营盘圩矿点区域地质背景分析

正研究区营盘圩矿点位于桃山—褚广铀成矿带南西端,为花岗岩硅质脉型矿点。桃山—褚广铀成矿带是我国最大的花岗岩型铀成矿带,该成矿带诸广岩体内集中产出了鹿井、长江、百顺铀矿田。前人在矿床的成因和成矿规律、岩体演化、岩石地球化学特征、控矿因素、矿化和蚀变等方面取得了较多成果(李建红等,2006;曾文乐等,2006;杜乐天等,1982;余金达等,1988),本文在前人勘查     

中国洞穴生物研究概述

本文评述了中国洞穴生物的研究历史、现状,概括了研究内容,总结了近20年来中国在洞穴生物研究方面所取得的成果,在充分分析洞穴生物研究动态并列举了大量的文献资料后,展望了中国洞穴生物研究的前景。      

安徽安庆M_S4.8级地震现场调查启示与震害特征分析

本文通过安庆MS4.8级地震现场调查和震害特征分析,探讨了5.0级左右中强地震现场调查的自身安全保障、灾民恐惧心理安抚,以及震害分布、震害损失、人员伤亡等,旨在为将来5.0级左右中强破坏性地震开展现场调查和研究震害特征等提供参考。     

Suitability of data preprocessing methods for landslide displacement forecasting

Stochastic Environmental Research and Risk Assessment - Data preprocessing is an indispensable step for landslide displacement forecasting, which is an effective approach for predicting the...     

Effect of extracellular polymeric substances on the phosphorus adsorption characteristics of sediment particles

Extracellular polymeric substances (EPS) have a great impact on the characteristics of sediment particles and their environmental effects in hydro-environmental systems, yet little effort has been made to study the considerable variability in the element adsorption process of sediment particles caused by EPS. Understanding the variability of the adsorption characteristics of sediment particles associated with EPS and quantifying the scale of the adsorption isotherm parameters are important for understanding how EPS mediate sediment properties and environmental factors. In this paper, isothermal equilibrium adsorption experiments are done on phosphorus to study the influence of EPS on the adsorption characteristics of sediment particles, and the Langmuir adsorption isotherm is applied to analyze the adsorption rule of sediment particles under the impact of EPS. The current research demonstrates that significant differences will take place in the adsorption characteristics of sediments coated with EPS at different development phases and the phosphorus adsorption capacity of sediment particles increases with the growth of EPS. The difference in the adsorption percentage between sediment particles coated with EPS of 0 and 6 weeks growth time is about 42%–60% for different initial aqueous phosphorus concentration. A formula describing the adsorption isotherm parameter of the maximum material (element) adsorption capacity of sediment particles change over time is further proposed based on the experimental data. The current study provides some evidence for the interaction of sediment particles, EPS, and adsorbed elements in the water environment.     

Why Does Extreme Rainfall Occur in Central China during the Summer of 2020 after a Weak El Ni?o?

In summer 2020, extreme rainfall occurred throughout the Yangtze River basin, Huaihe River basin, and southern Yellow River basin, which are defined here as the central China (CC) region. However, only a weak central Pacific (CP) El Ni?o happened during winter 2019/20, so the correlations between the El Ni?o–Southern Oscillation (ENSO) indices and ENSO-induced circulation anomalies were insufficient to explain this extreme precipitation event. In this study, reanalysis data and numerical experiments are employed to identify and verify the primary ENSO-related factors that cause this extreme rainfall event. During summer 2020, unusually strong anomalous southwesterlies on the northwest side of an extremely strong Northwest Pacific anticyclone anomaly (NWPAC) contributed excess moisture and convective instability to the CC region, and thus, triggered extreme precipitation in this area. The tropical Indian Ocean (TIO) has warmed in recent decades, and consequently, intensified TIO basinwide warming appears after a weak El Ni?o, which excites an extremely strong NWPAC via the pathway of the Indo-western Pacific Ocean capacitor (IPOC) effect. Additionally, the ENSO event of 2019/20 should be treated as a fast-decaying CP El Ni?o rather than a general CP El Ni?o, so that the circulation and precipitation anomalies in summer 2020 can be better understood. Last, the increasing trend of tropospheric temperature and moisture content in the CC region after 2000 is also conducive to producing heavy precipitation.     

决策树方法在一次历史异常雷电活动中的预报能力检验

利用ncep1°×1°再分析资料和四川闪电定位仪监测网的监测资料,基于四川雷电潜势预报决策树的三类预报因子,针对2008年9月22～25日四川盆地西北部连续性雷电活动过程,重点分析了连续性雷电活动的环流背景和主要天气影响系统、热力结构特征、动力结构特征,检验了基于决策树方法筛选出的雷电潜势预报因子对连续性雷电活动的预报能力.结果表明：1）“9·23”连续性雷暴天气过程存在对流性雷暴以及副高和地面冷空气共同作用下形成的雷暴时段.雷暴区内始终存在着高能不稳定的热力条件,具有“对流层中低层正涡度、对流层高层负涡度”的典型雷暴动力结构.2）雷电潜势预报决策树的三大类预报因子能较好地预报本次雷电活动.     

Surface Microtextures of Slipping Zone Soil of Some Landslides in the Three Gorges Reservoir District and Their Significance

The mineral assemblage and content and surface microtextures of slipping zone soil of several landslides in the Three Gorges Reservoir District have been analyzed using the scanning electron microscope (SEM) and X-ray diffractometer (XRD). All the mineral assemblages are similar in these landslides. The main minerals are montmorillonite, illite, kaolinite, chlorite, quartz and feldspar. There are two kinds of surface microtexture in the slipping zone soil, i.e., linear scratches and arcuate scratches. Based on analyses of the changes of the microtextures, one can obtain information about the number, directions and stages of landslide movements. The authors have also studied the mechanism of landslide formation, evaluated the stability of landslides and revival possibility of ancient landslides and forecasted the activity of similar landslides in different districts. The surface microtexture features of stable landslides and mobile landslides are summarized and it is concluded that the existence of filam     

地质环境与城市发展研究综述

该文概述了城市地质环境与城市发展国内外研究现状,指出了我国城市工程地质工作存在的问题,论证了地质环境与城市发展中主要问题的解决途径,提出了地质环境与城市发展研究与工作的一些建议。论文还介绍了与地质环境与城市发展密切相关的我国工程地质专业设置现状与发展趋势。