和δＤ＝６．９６δ＾１８Ｏ－３０．１９‰，均与全球平均ＭＷＬ差别较大。这主要归因于水汽源地的非平衡蒸发和凝结物在非饱和大气中降落时的非平衡蒸发。上述地区的过量氘Ｅｘｄ     

黑龙江省东部跃进山群中绿片岩的地球化学特征及地质意义

跃进山群出露位于佳木斯地块和那丹哈达地体之间，是完达山造山带的组成部分。它由大陆斜坡相沉积物、大洋中脊型玄武岩和洋岛型玄武岩组成，其中有镁铁－超镁铁质岩块体。它不是一个地层单位，而是与活动大陆边缘板块俯冲作用有关的蛇绿混杂岩     

内蒙古科尔康油田沙海组储集层的岩石学特征

根据碎屑岩铸体薄片和扫描电镜观察分析资料，研究了科尔康油田沙海组储集层的岩石学特征。科尔康油田沙海组储集层的岩石类型主要为岩屑砂岩和岩屑砂砾岩。碎屑岩的岩性特征对沙海组储集层的成岩作用具有显著的影响作用。     

Mineral inclusions in diamonds from the Sputnik kimberlite pipe, Yakutia

The Sputnik kimberlite pipe is a small “satellite” of the larger Mir pipe in central Yakutia (Sakha), Russia. Study of 38 large diamonds (0.7-4.9 carats) showed that nine contain inclusions of the eclogitic paragenesis, while the remainder contain inclusions of the peridotitic paragenesis, or of uncertain paragenesis. The peridotitic inclusion suite comprises olivine, enstatite, Cr-diopside, chromite, Cr-pyrope garnet (both lherzolitic and harzburgitic), ilmenite, Ni-rich sulfide and a Ti-Cr-Fe-Mg-Sr-K phase of the lindsleyite-mathiasite (LIMA) series. The eclogitic inclusion suite comprises omphacite, garnet, Ni-poor sulfide, phlogopite and rutile. Peridotitic ilmenite inclusions have high Mg, Cr and Ni contents and high Nb/Zr ratios; they may be related to metasomatic ilmenites known from peridotite xenoliths in kimberlite. Eclogitic phlogopite is intergrown with omphacite, coexists with garnet, and has an unusually high TiO₂ content. Comparison with inclusions in diamonds from Mir shows general similarities, but differences in details of trace-element patterns. Large compositional variations among inclusions of one phase (olivine, garnet, chromite) within single diamonds indicate that the chemical environment of diamond crystallisation changed rapidly relative to diamond growth rates in many cases. P-T conditions of formation were calculated from multiphase inclusions and from trace element geothermobarometry of single inclusions. The geotherm at the time of diamond formation was near a 35 mW/m² conductive model; that is indistinguishable from the Paleozoic geotherm derived by studies of xenoliths and concentrate minerals from Mir. A range of Ni temperatures between garnet inclusions in single diamonds from both Mir and Sputnik suggests that many of the diamonds grew during thermal events affecting a relatively narrow depth range of the lithosphere, within the diamond stability field. The minor differences between inclusions in Mir and Sputnik may reflect lateral heterogeneity in the upper mantle.     

赣东北地区前震旦系地层金的原生富集趋势探讨

在分析变质岩的含金性及地球化学性质的基础上，认为与金成矿有关的主要元素均源自前震旦系。指出了金的原生富集趋势和存在的矿源层。为在该区寻找金矿指出了方向     

丰城洛市地区推,滑覆构造特征及其成因探讨

介绍了洛市地区推、滑覆构造特征、运动学标志及其形成时期、成因模式。