地震散射波模拟成像在金属矿勘探中的应用

由于金属矿地质模型一般具有强非均匀性,造成金属矿地震勘探中采集到的信号杂乱,应用常规的反射地震处理技术难以获得可靠的成像效果.而基于惠更斯一菲涅尔原理的散射成像方法能充分利用地震信号中的全波场信息,例如反射波、绕射波、回转波、直达波、转换波等,它们都是散射波的一种表现形式,从而可以获得较好的成像效果.结合中国东部典型铜矿-铜陵冬瓜山铜矿与中国西部典型锡矿-云南个旧锡矿的地质模型,我们模拟了散射波地震记录,并通过散射成像方法获得了高质量的偏移结果,从数值模拟角度证明了散射成像在金属矿地震勘探中具有较好的应用前景.     

Cloud contribution to the daily and annual radiation budget in a mountainous valley

An automated-ventilated radiation station has been set up in a mountainous valley at the Logan Airport in northern Utah, USA, since mid-1995, to evaluate the daily and annual radiation budget components, and develop an algorithm to study cloudiness and its contribution to the daily and annual radiation. This radiation station (composed of pyranometers, pyrgeometers and a net radiometer) provides continuous measurements of downward and upward shortwave, longwave and net radiation throughout the year. The surface temperature and pressure, the 2-m air temperature and humidity, precipitation, and wind at this station were also measured. A heated rain gauge provided precipitation information. Using air temperature and moisture and measured downward longwave (atmospheric) radiation, appropriate formula (among four approaches) was chosen for computation of cloudless-skies atmospheric emissivity. Considering the additional longwave radiation during the cloudy skies coming from the cloud in the waveband which the gaseous emission lacks (from 8–13 μm), an algorithm was developed which provides continuous 20-min cloud information (cloud base height, cloud base temperature, percent of skies covered by cloud, and cloud contribution to the radiation budget) over the area during day and night. On the partly-cloudy day of 3 February, 2003, for instance, cloud contributed 1.34 MJ m^− 2 d^− 1 out of 26.92 MJ m^− 2 d^− 1 to the daily atmospheric radiation. On the overcast day of 18 December, 2003, this contribution was 5.77 MJ m^− 2 d^− 1 out of 29.38 MJ m^− 2 d^− 1. The same contribution for the year 2003 amounted to 402.85 MJ m^− 2 y^− 1 out of 9976.08 MJ m^− 2 y^− 1. Observations (fog which yielded a zero cloud base height and satellite cloud imaging data) throughout the year confirmed the validity of the computed data. The nearby Bowen ratio station provided the downward radiation and net radiation data. If necessary, these data could be substituted for the missing data at the radiation station. While the automated surface observing systems (ASOS) ceilometer at the Logan airport provides only the overhead cloud information, the proposed algorithm provides this information over the valley. The proposed algorithm is a promising approach for evaluation of the cloud base temperature, cloud base height, percent of skies covered by cloud, and cloud contribution to the daily and annual radiation budget at local and regional scales.     

改进的时空数据基态修正方法

分析已有基于基态修正模型的5种数据存储方式,在此基础上提出多基态多级差文件修正方法、多基态单级差文件修正方法.与已有方法相比,提出的两种方法具有节省存储空间,历史数据恢复快而且不受历史久远影响的特点.多基态多级差文件修正方法与多基态单级差文件修正方法相比没有增加存储空间,但提高了数据恢复速度.讨论基态距阈值的确定方法,认为基态距阈值与时空数据库每次更新的目标数相关,更新目标数大时基态距阈值较小,目标数小时基态距阈值相对较大.     

国酒基地内矿业开发引发的地质环境问题及其对策

本文论述了国酒基地内矿产开发的主要形式,分布特征。矿产开采所引发的环境地质问题,并对其矿业开发提出相应的防治对策。     

福建浦城毛洋头铀矿床地质特征与找矿前景

浦城毛洋头铀矿床产于福罗山—大坑火山盆地内,盆地基底为上元古界麻源群大金山组变质岩系和燕山早期高溪复式花岗岩体。受断裂控制,矿体形态复杂,矿体群带具有向主干断裂侧伏,同时又向火山通道中心侧伏的"双侧伏"特点。中酸-酸性火山岩是有利的铀源层,构造产状变异部位、不同岩性接触界面,为铀成矿的有利富集地段。     

南方CORS系统在数字化测图中的应用

随着RTK技术在数字化测图方面的应用日益广泛,但对地形复杂测区,普通RTK技术常遇到诸多问题,造成作业效率低下。而CORS系统中的网络RTK技术是GPS-RTK技术进一步延伸,采用网络通讯大大延伸了RTK的作业半径,提高了定位精度和可靠性,以工程项目为例,详细介绍了网络RTK技术在数字化测绘中的应用。     

专题地图智能化快速规格设计模式研究

根据规格设计流程,阐述了专题地图智能化快速规格设计框架体系的总体思路,详细描述了地图投影知识库关键功能模块的内容和智能化选取机制,比较和分析两种模式流程中的关键环节,得出智能化快速规格设计模式具有高智能、高精度、整体设计速度快的结论。     

国家基础航空摄影项目中的IMU-DGPS技术方案设计

以乌拉盖测区为例,介绍了IMU-DGPS技术方案的设计过程,并详细讨论了地面基站、检校场、地标点和精度验证区的布设方案,并对其中需要注意的地方进行了总结。     

振冲置换法加固泵房软土地基技术的应用

以10座地泵房、882根碎石桩挤密软土地基处理为例,总结振冲置换法处理我国西部软土地基的具体施工工艺和施工质量控制.从效益上分析,经这种方法处理后的软粘土地基,承载力提高了3倍.在设计要求承载力不超过200 kPa的地基结构,采用振冲置换法比较经济.与预制混凝土桩基础相比,可节省工程费用60%左右.这种技术在经济欠发达的西北部地区极有推广应用价值.     

数字城市的建设与加快振兴东北老工业基地

在党中央、国务院提出调整、改造和振兴东北老工业基地的良好氛围中,东北地区的各行各业都围绕着这个中心来展望未来本行业的发展方向,以“数字城市”的建设为基础,通过促进城市的信息化建设,为老工业基地的改造与振兴提供更加便利的条件。