Google地图应用之广东省地区JOPENS地震速报系统

利用Google公司提供的电子地图服务,以B/S结构(即浏览器和服务器结构)作为系统设计架构,监听JOPENS实时系统发送的地震触发消息,访问JOPENS数据库,根据广东省地区的监测要求,制定检索、筛选策略,获取地震详细信息,显示在浏览器网页上.采用Google地图的JOPENS地震速报系统可以使地震信息发布的显示内容...     

山西交城水峪贯区域构造及地貌形成因素分析

交城水峪贯区域地质构造复杂,三大岩类齐全,岩浆岩类发育,岩层露头特征明显,并伴有煤、铁等矿产分布。区内主要发育NNW、NNE、SN向构造体系,从构造、地貌、地层及岩浆岩等因素分析,本区域经历了多次地质构造运动,对其影响最大的为燕山运动。在早燕山期构造运动中近EW向的主应力作用下形成了本区域古洞道向斜、鲁沿向斜、山前大断裂等构造及狐偃山六大岩浆岩体,后期受应力转变造成本区域X型剪节理发育及构造扭曲等现象。形成了本区域现代地质构造及地貌轮廓。     

青海省天峻县木里煤田聚乎更矿区构造轮廓和地层格架

木里煤田聚乎更矿区是全球陆上中纬度、高海拔冻土带天然气水合物的发现地,也是当前青藏高原地质研究的热点地区之一。依据近年来的煤炭地质勘查资料,对聚乎更矿区的构造轮廓、含煤地层、沉积相和聚煤作用进行深入分析．认为聚乎更矿区位于祁连坳褶带西段,受大通山北缘和托莱山南缘对冲断裂组的制约,构造线总体方向为北西一南东向,构造轮廓表现为南北2个向斜,其中北向斜的煤炭赋存条件优于南向斜。聚乎更矿区含煤地层为中侏罗统木里组和江仓纽。主要可采煤层赋存于木里组上段,聚煤作用主要发生于木里组沉积期的辫状河淤浅之后发育的泥炭沼泽和湖泊、水下三角洲淤浅而发育的泥炭沼泽。     

Effect of flying altitude and pulse repetition frequency on laser scanner penetration rate for digital elevation model generation in a tropical forest

In tropical forests, the penetration ability of airborne laser scanning (ALS) may be limited because of highly dense vegetation cover. However, in the typical planning of ALS surveys, the ability of laser pulses to penetrate forests is not considered. Nine round-trip flight lines covering the area of a tropical forest on the northeast side of the Tsengwen Reservoir in Taiwan were designed in this study. Five flight lines flew at altitudes of 1.525, 1.830, 2.135, 2.440, and 2.745 km, and the other four had pulse repetition frequencies (PRFs) of 100, 150, 200, and 250 kHz. The laser penetration index (LPI) is a quantitative index measuring the penetration ability of the ALS and consists of the ratio of the number of laser pulses reaching the forest floor to the total number of laser pulses. The LPI was used to represent the laser penetration rate and investigate the influence of flying altitude and PRF on the LPI. The results showed that as the flying altitude decreased by 1 km, the average LPI increased by 10%, and as the PRF decreased by 50 kHz, the average LPI increased by 2%. The effect of the LPI on digital elevation models (DEMs) was confirmed by visual images obtained by DEMs at five altitudes. The DEM obtained at an altitude of 2.745 km was coarsely textured, whereas that obtained at an altitude of 1.525 km was finely textured. The in-situ height data obtained from the electronic Global Navigation Satellite System (eGNSS) were compared with the data of the ALS-generated DEMs. The results indicated that when the LPI ≥60%, the height difference between the in situ data and DEM data was not prominent. However, when the LPI <60%, the ALS-derived DEM could be higher or lower than the in-situ height; the largest difference between the two was 1.7 m. The LPI of a forest should be considered for ALS survey planning, especially when consistent DEM precision for large tropical forest areas is paramount.     

Idealisation of soil–structure system to determine inelastic seismic response of mid-rise building frames

In this study, a novel and enhanced soil–structure model is developed adopting the direct analysis method using FLAC 2D software to simulate the complex dynamic soil–structure interaction and treat the behaviour of both soil and structure with equal rigour simultaneously. To have a better judgment on the inelastic structural response, three types of mid-rise moment resisting building frames, including 5, 10, and 15 storey buildings are selected in conjunction with three soil types with the shear wave velocities less than 600 m/s, representing soil classes C_e, D_e and E_e, according to Australian Standards. The above mentioned frames have been analysed under two different boundary conditions: (i) fixed-base (no soil–structure interaction) and (ii) flexible-base (considering soil–structure interaction). The results of the analyses in terms of structural displacements and drifts for the above mentioned boundary conditions have been compared and discussed. It is concluded that considering dynamic soil–structure interaction effects in seismic design of moment resisting building frames resting on soil classes D_e and E_e is essential.     

致密砂岩气藏可动流体赋存特征的微观地质因素: 以苏里格气田东部盒8段储层为例

以苏里格气田东部盒8段典型的致密砂岩气藏为例,运用核磁共振、恒速压汞、铸体薄片、物性、X-衍射等实验资料,探讨了影响可动流体赋存差异的微观地质 因素。结果表明,盒8段储层可动流体饱和度低,T₂谱分布均为左高峰右低峰的双峰态;黏土矿物的充填与孔隙类型是孔隙结构复杂的重要因素,孔隙结构是影响可动流体赋存特征的关键;面孔率、喉道 半径、孔喉半径比是影响可动流体饱和度的主要因素,有效孔隙体积、分选系数对可动流体饱和度影响明显,储层物性、黏土矿物、有效喉道体积、孔隙半径对可动流体饱和度影响较弱。     

南天山基性麻粒岩中变形石英和石榴子石的TEM研究

基性麻粒岩产于大陆地壳深部,它的研究可以为大陆岩石圈的性质、组成、演化和深部动力学过程提供重要信息。南天山库米什榆树沟地区发育总厚达1000多米的基性麻粒岩构造岩片,走向南东,朝北东推覆。剖面上和石炭纪蛇绿混杂岩共存,并发生了石榴子石的旋转变形和强烈的石英-长石矿物相韧性变形。然而它们的变形条件至今尚未被研究。本文运用透射电镜(TEM)超微组构技术对榆树沟基性麻粒岩中石英和石榴子石进行了详细研究,结果表明,石英中存在着丰富的超显微变形构造,自由位错、亚颗粒和位错网非常发育,这表明研究区基性麻粒岩在折返抬升过程中曾遭受过较强的石英-长石相韧性变形作用;石榴子石中的超微变形构造则极为少见,只在其中发现几根自由位错,并在其颗粒边缘发现少量亚颗粒构造,说明该矿物主体属于脆性变形。这两种矿物变形性质的差异,反映了石榴子石的晶体结构在该条件下比石英更稳定,而且说明石榴子石的变质温度没有超过900℃,也就是说,本区麻粒岩的变质作用并非发生在极高温度的条件下。     

旅游空间经济地租结构及其优化研究——以香格里拉二日游为例

旅游空间"经济地租"是衡量旅游空间消费效用(对于旅游者)或资本积累强度(对于资本)的重要指标。以香格里拉二日游为例,通过对旅游者在目的地消费行为的全面参与式观察调查,对旅游目的地经济地租结构进行了定量研究。研究表明:中国旅游生产空间体系存在明显失衡的经济地租结构;购物、游览空间经济地租明显过高;住宿、餐饮及旅行空间经济地租过低,变异程度达2.48。其中,高额经济地租的产生源于利益集团的勾结或资源垄断;而过低经济地租的形成除受竞争和基础设施条件影响外,管理水平低、缺乏技术创新是主要原因。失衡的经济地租结构将对目的地旅游发展形成结构性制约,降低旅游者在目的地的整体消费效用水平,阻碍目的地的持续发展,需要政府和生产者采取各种措施加以调控。