区域重力工作在煤田勘查中应用效果

据三塘湖勘查区区域重力勘查工作,推断断裂体系、局部构造和预测煤田,取得找煤突出效果,反映重力勘查具快速高效和有效性特点,对同类或相似地区煤田勘探工作具借鉴作用。     

Analysis of occurrence characteristics of geothermal resources and its relation to control structures in Zibo City,China

According to the geothermal geological conditions, the geothermal resources in Zibo can be divided into sedimentary basin type and tectonic basin type. The main thermal reservoirs of sedimentary basin type are the Neogene Guantao Formation and the Paleogene Dongying Formation.The thermal reservoirs of tectonic basin type are mainly the Ordovician Majiagou Group. The characteristics of reservoir, cap, pass and source of thermal resource types in different areas are elaborated. Based on the analysis of the well-forming conditions of the existing geothermal wells in the area, combined with the geothermal anomaly areas and hydrogeochemistry, it was discovered that the fault structures in the area, especially the deep faults such as Yuwangshan fault, Wangmushan fault, Zhangdian fault and Chaomizhuang graben, play an important role in controlling the occurrence and distribution of tectonic basin-type geothermal resources in Zibo City.     

Field investigations and laboratory simulation of clogging in Lixi tailings dam of Jinduicheng,China

Clogging is one of the most important factors affecting the stability of the tailings dams. Firstly, this work investigates the clogging materials of Lixi tailings dam using ICP-AES, X-ray powder diffraction (XRD) and SEM analysis methods. The ICP-AES results indicate that Fe is the dominant element in the clogging materials. The iron contents of clogging samples collected from 2# radial-well pipe and the access hole of the starter dam are 54.35 and 40.24%, respectively. XRD spectra show that ferric hydroxide is the main initial component of the clogging materials. Other compounds such as akaganeite, hematite and goethite are products from ferric hydroxide transformation. Therefore, the clogging materials are a mixture of ferric hydroxide and its converted products. The clogging materials commonly exist in an amorphous form with a cluster microstructure when viewed under SEM. Secondly, this work uses a continuous flow column to simulate clogging in the laboratory, and the clogging materials are analyzed with XRD and SEM. The chemical analysis indicates that the iron content of the clogging materials from the experiment is 45.43%. XRD spectra show that hematite is the only compound detected. The clogging materials generated experimentally are also in amorphous cluster microstructure when viewed under SEM.     

Fault Zone Fluid Deep-penetrating Techniques for Potash Deposit Prediction in Lanping-Simao Basin,Yunnan,South China

正In China,the strategic resource potash is suffering from severe shortages,and the ancient marine solid potash locating is still a problem of long impregnability.Till now,only the Mengyejing Potash Deposit was found     

北京南部地区地面沉降发育特征及成因分析

本文总结了北京市南部地区地面沉降的发育特征,主要对区内地面沉降的历史,现状和垂向发育特征,进行了总体描述,分析了地面沉降成因,对区内今后的工程建设提出了合理化建议。     

硝态氮对库区水体藻类和细菌群落的影响

水体富营养化极易引起湖泊水库如藻类水华等水生态系统环境问题。氮素作为初级生产力的限制性生源要素之一,认识其在水华形成过程中潜在作用至关重要。本研究选取胶东半岛低碳高氮水库水体进行模拟实验,通过添加不同剂量硝态氮,探究高硝态氮输入对库区水体藻类和细菌群落结构的影响。结果表明:(1)当硝态氮作为唯一氮源,随着培养时间延长,硝态氮浓度显著下降,亚硝态氮和氨氮浓度逐渐升高,表明微藻和细菌共同作用可能将硝态氮转化为亚硝态氮和氨氮;(2)当硝态氮浓度为6 mg/L时,藻类叶绿素a浓度达到最高值,随着硝态氮浓度升高,叶绿素a浓度则会降低;(3)添加硝态氮后,蓝藻门成为优势藻类,绿藻门次之;变形菌门相对丰度显著升高。研究结果为低碳高氮类水体暴发蓝绿藻水华及有效防控提供理论依据和技术支撑。     

川滇甘陕地区地震的加速度峰值比和竖向反应谱的统计分析

本文以国内川滇甘陕地区263个有详细场地资料的强震台站获得的802组地震动加速度记录为基础,研究了该地区加速度峰值比的总体分布特征,分别探讨了震中距和震级对加速度峰值比的影响特征,按照水平反应谱的标定方法对竖向反应谱进行标定并对其进行了统计分析。统计分析结果显示:竖向与水平向加速度峰值比的概率分布总体服从极值Ⅱ型分布,加速度峰值比均值为0.6,加速度峰值比≤0.65的累积频率为64%;Ⅱ类场地的加速度峰值比随震中距增大而减小;大震近场的加速度峰值比基本上远高于0.65;最后本文给出了不同场地类别下竖向反应谱特征参数,并与水平向反应谱特征参数进行了比较。     

一种改进的SIFT描述子及其性能分析

为了解决传统SIFT描述子在图像存在多个相似区域时易造成误匹配的问题,提出了一种改进的SIFT描述子及其生成方法。该方法通过构建尺度空间、检测极值点、确定关键点等步骤生成关键特征点,然后计算每个关键点周围图像区域的旋转不变纹理特征作为该关键点的描述,并将其融合到局部特性SIFT描述向量中,形成旋转不变纹理化SIFT描述子,并采用了两种不同的匹配策略应用于图像匹配,实验结果表明,本方法更加全面地描述了图像信息,有效提高了SIFT算法匹配准率,改善了匹配效果,实现了对SIFT算法的改良。     

2019年山东夏季降水异常特征及成因分析

2019年夏季山东平均降水量为414.6 mm,较常年偏多3.0%。降水过程较少,时空分布不均,降水偏多主要是由台风“利奇马”影响所致,如果去除台风降水,夏季平均降水量较常年偏少41.8%。夏季西太平洋副热带高压持续偏强、偏西、偏南,配合欧亚中高纬的“两槽一脊”环流型,是去除台风影响后造成山东夏季降水明显偏少的直接原因;2018年9月至2019年6月的厄尔尼诺事件和热带印度洋海面温度的持续偏高对西太平洋副热带高压偏强、偏西、偏南起到重要作用;北大西洋海面温度三极子持续的正位相与贝加尔湖高压脊偏强有着密切联系。     

黄河源区白河基流分割方法适用性分析

基流是黄河径流的重要补给来源, 对源区水资源规划和生态环境建设具有重要作用。以黄河源区白河流域为研究区, 利用唐克水文站1981 - 2015年的实测日径流资料, 采用常用的5类12种数值模拟法, 进行基流分割并比较分析其适用性。结果表明： 12种方法估算的基流指数（Baseflow index, BFI）差异明显, Lyne-Hollick滤波法计算的BFI值最大, 为0.91; 加里宁法计算的BFI值最小, 为0.39; Eckhardt滤波法的标准差和极值比最小, 稳定性最好; 加里宁法的标准差和极值比最大, 稳定性最差; 对1992年（丰水年）日径流过程进行分割, Chapman滤波法、 Chapman-Maxwell滤波法和加里宁法的基流过程线平滑缓慢, 更符合实际情况; Boughton-Chapman滤波法、 BFI法和HYSEP法基流模拟效果较好, Nash-Sutcliffe效率系数高于0.87, 决定系数接近0.9, 平均相对误差小于10%。综合比较, 认为Boughton-Chapman滤波法、 BFI法是白河流域较为适宜的基流分割手段。