Study on shallow structural features Changbaishan Tianchi volcanic region

A seismic survey by 10 shallow profiles and 6 ultra-shallow profiles was performed in Changbaishan Tianchi volcanic region in 2002. The result shows that there are three （in some areas as many as seven） stable interfaces in the survey region, but no reflection phases are found in depths greater than 500 m. The number of interfaces in the southwestern part is obviously greater than in the northwestern part of Tianchi volcano, which suggests that the faults in the southwest have a stronger controlling power over the flow direction of volcano-spewed lava as compared with those in the northwest. Six shallow faults exist in the survey region. The shallow faults are nearly vertical graben-like faults and are mostly distributed on the southwest of Tianchi crater, indicating that volcanic activities in the southwest are stronger than in the northwest. On this ground, it could be further deduced that the NE-trending major fault of Tianchi volcano （ the Liudaogou-Tianchi-Zengfengshan fault） is more active than the NW-trending Baishanzhen-Tianchi-Jince fault.     

亚洲地震委员会第四次学术大会于2002年11月在尼泊尔加德满都举行

亚洲地震委员会（ASC）第四次学术大会暨地震学、地震危险性评估和地震风险管理学术讨论会于2002年11月24－26日在尼泊尔加德满都举行。来自亚洲、大洋洲、美洲和欧洲的22个国家的近200名专家出席了会议，会议共收到约110篇研究报告。文章介绍了大会、学术交流和ASC工作会议等情况。     

郑州和永城地区地基土的物理力学性质比较分析

利用数理统计方法，对河南省郑州地区和永城地区地基土的物理力学性质进行了比较分析，找出它们的联系与差异，其各类土的各种特性指标基本正确反映了两个地区沉积差异情况下的工程特性，对郑州地区和永城地区岩土工程勘察、设计、施工有一定的参考价值。     

The Crust-mantle Structure and Seismic Risk in Tangyin Graben and Its Adjacent Area

1-D and 2-D calculation and interpretation are carried out with the DSS data from the western section of Heze-Changzhi profile and the southern section of Zhengzhou-Jinan profile. 2-D velocity structure is determined in Tangyin graben and its adjacent area. The result shows that velocity structure of the crust and upper mantle is obviously different in vertical and lateral directions. Crustal thickness varies apparently in this area, and there are local low velocity blocks in the interior crust. The swelling M-discontinuity corresponds to Tangyin graben and Moho depth at the highest swelling position is 31 km. Toward the east, its depth gradually increases to 32 km in Xunxian swelling; toward the west, M-discontinuity becomes a steep zone at the piedmont uplift of Taihang Mountain and reaches 40 km at depth near Changzhi. Through analyzing the relationship between historical earthquakes and deep structure in North China, we infer that seismic risk exists in Tangyin graben and its adjacent area.     

The movement age of hidden fault and analysis on width of its effect zone from shallow seismic sounding and drilling data

Introduction Artificial seismic sounding is a geophysical exploration technique developed in prospectingfor oil and gas and other mineral resources and consists of reflection wave and refraction waveexploration methods. With rapid development of computer techniques and sounding instruments,the reflection wave method became a high-resolution imagery technique for underground struc-tures and is widespreadly used in detection of underground caves and in engineering exploration.In previous se…     

东秦岭古生代古生物区与古地理变迁

本文根据对东秦岭古生代各纪古生物区的分析，指出在北美岭褶皱带，二郎坪海槽寒武纪放射虫和微浮游植物属华南区，奥陶纪头足类，腹足类、珊瑚为华北区，早志留世珊瑚为华南区，柿树园海槽中泥盆世至二叠纪孢子主要见于华南区，干江河海槽泥盆纪珊瑚，海百合为华南区。在南秦岭褶皱带，浙川陆棚寒武纪三叶虫有华北区和华南区的分子，奥陶纪牙形石、头足类由华南区变为华北区，晚奥陶世腕足类、三叶虫、珊瑚为华北区，而早志留世笔石，晚泥盆世珊瑚，腕足类和Ting、古植物以及早石炭世珊瑚和Ting均为华南区，南湾海槽泥盆纪孢子为华南区。在此基础上探讨了东秦岭古生代古地理变迁过程。     

基于ORACLE数据库的遥感影像存储技术

遥感影像的存储与管理是当前急待解决的问题。文中基于ORACLE数据库中典型数据类型的分析，提出并实现了遥感影像存储的3种不同途径和方法。     

机载SAR图像定向参数的F．LDT解法

从SAR图像的F.Leberl构像模型出发，推导了成像载体匀速运动条件下的SAR图像定向参数的直接变找（Direct Transformation for F.Leberl Model。F.LDT）解法。通过比较F.LDT解法与F.Leberl构像方程线性代迭代解法的实验结果，得出结论：F.LDT解法可以满足精度要求，且无需初值，不需迭代，计算过程简单，避免了线性化迭代方法不收敛的情况。最后对影响F.LDT解法精度的因素进行了分析。     

WebGIS可视化创作系统研究

主要针对地理信息系统的地理要素网络3维可视化实现，对WebGIS可视化创作系统进行研究，并分析了其构成及工作原理，为制定一套完善的WebGIS3维可视化创作系统的标准提供了有益的借鉴价值。     

张北地震前Morishita播散指数空间演化特征

用Morishita播散指数研究了 1998年 1月 10日河北省张北M6 2地震的发展过程。发现从震前 3年半开始 ,Morishita播散指数异常空间演化经历了两次过程。即 1994年 8月至 1996年 1月 ,在震中周围 (2°× 2°内 )从无异常 ,到震中一侧出现异常 ,发展到异常向震中集中的过程。 1996年 2月至 1998年 1月 9日 ,又经历了无异常 ,到震中一侧出现异常 ,异常向震中发展 ,最后形成包围震中的态势 ,直到发震。Morishita播散指数的空间异常演化特征 ,有可能揭示张北地震的孕震阶段性发展过程 ,并为历史上无强震、且地表构造发育不明显的地区的破坏性地震的预测 ,提供了新思路