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121.
地质资料目录查询系统的设计与实现   总被引:1,自引:0,他引:1  
地质资料目录查询系统主要针对地勘单位地质资料管理现状进行研究,采用VS2010开发环境,SQL Server2008、.NET4.0框架、B/S架构等关键技术.设计提供报告查询、报告录入、报告维护、服务器连接、用户管理五大功能模块,提高了地质资料整理与查询的效率,实现对地质资料进行科学化、信息化管理.  相似文献   
122.
童馗  邢立达  姜巽  彭光照  叶勇  江山  丑春永  李轲  李智武 《地质通报》2018,37(10):1771-1776
四川西昌盆地白垩系小坝组尚未发现骨骼化石记录,其白垩系恐龙动物群的信息全赖于足迹化石。2017年,在喜德县洛甘发现小坝组迄今最大型的恐龙足迹群。该足迹点保存了大量的兽脚类足迹。足迹保存条件较差,但具备了基本的形态学特征。总体来看,兽脚类足迹具有尺寸较小(8~13cm),中等中趾前凹(0.5~0.6)和第Ⅱ趾和第Ⅳ趾间较宽趾间角(70°~100°)的特征;少量足迹保存了跖骨垫。初步分析认为,洛甘兽脚类足迹与四川盆地夹关组的兽脚类足迹Eubrontes和Grallator形态类型相似,为两地在白垩纪中期具有类似的恐龙动物群的观点提供了新的证据。该发现对于西昌盆地的古气候、古地理和地层对比都具有重要的意义,足迹详细分类还有待进一步研究。  相似文献   
123.
在滇东南富宁地区基性侵入岩、喷出岩较发育,前人将其划分为"半瓦型"侵入岩、"安定型"侵入岩和"龙康型"喷出岩3类,3类岩石普遍缺乏可靠的同位素年代学资料。在对富宁地区基性侵入岩、喷出岩进行区域地质调查的基础上,应用LAICP-MS技术对其进行锆石U-Pb测年,在半瓦型侵入岩和安定型侵入岩中分别获得了254.0±2.0Ma和244.2±4.4Ma的加权平均年龄,在龙康型喷出岩中获得251.9±3.0Ma和255.92±0.72Ma加权平均年龄。结合野外调查和综合研究,将富宁地区"安定型"侵入岩的时代界定于中三叠世,将"半瓦型"侵入岩和"龙康型"喷出岩的时代界定于晚二叠世。  相似文献   
124.
An oil-based drilling fluid additive H-DEA (or humic acid-cocamide diethanolamine) was synthesised using humic acid and cocamide diethanolamine as raw materials. The rheological behaviors of H-DEA showed that the synthesised product has the good properties in both decreasing the filtrate loss and improving rheology property of oil-based drilling fluids compared with other commercially available additives. Under the optimal additive amount of 3%, both API filtrate loss and yield point changed remarkably from 5.40 to 0.41 mL and 9.0 to 25.6 Pa, respectively. Furthermore, differential scanning calorimetry (DSC) showed that H-DEA has good thermal stability in a wide temperature range up to 170 °C. Infrared spectroscopy (IR) and rheological analysis revealed that the possible mechanism of the multifunctional effects may be attributed to the existing of high density of strong polar groups, hydrogen bonds, electrostatic forces, and intermolecular association on H-DEA molecular structure. The results of the study showed that the synthesised H-DEA can be potentially used as a multifunctional oil-based drilling fluid additive in oil-drilling excavation.  相似文献   
125.
The no. 11 coal seam in the deep area of Hancheng mining area is mining in recent years, which is threatened by the water inrush from the Ordovician limestone aquifer. Coal-floor water inrush is governed by the water abundance of coal-floor aquifer, the water-resisting performance of coal-floor aquitard, and the pathway connecting the water source and the working face. To make an accuracy risk assessment of water inrush from the no. 11 coal seam floor, a GIS-based vulnerability index method (VIM) is adopted for its superior comprehensive consideration of more controlling factors, powerful spatial analysis, and intuitively display functions. This study firstly established an index system including the water pressure of the coal-floor aquifer, the unit water inflow, the thickness, the core recovery percentage, the thickness ratio of brittle rocks to ductile rocks, the thickness of effective aquitard, and the accumulated length of faults and folds, of which the former six indexes governed the water abundance of the coal-floor aquifer which was combined with the last two factors to determine the risk of coal-floor water inrush. Secondly, the thematic map of each controlling factor is established by GIS using the geological prospecting data, and the weight of each factor is determined by the analytic hierarchy process (AHP) after consulting the expert review panel. At last, a vulnerability index is obtained and used to assess the risk of coal-floor water inrush of the no. 11 coal seam. The risk of water inrush of the no. 11 coal seam of the study area was ranked to three zones: the southeastern shallow area in red color is the dangerous zone, the wide northwestern area in green color is the safe zone, and the transition area in yellow color is the moderate-risk zone. Compared with the actual water-inrush incidents, the risk assessment result was verified to achieve an accuracy of 82.35%, which is proved to be a dependable reference for the prevention and controlling of coal-floor water inrush of the no. 11 coal seam in Hancheng mining area.  相似文献   
126.
渝东北城口地区Y1井页岩有机地球化学特征及勘探前景   总被引:1,自引:0,他引:1  
基于钻井资料,以总有机碳(TOC)、干酪根显微组分、等效镜质体反射率(Ro)及碳同位素等测试数据系统分析了渝东北城口地区Y1井五峰组—龙马溪组页岩的有机地球化学特征,利用页岩流体包裹体的显微特征、均一温度及激光拉曼数据深入分析了Y1井页岩气成藏特征。结果表明:Y1井上奥陶统五峰组—下志留统龙马溪组炭质页岩发育,TOC含量2%的富含有机质页岩厚度达83 m,干酪根类型以Ⅰ型干酪根为主,处于湿气生烃阶段。页岩裂缝脉体中大量烃包裹体和富含甲烷气体的含烃盐水包裹体证实城口地区五峰组—龙马溪组页岩发生了充足页岩气供给,具有高均一温度、高盐度的伴生盐水包裹体表明城口地区页岩气成藏时期的保存条件良好。这些Y1井页岩有机地球化学特征研究成果揭示了城口地区下古生界具备良好的页岩气勘探前景。  相似文献   
127.
This exploratory study contributes to our knowledge about the relationships between interpersonal communication sources and risk perception regarding natural hazards. Survey data (N?=?186) from a small village in northwest China was used, and the correlations between eight types of interpersonal communication sources related to disaster risk reduction and the perceived severity and perceived likelihood of occurrence of eight types of natural hazards were explored. Past studies have suggested that interpersonal communication sources are more likely to influence individuals in their perceived severity of natural hazards than in their perceived likelihood of occurrence. The results of this study moderately corroborate this finding. The results indicated that different sources have different relationships to risk perception, as positive correlations were found between obtaining information via certain trained science professionals (science teachers, emergency responders, scientific experts) and certain natural hazard risk perceptions, while negative relationships were found between obtaining information via certain personal contacts (other villagers and relatives and friends) and certain natural hazard risk perceptions. However, the strength of these relationships was weak (??0.197?≥?r?≤? 0.245). Age showed statically significant correlations with the perceived severity of most of the natural hazards. Studies with more representative samples and controls for theoretical factors are needed to better understand how interpersonal communication sources affect individuals' natural hazard risk perceptions.  相似文献   
128.
本文对青海南山吾口正长花岗岩和花岗闪长岩进行了岩石学、岩石地球化学及年代学研究。首次测得吾口侵入岩体正长花岗岩的锆石206Pb/238U年龄为253. 8±3. 3Ma(MSWD=0. 96),形成时代为晚二叠世。岩石中Al_2O_3为(14. 13~16. 51)×10~(-2),K_2O为(1. 66~3. 59)×10~(-2),A/NK=1. 15~2. 35,A/CNK=0. 75~1. 03,TFe O/(TFe O+MgO)=0. 53~0. 81,岩石具偏铝质中-高钾钙碱性花岗岩特征;吾口岩体表现为富集大离子亲石元素Rb、K等,亏损高场强元素Nb、Ta、Ba等;轻重稀土分异较明显,具右倾特征,中等负Eu异常(δEu=0. 44~0. 68),具壳幔岩浆混合特征。吾口岩体代表了阿尼玛卿洋盆向北削减俯冲运动在青海南山构造带与西秦岭造山带和南祁连造山带的构造转换衔接部位的构造演化的地质记录。该侵入岩体形成时代及构造环境的确定,为研究印支早期青海南山构造演化及动力学机制提供重要依据。  相似文献   
129.
以江西省某县地理国情普查数据为基础,研究其与土地变更调查数据的相似性与差异性,结合土地资源监测的热点,初步探究地理国情普查成果在土地资源监测中应用,为地理国情普查成果应用提供思路与方向。  相似文献   
130.
针对GPS定位系统及IMU惯性测量导航在航空摄影测量发挥的巨大作用,本文阐述了GPS-IMU组合辅助航空摄影测量的基本原理和方法,分析了此项技术的主要误差来源,并对提高精度提出了可行性方案。该方案有助于航空摄影单位对此技术的学习和研究,并且在日常生产中灵活、高效地发挥此技术的优势[1]。  相似文献   
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