三塘湖盆地石炭系卡拉岗组火山岩岩相研究

三塘湖盆地石炭系卡拉岗组火山岩岩性揭示该区火山岩岩相主要包括火山爆发相、溢流相,火山沉积相不发育。为了明确不同岩相分布规律,本文系统利用测井、地质、地震等多种资料,建立测井岩性识别模板,以单井相作为约束,开展地震反演,明确火山岩岩相的平面分布规律。研究结果表明:该区火山喷发方式以裂隙式为主,火山口呈串珠状沿主断裂排列;溢流相平面呈层状分布,溢流相安山岩最为发育。研究结果可有效指导该区火山岩油藏的勘探评价工作,同时为火山岩岩相研究提供可借鉴的研究思路。     

印度区域地质矿产概况

印度共和国是印度板块的主体,也是冈瓦纳大陆的重要组成部分,主要由七个古老克拉通（陆块群）、分隔克拉通的活动带与盆地等构成。自北向南依次为：①喜马拉雅活动带,主要为具有元古代基底的古近纪-新进纪活动带;②印度河-恒河平原过渡带（山前坳陷带）,主要由为第四系、古近系-新进系和第四系冲积物构成;③印度半岛克拉通,主要由西塔尔瓦尔、东塔尔瓦尔、巴斯塔、辛本,本德尔坎德、阿拉瓦利和印度南部麻粒岩地体等7个太古宙陆块（或次级克拉通）群构成;④萨德布尔活动带;⑤东高止山活动带;⑥德干高原玄武岩省（LIP）（图1）。     

ZQZ TF型风传感器冻结故障自动检测装置设计

近年来我国大部分地区在冬、春两季多遭受冻雨灾害,自动气象站的风向风速传感器容易因冻结而无法正常工作。针对冻结故障的实时检测问题,本文设计了一种基于ZQZ-TF型风传感器的故障自动检测装置。该装置通过检测风传感器的工作电压和工作电流,实现对传感器实时状态的监控。同时,结合具体的故障诊断算法,能够快速判断风传感器是否被冻结。系统的核心硬件电路、软件算法可分别集成在自动气象站风向风速数据采集电路和嵌入式软件中,具有结构紧凑、操作简单的特点。经验证,该装置能够实时检测风传感器冻结故障,且工作稳定,检测精度高。     

辽东湾坳陷东部地区走滑双重构造的发育特征 及其石油地质意义

在将构造发育特征与走滑双重构造理论模型进行类比分析的基础上,对辽东湾坳陷东部地区的走滑双重构造的发育特征进行了研究,并结合油气勘探实践成果,就其石油地质意义进行了探讨,研究结果表明:在受控于走滑与拉伸并存的多动力源区域地质背景下,辽东湾坳陷新生代构造演化体现了断陷与拗陷、拉张与走滑的叠加效应,NNE走向的辽中1号断裂、辽中2号断裂及辽东断裂的发育不仅控制了辽东湾坳陷东部地区的凸凹格局,其走滑侧接关系也导致了研究区走滑双重构造的发育;辽东凸起是由于辽中2号断裂、辽东断裂走滑弯曲、右行左阶侧接而形成的挤压走滑双重构造,而辽中凹陷在早期拉张断陷基础上,经历了后期走滑作用的改造,其断裂体系的发育体现了辽中1号断裂与辽中2号断裂的右旋右行侧列所产生的拉张走滑双重构造效应;在走滑双重构造的增压带,断裂侧向封堵性强,有利于形成有效的断层圈闭,是油气藏发育的有利区带。     

多源卫星重力场模型精度与频谱分析

针对新一代卫星重力探测技术对地球重力场的频谱贡献问题,该文提出了一种基于GPS/水准数据获取多源卫星重力场模型频谱变化特征的方法。采用GPS/水准外符合检验,有效分析评估了多源卫星重力场模型在中国东、西部地区的精度水平。研究结果表明,以CHAMP、GRACE和GOCE卫星为代表的高-低卫星跟踪卫星、低-低卫星跟踪卫星和卫星重力梯度技术,对地球重力场的频谱贡献分别集中在600km以上的长波和中长波、300km以上的中波、200~350km之间的中短波部分。     

宁波市地下空间开发利用地质环境制约因素研究

地质环境条件是制约地下空间开发利用的最基本因素,只有正确认识地下空间开发对地质环境的影响,才能避免地下空间利用中产生的各种不利后果。基于对宁波市地质环境背景条件的认识,分别从水文地质条件、工程地质条件和环境地质问题等三个方面,研究了地下空间开发利用的影响因素。研究结果表明,水文地质条件的制约因素有孔隙潜水位埋深、含水层厚度、岩土层透水性能和基坑突涌可能性等;工程地质条件的制约因素有软土厚度、人工填土厚度、土质均匀性和地层组合等;主要环境地质问题为地面沉降和浅层天然气影响等。通过本次研究,为宁波市地下空间开发利用地质环境适宜性评价奠定了基础,为宁波市地下空间的合理开发利用提供了技术支撑。     

Regional debris flow susceptibility analysis based on principal component analysis and self-organizing map: a case study in Southwest China

A method was developed to analyze the susceptibilities of 541 regional basins affected by debris flows at the Wudongde Dam site in southwest China. Determining susceptibility requires information on source material quantity and occurrence frequency. However, the large number of debris flows can hinder the individual field investigation in a each small basin. Factors that may trigger debris flows can be identified using remotely sensed interpretation information. Susceptibility analysis can then be conducted based on these factors. In this study, SPOT5 satellite imagery, digital elevation models (DEM), a lithology distribution map, and rainfall monitoring data were used to identify 12 debris flow trigger factors: basin relief ratio, slope gradient in the initiation zone, drainage density, downslope curvature of the main channel, vegetation coverage, main channel aspect, topographic wetness index, Melton’s ruggedness number, lithology, annual rainfall, form factor, and cross-slope curvature of the transportation zone. Principal component analysis was used to obtain the eight principal components of these factors that contribute to susceptibility results. Then, a self-organizing map method was adopted to analyze the principal components, which resulted in a debris flow susceptibility classification. Field validation of 26 debris flow basins was used to evaluate the errors of the susceptibility classification, as well as assess the causes of such errors. The study found that principle component analysis and self-organizing map methodologies are good predictors of basin susceptibility to debris flows.     

An artificial neural network-based response surface method for reliability analyses of <Emphasis Type="Italic">c</Emphasis>-φ slopes with spatially variable soil

This paper presents an artificial neural network (ANN)-based response surface method that can be used to predict the failure probability of c-φ slopes with spatially variable soil. In this method, the Latin hypercube sampling technique is adopted to generate input datasets for establishing an ANN model; the random finite element method is then utilized to calculate the corresponding output datasets considering the spatial variability of soil properties; and finally, an ANN model is trained to construct the response surface of failure probability and obtain an approximate function that incorporates the relevant variables. The results of the illustrated example indicate that the proposed method provides credible and accurate estimations of failure probability. As a result, the obtained approximate function can be used as an alternative to the specific analysis process in c-φ slope reliability analyses.     

The characteristics of rill development and their effects on runoff and sediment yield under different slope gradients

Rill formation is the predominant erosion process in slope land in the Loess Plateau, China. This study was conducted to investigate rill erosion characteristics and their effects on runoff and sediment yielding processes under different slope gradients at a rate of 10°, 15°, 20° and 25° with rainfall intensity of 1.5 mm min-1 in a laboratory setting. Results revealed that mean rill depth and rill density has a positive interrelation to the slope gradient. To the contrary, width-depth ratio and distance of the longest rill to the top of the slope negatively related to slope gradient. All these suggested that increasing slope steepness could enhance rill headward erosion, vertical erosion and the fragmentation of the slope surface. Furthermore,total erosion tended to approach a stable maximum value with increasing slope, which implied that there is probably a threshold slope gradient where soil erosion begins to weaken. At the same time, the correlation analysis showed that there was a close connection between slope gradient and the variousindices of soil erosion: the correlation coefficients of slope gradient with maximal rill depth, number of rills and the distance of the longest rill from the top of the slope were 0.98, 0.97 and-0.98, respectively,indicating that slope gradient is the major factor of affecting the development of rills. Furthermore,runoff was not sensitive to slope gradient and rill formation in this study. Sediment concentration,however, is positively related to slope gradient and rill formation, the sediment concentrations increased rapidly after rill initiation, especially. These results may be essential for soil loss prediction.     

中国“四纵四横”高铁网络可达性综合评估与对比

传统测算可达性的方法较为单一,缺乏多层面、多角度的综合研究和对比分析。基于时间、经济与重心视角利用可达性模型并结合ArcGIS 空间分析手段探究高铁通车前后沿线城市可达性的动态变化;利用综合变异系数、层级分析法和改进的哈夫模型分析高铁可达性空间演变特征及规律,构建高铁可达性评价体系并结合熵权法定量评估各高铁可达综合实力。研究表明：京广、京沪可达综合实力最强,沪昆、杭福深次之,沪汉蓉、哈大、青太再次之,郑西、兰新可达实力最弱;全国高铁可达性强弱变化呈明显地带性规律,东、中部高铁可达性强于东北,东北强于西部,纵向高铁强于横向;经济潜力的增加率明显高于加权平均旅行时间的减少率,可达性重心偏移驱使不同等时圈蔓延交叠;高铁以“核心—核心”逐步向“核心—网络”空间链接模式过渡,产生上海、北京、广州、深圳4 个高铁“国家服务中心”,天津、武汉、重庆等6 个“大区域服务中心”,形成“多中心”高铁服务格局以及日益庞大而复杂的高铁特质空间集群;高铁网络影响下的中国区域空间格局的渐变与重塑日趋复杂,“T”型轴带呈现出由空间极化向空间均衡转变,跨城流动性特征突显,加速空间对接与同城化进程。