内蒙古四子王旗头号岩体锆石U-Pb同位素年代、岩石成因及构造意义

头号岩体位于华北板块北缘,西拉木伦河缝合带以南,侵位于新太古代变质花岗岩中,被晚侏罗世钾长花岗岩所侵入。通过LA-ICP–MS锆石U-Pb测年获得了(236.2±9.6)Ma(MSWD=3.6)的206Pb/238U加权平均年龄,应代表其侵位年龄。岩石地球化学分析结果显示,ω(SiO2)为73.09%⁷6.96%,ω(Na2O+K2O)为8.14%76.96%,ω(Na2O+K2O)为8.14%⁸.95%,A/CNK为1.03%8.95%,A/CNK为1.03%¹.13,标准矿物计算中各样品均出现刚玉(C),σ值为1.951.13,标准矿物计算中各样品均出现刚玉(C),σ值为1.95².54,为过铝质岩石、高钾钙碱性岩石系列。稀土元素蛛网图中,轻重稀土元素分馏较强,Eu为明显的负异常,大离子亲石元素(LILE)富集,高场强元素亏损(HFSE),Zr/Hf比值偏离较大,为S型花岗岩,并且岩浆作用后期可能与高温含水流体发生了相互作用。头号岩体形成于造山晚期向造山期后转变的构造体制下。结合前人区域研究资料,认为华北板块与西伯利亚板块已沿西拉木伦河缝合带闭合。     

Movement process analysis of the high-speed long-runout Shuicheng landslide over 3-D complex terrain using a depth-averaged numerical model

Landslides - Flow-like landslide is one of the most catastrophic types of natural hazards due to its high velocity and long travel distance. In 2019, a large catastrophic landslide was triggered by...     

概率赋范空间的有界性(英文)

研究了概率赋范空间中D-有界集被零向量邻域吸收的性质。同时对各种有界性的关系也进行了研究。     

天然气水合物勘查声学深拖系统研发方案

随着海底天然气水合物勘查工作的深入发展,近海底探测技术的应用越来越多,声学深拖技术的应用便是其中之一。简要介绍了目前深海探测中使用的多种弱正浮力型及重力型声学深拖系统,提出了用于天然气水合物勘查的重力型声学深拖系统的自主研发思路,论述了研发工作涉及到的若干关键技术。     

玛曲MS4.4地震震源机制解及其构造意义探讨

2021年5月22日青海省玛多县发生M_S7.4地震,数小时后在距离震中两百多公里的甘肃玛曲县发生了M_S4.4地震。利用甘肃、青海和四川区域测震台网记录的三分向宽频带数字波形资料,反演甘肃玛曲M_S4.4地震的震源机制解,结果显示此次地震活动面走向、倾角和滑动角分别为105.6°、74.1°和-38.7°。参考玛多M_S7.4地震的震源机制解,发现两次地震震源机制解具有较好的一致性,均呈现明显的左旋走滑特征。静态库伦破裂应力改变量分布计算结果表明,玛曲M_S4.4地震震中位置单位面积(m~2)受到来自玛多地震震中方向的拉应力约为0.02 MPa。综合两次地震的震中距、发震时刻和断层分布等情况,初步判断甘肃玛曲M_S4.4地震应为青海玛多M_S7.4强震的一次触发地震。     

普通克里格法在矿产储量计算中的应用

普通克里格法能充分利用样品信息，有效地提高块段平均品位及矿产储量精度。以刁泉银铜矿为实例，介绍了该方法的理论和方法应用以及储量计算流程图。     

Mapping soil organic carbon stocks of northeastern China using expert knowledge and GIS-based methods

The main aim of this paper was to calculate soil organic carbon stock (SOCS) with consideration of the pedogenetic horizons using expert knowledge and GIS-based methods in northeastern China. A novel prediction process was presented and was referred to as model-then-calculate with respect to the variable thicknesses of soil horizons (MCV). The model-then-calculate with fixed-thickness (MCF), soil profile statistics (SPS), pedological professional knowledge-based (PKB) and vegetation type-based (Veg) methods were carried out for comparison. With respect to the similar pedological information, nine common layers from topsoil to bedrock were grouped in the MCV. Validation results suggested that the MCV method generated better performance than the other methods considered. For the comparison of polygon based approaches, the Veg method generated better accuracy than both SPS and PKB, as limited soil data were incorporated. Additional prediction of the pedogenetic horizons within MCV benefitted the regional SOCS estimation and provided information for future soil classification and understanding of soil functions. The intermediate product, that is, horizon thickness maps were fluctuant enough and reflected many details in space. The linear mixed model indicated that mean annual air temperature (MAAT) was the most important predictor for the SOCS simulation. The minimal residual of the linear mixed models was achieved in the vegetation type-based model, whereas the maximal residual was fitted in the soil type-based model. About 95% of SOCS could be found in Argosols, Cambosols and Isohumosols. The largest SOCS was found in the croplands with vegetation of Triticum aestivum L., Sorghum bicolor (L.) Moench, Glycine max (L.) Merr., Zea mays L. and Setaria italica (L.) P. Beauv.     

矢量地形图拓扑等问题的研究与实践

对矢量地图生产过程中常见的图形拓扑、数据冗余问题进行分析和研究；在此基础上结合生产实践，提出了相应的解决办法。研制了基于AutoCAD2000平台的相关程序。     

清代地理学家魏源及其《海国图志》──纪念魏源诞生200周年

本文阐述我国清代中期思想家、地理学家魏源的思想及共《海国图志》的特点及历史意义。     

Deformation Mechanism and Stability of a Rocky Slope

A high slope is located on the side of the spillway at a hydropower station in Southwest China, which has some weak inter-layers inclining outwards. Parts of the slope show heavy weathering and unloading. There appeared deformation and tensile crack either on the surface or on the afteredge of the slope during excavation, and under a platform （elev. 488 m）, two levels of slopes collapsed on the downriver side. Based on the investigation in situ and the analysis of the geological structure, the conceptual model of deformation and failure mechanism was erected for this slope. Furthermore, the deformation characteristics were studied with FLAC^3D numerical simulation. Comprehensive analysis shows that the whole deformation of the slope is unloading rebound in certain depth scope and the whole body does not slide along any weak interlayer. In addition, two parts with prominent local deformation in the shallow layer of the slope show the models of ＂creep sfiding-tensile cracking＂ and ＂slidlng-tensile cracking＂, respectively. Based on the above analysis, the corresponding project of support and reinforcement is proposed to make the slope more stable.