粗粒料湿化变形后的抗剪强度分析

采用大型三轴仪,对双江口坝壳粗粒料进行了不同围压、不同应力水平的湿化试验研究,并对湿化变形后的抗剪强度进行了分析。各个湿化应力水平下的抗剪强度指标近似相等,其c值在风干态和饱和态之间,更接近于饱和态值,而? 值也有相同规律,其值较固结排气剪略有降低,更接近于饱和态的摩擦角。     

水利工程建设对地下水影响的数值模拟分析

工程开挖及建成后对含水层结构的改造,无疑会对开挖区周围地下水造成影响。利用数值模拟方法分析预测某水利工程尾水渠开挖及建成后周围地下水水位的变化。预测结果,大开挖后周边地下水位将快速降低,且不同地段水位降幅不同,右岸阶地内水位降低约0.26~7.26 m,工程建成后,阶地内水位将逐渐恢复,但相比施工前水位仍降低0.09~0.38 m。分析水文地质结构,合理概化,建立数值模型,对于分析工程开挖对地下水的影响,是种有效方法。     

开发区不同行业工业用地集约利用水平评价——以辽宁省北票开发区为例

以北票开发区为研究对象,通过对不同工业行业进行划分,建立不同行业工业用地土地集约利用水平评价指标体系,应用多因素综合评价模型对开发区内不同行业工业用地集约利用水平进行了测算,揭示其集约利用水平及其差异性,研究结果表明：北票开发区整体工业用地集约利用水平较高,其中纺织业、服装及其他纤维制品制造业和化学原料及化学制品制造业用地集约水平最高,而饮料制造业用地集约利用水平最低。     

基于数据中心的国土资源信息系统基础平台的构建及技术问题

国土资源信息化建设是我国今后几年的工作重点.国土资源信息化的基础是国土信息的集成.在国土信息集成的工作中, 主要存在3个方面的问题: (1) 不同GIS间的数据无法共享; (2) 不同种类的国土数据无法集成; (3) 不同行政级别单位间数据无法共享.不同GIS的数据共享可以通过在GIS的ODBC层和数据库之间加一层GIS格式转换层来解决; 将不同种类的国土数据划分成不同的图层, 以空间控制点方式对这些图层进行叠合, 以使它们在空间关系上成为一个比较一致的统一系统; 借鉴数据仓库的管理模式, 不同的行政单位对应于不同的比例尺的数据, 高级别单位数据的综合度高, 存放的数据少, 低级别单位数据的细节性强, 存放的数据多, 整体上呈现出金字塔结构, 金字塔中不同层次的数据通过空间控制点进行传送.国土信息集成的目的是构筑一个国土信息系统的基础平台.国土资源信息系统基础平台是一个基于数据中心的、能统一管理信息的、支持现有流行GIS访问的、能与上下级数据中心无缝互连的国土资源基础设施系统.它处于整个国土信息系统的底层, 目的是向上层的信息系统提供一个能满足各种格式的数据需求的、而与具体的信息系统无关的独立的数据平台.      

The Stability of Upper Bound Analysis of Soft Rock Tunnel Faces Under Different Underground Water Levels

The effect of underground water levels on the stability of soft rock tunnel faces was analyzed in this paper. The underground water levels was divided into three cases, and the Hoek–Brown failure criterion was introduced into the kinematic approach by "tangent method", then three kinds of stability analysis model of tunnel faces under different underground water levels was constructed. Based on the principle of virtual power, the expressions of supporting force on the tunnel faces of soft rock under different underground water levels were derived. Moreover, the optimal upper limit solution of the supporting force on tunnel faces was obtained by using the sequential quadratic programming algorithm with Matlab software. After that, the effect of underground water levels on the supporting force of tunnel faces was analyzed, and the damage range of tunnel faces under different underground water levels was given. This paper provides some reference value for setting parameters of shield tunneling in water-rich section.

     

尾水隧洞衬砌混凝土裂缝预防及治理

水工隧道混凝土衬砌均存在不同程度的裂缝,本文介绍了尾水隧洞衬砌混凝土裂缝预防和不同类型裂缝的处理办法。     

化探数据系统分析的应用效果

化探数据系统分析可以提取与不同成矿单元度水平相应的信息，其中包括矿床主控因素的信息。本文所引的两个例分别表现了层控矿床和岩控矿床地球化学场的不同特点，获得了地球化学异常图上没有的信息。此外，同一元素不同尺度滑动平均异常的套合及同一尺度的不同元素异常的套合都是评价含矿性的重要信息。     

漫滩河流防洪水位研究

通过物理模型试验对松花江某平原漫滩河段的沿堤防洪水位进行了研究,对主槽和滩地阻力采用了不同的模拟方法,在达到模型相似的基础上,试验量测了水流边界沿低水位随流量的变化关系。研究表明,因河段内阻力因素复杂,边界沿堤水位与同断面主槽水位差别最大可达0.3m。     

Dynamic Response of Sandy Slope Under Coupling of Earthquake and Groundwater

Based on dynamic elastic–plastic time history analysis method, dynamic responses of sandy slope in different groundwater levels are studied under near field earthquakes and far field earthquakes. The results show that the accelerations of the slope decrease with the increasing of groundwater levels, which demonstrates that the existence of groundwater damps vibration. The accelerations have different laws along the height of the slope under far field and near field earthquakes, however, the maximum values all appear at the top of the slope. The maximum horizontal displacement of the slope increases with the increasing of groundwater levels. The influence of far field earthquake on the deformation of slope toe is greater, while the influence of near field earthquake on the deformation of the slope top is greater. Thus, the top and the toe of the slope should be protected as the key position under earthquakes. The influence of high groundwater level on stability of the slope is more serious, and the safety factor calculated by pseudo-static method in slope seismic code will be lower for the slope in the high groundwater level.     

Phosphorus distribution and retention in lacustrine wetland sediment cores of Lake Changshou in the Three Gorges Reservoir area

Lake Changshou is a eutrophic reservoir of the Longxi River in the Three Gorges Reservoir area. In this study, we sampled the sediment of the lacustrine wetland to determine phosphorous (P) fractions, their distribution, and retention along the water level, with the overall aim to evaluate biogeochemical P migration. Total phosphorus (TP) concentrations in the water-level zone varied from 106.60 to 1178.86 mg/kg, with highest levels in the shallow-water area. With increasing sediment depth, TP levels decreased. The different wetland zones (land area, area with fluctuating water levels, shallow-water area, and deep-water area) were dominated by different P fractions. Based on our results, the hot spot of P accumulation in the littoral zone is the shallow-water area, possibly because of the significant hydrological changes.     

Features of the Structures and Evolution of the Lower Part of the Continental Crust of the Yakutian Diamondiferous Province within the Upper Muna Kimberlite Field

Doklady Earth Sciences - Study of xenoliths of crustal rocks from the Novinka kimberlite pipe (Upper Muna kimberlite field) showed that the crust at different levels is composed of pyroxene and...     

基于RS与GPS的汶川地震路基路面震害损毁调查——以都汶公路为例

文章以都汶公路为例,利用遥感解译技术快速获取地震诱发山地灾害类型及其对公路造成的严重损害类型,利用GPS对公路损毁灾害点准确定位,获得路基路面直接震害类型信息,同时对山地灾害遥感判识结果进行检验。通过分析认为公路沿线岩体岩性以及风化破碎程度的不同,对公路产生的损毁程度不相同;路基破坏程度与距离震中和断裂带的远近有密切关系;路基下方护坡的破坏与所处边坡的坡度有关;崩塌滑坡产生大量松散固体物质,雨季到来之后,极易暴发大规模泥石流,需要注意并防范泥石流对行车安全和道路交通的影响。     

基于历史地震人员死亡数据的抗致死性水平分级

基于历史地震中各个烈度的人员死亡率数据,通过拟合分析,发现这些震例从分烈度人员死亡率的角度具有较明显的差别和分组现象,同组内不同震例死亡率的变化率小于50%。分组特征代表了不同组的震例在各个烈度下均有不同的人员死亡率区间,这种分组特点和组间人员死亡率的不同所指示的是这些震例发生区域的抗致死性水平的不同。研究表明：位于同一省份的不同震例的人员死亡率可能出现较大差别,说明即使同省份的不同区域也可能具有不同的抗致死性水平;而相距甚远的不同省份的震例却可能具有大致相同的死亡率,说明一些并不相邻的不同区域也可能具有大致相同的抗致死性水平。本文基于分烈度死亡率拟合直线斜率所代表的死亡率的分组特征,将全国各地的抗致死性水平分为11级,每一级的抗致死性水平都代表了一组分烈度人员死亡率区间。抗致死性水平等级越高,对应的各烈度人员死亡率越低,抗致死性水平与人员死亡率呈现逆相关关系。     

Water level variations in fractured,semi-confined aquifers of Anantapur district,Southern India

The study on water level conditions of fractured aquifer system in northeastern part of Anantapur district is of immense importance as the area is covered by varied geological formations and has different irrigation patterns. The monthly groundwater level data of 154 observation wells for five year period (2001–06) is analyzed to decipher the behavior of water levels in different seasons and geo-environments. The hydrographs of the average water level data of each Mandal (group of villages) indicate steady declining trend ranging from 0.50 to 2.91m/yr. Yellanuru Mandal has both the shallowest and the deepest water levels among eight Mandals, highly undulating terrain could be one of the reasons for this contrasting condition. The pre-monsoon water levels show decline of 8.22 m in one year from May 2002 to 2003. A negative seasonal fluctuation of ?1.49m has occurred in the year 2002 during which the area received 32% less than normal rainfall. The mean water levels are deeper by 42% in areas covered by sedimentary formations than those of granite terrain. Raise in water levels is significant where monthly rainfall is more than 200 mm. Due to erratic rainfall in space and time, deeper water levels are noticed even in post-monsoon period and shallow in February month at some locations. The water levels in command areas are deep and exhibit falling trend as the area forms the tail end part of the Tunga Bhadra High Level Canal. The deeper water level conditions and its declining feature is directly related to groundwater development in the form of increased agriculture activity, reduced area under rain-fed crops, high horticulture development. Arid climatic conditions, low precipitation and continuous exploitation of groundwater resources could be other factors contributing for steady decline in water levels in the area. The wide variations in groundwater levels could be due to uneven topography, heterogeneous and anisotropic conditions of granites and poor porosity — permeability of shales, lack of vegetation, and increased groundwater extraction.     

Geochemical evidence for consecutive accretion of oceanic fragments: The example of the Samarka Terrane,Sikhote-Alin

The data of geochemical study of Late Triassic cherts from tectonic–sedimentary complexes from different structural levels of the Samarka Terrane are reported. It is shown that the concentration and character of distribution of the major petrogenic oxides and minor and rare-earth elements in cherts of the upper and lower structural levels differ significantly, which results from differences in the facies environments of chert deposition. All the geochemical characteristics of cherts show that their deposition proceeded in the pelagic area of sedimentation, but in different parts. The Katen Complex composing the lower structural level is the most distant from the continental margin. The closest is the Amba-Matay Complex composing the upper structural level. Based on the geochemical and biostratigraphic data and the age of accretion of paleooceanic fragments, the length of the subducted oceanic plate (>6000 km) is calculated.     

大气-生物圈相互作用的层次性——兼对模式研究的述评

从大气和生物圈构成的层次性出发,提出了大气—生物圈相互作用的三个层次,在此框架基础上,分析了不同研究(模式)的特点,并强调指出建立大气—植物圈(植被)层次上的相互作用模式是使相互作用研究真正建立在动态的、完整的基础之上的关键。     

应用测井资料的"三瞬"属性进行地层划分及对比研究

地层划分及对比是油气田勘探开发一项重要且存在难题的工作,提出应用 Hilbert-Huang变换方法提取常规测井资料(自然伽马、声波时差等)的"三瞬"属性特征进行地层划分及对比,即"瞬时频率"、"瞬时振幅"、"瞬时相位"3个属性,揭示了测井数据各深度处的频率特性,可以清晰反映出频率变化的结构特征.依据不同属性的振荡异常刻度层序边界,不同频率成分的属性振荡周期变化特征刻度不同规模的层序旋回周期特征,进而利用"三瞬"属性信息进行地层对比,刻画地层内部特征.利用这些属性异常可以清晰地找到对应地层序列中不同级别的界面,进而实现对各级层序划分,在各级层序格架控制下,进行各级地层等时对比.提取测井资料的三瞬属性为高分辨率层序地层研究提供了一种新的方法思路,为推动高分辨率层序地层学的发展具有重要意义.     

The research on division and correlation of stratigraphic sequence based on the “three instantaneous” attribute features of logging data

The stratigraphic division and correlation has important guiding significance to oil and gas field. This paper presents the application of Hilbert-Huang Transform to extract the “three instantaneous” attribute features of logging data (GR,AC) to perform the division and correlation of stratigraphic sequence, that is, the three properties of "instantaneous frequency", "instantaneous amplitude", "instantaneous phase" are extracted from logging data, which revealed the frequency characteristics of each depth of logging data and clearly reflected the structural characteristics of the frequency change. According to the oscillation anomalies of different attributes, we scale sequence boundaries, and use the variation characteristics of oscillation period of different frequency components attributes to scale the periodic characteristics of different scale sequence cycle, then use the “three instantaneous” attribute information for stratigraphic correlation, and for describing the internal features of formation. These attributes anomalies can be used to clearly find the different class interface of stratigraphic sequence, to achieve the sequence division at all levels, and under the control of sequence stratigraphic framework at all levels, we can do the isochronous stratigraphic correlation at all levels. The “three instantaneous” attribute extraction of logging data provides a new approach and idea for high resolution sequence stratigraphy analysis, and it has important significance for promoting the development of high-resolution sequence stratigraphy.     

The distribution of local bedrock material in some moraine forms form the inner part of northern Sweden

An inventory of bedrock material has been made from different levels in some moraine types situated in the areas around Storvindeln and Storavan. The results show that moraine forms which have a curved morphology transverse to the direction of ice flow, always have a high content of local bedrock material independent of till thickness. In many cases the local bedrock material is represented more in the upper levels of the moraine. Large transverse ridges with less curvature have a highly variable bedrock content. Drumlins may lack local bedrock material over a distance of many kilometres. The variable distribution of local bedrock material in different moraine types has been interpreted as a function of ice pressure, temperature, and movement during deglaciation.