Developing a comprehensive evaluation method for Interconnected River System Network assessment: A case study in Tangxun Lake group     

Yang  Wei  Zhang  Liping  Zhang  Yanjun  Li  Zongli  Xiao  Yi  Xia  Jun 《地理学报(英文版)》2019,29(3):389-405

Journal of Geographical Sciences - The Interconnected River System Network (IRSN) plays a crucial role in water resource allocation, water ecological restoration and water quality improvement. It...  相似文献   

新疆绿洲城镇组群内部经济联系及空间差异测度研究          下载免费PDF全文

李雪梅 《干旱区地理》2019,42(1):180-186

绿洲城镇组群是新疆特殊区域形成的规模相对较小的单一中心空间自组织模式。运用城市中心性指数、城市经济联系模型和Theil系数对新疆八大绿洲城镇组群内部城镇中心性、经济联系及空间差异测度。结果显示：绿洲城镇组群内部的中心城市的中心性职能较强，周边城镇的中心性职能相对较弱，形成了单中心的空间自组织模式；绿洲城镇组群内部经济联系量和经济联系隶属度大小的排序一致，离中心城市的距离越近、经济发展水平越高，经济联系隶属度越高；近10 a年来绿洲城镇组群的整体空间差异一直在扩大，且呈现出继续扩大趋势。在此基础上，提出了建立区域合作协调机制、明确城镇组群发展方向、增强中心城市的辐射带动作用、实现产业合理分工以及构建制度保障体系促进绿洲城镇组群的协同发展。  相似文献   

淄博市西宝山耐火黏土矿地质特征及找矿方向     

孙聪聪 《山东国土资源》2020,36(3):20-25

西宝山耐火黏土矿为沉积型矿床,目前揭露1个耐火黏土矿矿层,赋存于石盒子群万山组底部“B”层黏土岩的下部,厚度较稳定,勘查开发潜力较大。通过对其地质特征、矿层特征、矿石结构构造及矿床成因分析,提出了找矿方向。认为该耐火黏土矿受沉积地层控制,呈层状分布,分布较稳定。依据该区地层产出情况,在青龙山断裂与禹王山断裂之间及两侧均具有良好的找矿前景,这为下一步找矿工作奠定了基础。  相似文献   

Effect of Shale Reservoir Characteristics on Shale Oil Movability in the Lower Third Member of the Shahejie Formation,Zhanhua Sag     

NING Chuanxiang  MA Zhongliang  JIANG Zhenxue  SU Siyuan  LI Tingwei  ZHENG Lunju  WANG Guozhen  LI Fengxun 《《地质学报》英文版》2020,94(2):352-363

To reveal the effect of shale reservoir characteristics on the movability of shale oil and its action mechanism in the lower third member of the Shahejie Formation(Es3l), samples with different features were selected and analyzed using N2 adsorption, high-pressure mercury injection capillary pressure(MICP), nuclear magnetic resonance(NMR), high-speed centrifugation, and displacement image techniques. The results show that shale pore structure characteristics control shale oil movability directly. Movable oil saturation has a positive relationship with pore volume for radius > 2 μm, as larger pores often have higher movable oil saturation, indicating that movable oil is present in relatively larger pores. The main reasons for this are as follows. The relatively smaller pores often have oil-wetting properties because of organic matter, which has an unfavorable effect on the flow of oil, while the relatively larger pores are often wetted by water, which is helpful to shale oil movability. The rich surface provided by the relatively smaller pores is beneficial to the adsorption of immovable oil. Meanwhile, the relatively larger pores create significant pore volume for movable oil. Moreover, the larger pores often have good pore connectivity. Pores and fractures are interconnected to form a complex fracture network, which provides a good permeability channel for shale oil flow. The smaller pores are mostly distributed separately;thus, they are not conducive to the flow of shale oil. The mineral composition and fabric macroscopically affect the movability of shale oil. Calcite plays an active role in shale oil movability by increasing the brittleness of shale and is more likely to form micro-cracks under the same stress background. Clay does not utilize shale oil flow because of its large specific surface area and its block effect. The bedding structure increases the large-scale storage space and improves the connectivity of pores at different scales, which is conducive to the movability of shale oil.  相似文献   

乌兰浩特地震台典型地震事件震相特征分析     

包宝小  贾宝金  刘芳  席文雅  杨志霞 《地震地磁观测与研究》2020,(1):33-39

选取乌兰浩特地震台记录到的典型天然地震事件及爆破事件,根据断裂带分布及波形记录特征,分析地震及爆破事件的震相特征.结果表明,研究区域近震波形Pn、Pg、Sn、Sg震相及Sm面波较清晰,Pg、Sg波走时差一般不大于23 s,与中国地震台网中心发布的MS震级间的偏差一般小于0.6级;远震P、S、pP、sP震相可较清晰识别,Pm、L面波记录较明显,P、S波走时差一般不小于25 s,震级偏差一般小于0.4级,且通过震相特征及实地考察发现,爆破多为霍林郭勒区域爆破事件.  相似文献   

地震作用下低层建筑砌体结构的动力特性分析          下载免费PDF全文

雷江 《地震工程学报》2018,40(3):432-437

传统低层建筑砌体结构动力特性分析中,易受到外界环境的干扰,砌体结构的完整性欠缺,导致动力特性分析的准确度较低。为提高低层建筑砌体结构的抗震性能,提出地震作用下低层建筑砌体结构的动力特性分析方法。首先利用低层建筑砌体结构反应自功率谱,完成砌体结构的自振频率辨认;然后通过941B型超低频率测振仪测试自振频率,筛出振动波形中噪声干扰的区域,获取时域波形和频域波形;最后依据时域波形和频域波形塑造低层建筑砌体三维精细化模型,在该模型基础上,通过子空间迭代算法获取低层建筑砌体结构的模拟结果,分析地震作用下芯柱、圈梁等构造措施对建筑砌体结构动力特征的影响,完成砌体结构的动力特性分析。实验结果表明,利用所提方法对地震作用下低层建筑砌体结构的动力特性进行分析,得到的分析结果准确度较高。  相似文献   

福建及其邻区背景噪声面波群速度层析成像     

张丽娜  罗艳  陈智勇  谢志招  周蓝捷  曾祥方 《地震》2018,38(3):134-143

基于福建及邻区108个宽频带地震台站2016年6月到7月两个月垂直和水平分量波形连续记录, 利用相位加权叠加算法提高信噪比, 计算得到108个台站对的高质量经验格林函数。 对所获取的经验格林函数, 采用时频分析的方法在1~20 s频段内量取了大量高质量的Rayleigh波和Love波群速度频散数据。 在此基础上, 采用基于射线追踪的二维层析成像方法反演得到了福建及其邻区1~20 s的Rayleigh波和Love波群速度分布。 分辨率测试结果表明群速度分布的分辨率能达50 km。 成像结果显示1~10 s的群速度分布与地壳中上部地质特征有很好的一致性, 区内的福州盆地和漳州盆地在浅层结构中表现出明显的低速异常。 长周期的群速度则揭示了漳州西北的高地热区内中下地壳低速体, 政和-大埔断裂两侧的速度差异, 表明其可能是一个深大断裂, 并呈现明显的东西差异。  相似文献   

日照市土壤地球化学元素分布规律及成因探讨          下载免费PDF全文

庞绪贵  宋娟娟  代杰瑞  喻超  张华平  陈磊  任天龙  王红晋 《山东国土资源》2018,34(4)

在日照市开展多目标区域地球化学调查，获取了表层土壤和深层土壤地球化学数据，通过对获得的地球化学参数进行统计分析，确定了日照市土壤地球化学基准值和背景值，认为日照市除部分元素或指标外，大部分元素或指标土壤地球化学基准值和背景值与全省土壤地球化学基准值和背景值接近。研究发现，日照市As，Cd，Cr，Cu，Hg，Ni，Pb，Zn等8种重金属元素背景值含量低于国家土壤环境质量标准的土壤一级标准限值，日照市土壤质量基本保持自然背景水平；而受工业化生产和城市化建设等后期人为活动影响，日照市表层土壤中Cd，C，Hg，N，P，S，Se，Corg等元素或指标出现明显富集，应引起重视。  相似文献   

Rare earth elements and yttrium in ferromanganese deposits from the South China Sea: distribution, composition and resource considerations     

ZHONG Yi  CHEN Zhong  GONZALEZ Francisco Javier  ZHENG Xufeng  LI Gang  LUO Yun  MO Aibin  XU Antao  WANG Shuhong 《海洋学报(英文版)》2018,37(7):41-54

Ferromanganese nodules and crusts contain relatively high concentration of rare earth elements(REE) and yttrium(REY),with a growing interest in exploitation as an alternative to land-based REY resources.On the basis of comprehensive geochemical approach,the abundance and distribution of REY in the ferromanganese nodules from the South China Sea are analyzed.The results indicate that the REY contents in ferromanganese deposits show a clear geographic regularity.Total REY contents range from 69.1×10~(–6) to 2 919.4×10~(–6),with an average value of 1 459.5×10~(–6).Especially,the enrichment rate of Ce content is high,accounting for almost 60% of the total REY.This REE enrichment is controlled mainly by the sorption of ferromanganese oxides and clay minerals in the nodules and crusts.Moreover,the total REY are higher in ferromanganese deposits of hydrogenous origin than of diagenetic origin.Finally,Light REE(LREE) and heavy REE(HREE) oxides of the ferromanganese deposits in the study area can be classified into four grades: non-enriched type,weakly enriched type,enriched type,and extremely enriched type.According to the classification criteria of rare earth resources,the Xisha and Zhongsha platform-central deep basin areas show a great potential for these rare earth metals.  相似文献   

中国火山温泉气体地球化学特征及其在火山监测中的应用     

魏费翔  许建东  上官志冠  潘波 《震灾防御技术》2018,13(4):938-949

中国火山温泉主要分布在吉林长白山、云南腾冲和黑龙江五大连池等火山区。这些火山虽然处于休眠状态，但大面积的温泉分布指示着岩浆房存在的可能性。本文总结了前人研究成果，分析了中国主要火山区温泉气体地球化学特征，并探讨了温泉气体在火山监测中的应用。长白山、腾冲和五大连池火山区温泉气体地球化学性质类似，都以CO₂为主要气体，含量在80%以上，最高可达99%以上，其它气体组分包括CH₄、N₂、O₂、SO₂、H₂S、He和H₂等。长白山火山温泉气体中氦同位素比值（3He/4He）最高，约为4—6R_A，CO₂中碳同位素比值（δ13C）为-7.9‰—-1.3‰，CH₄中碳同位素为-48.0‰—-28.7‰；腾冲火山温泉气体氦同位素比值为3—5.5R_A，CO₂中的碳同位素为-6.49‰—-2.07‰，CH₄中碳同位素为-23.5‰—-9.3‰；五大连池火山温泉气体氦同位素比值约为3R_A，CO₂中的碳同位素比值为-9.6‰—-3.1‰，CH₄中碳同位素为-47.2‰—-44.4‰。3个火山区的温泉气体均显示地幔来源的岩浆气体特征，并在上升运移过程中受地壳或古俯冲物质的影响。  相似文献