2002年玉门5.9级地震余震监测和定位研究

介绍了玉门5.9级地震后临时台网监测情况,利用台网资料进行了余震定位和误差分析研究。     

Imaging the heterogeneity of mineral surface reactivity using Ag(I) and synchrotron X-ray microscopy

Microscopic-scale imaging of reduced zones on the surfaces of minerals can be achieved by reaction with dilute Ag(I) solutions and subsequent analysis using synchrotron X-ray microscopy (XRM) above the Ag K-edge (25.5 keV). The principal reductant is Fe(II), but other reductants such as sulfide may contribute. Reduced zones may exist instrinsically, as in the structure of biotite and augite, or may be generated by reaction with chemical agents such as dithionite or treatment with sulfate-reducing bacteria (SRB). We demonstrate the method on flakes of specular hematite and biotite, as well as on thin sections of different rocks (arfvedsonitic granite, oolitic hematite, diabase, and quartz conglomerate) treated with SRB, and discuss possible artifacts that can occur. To our knowledge, this is the only microscopic technique that can image Fe(II) zones on the surface of an Fe-bearing mineral with monolayer sensitivity.     

玉门市地震宣传和应急工作

0前言甘肃省玉门市位于河西走廊西端,处在阿尔金山断裂带和祁连山北缘断裂带的交汇地带,境内地质构造复杂,历史上曾经发生过多次破坏性地震,其中包括产生广泛影响的1932年昌马7.6级大地震和2002年青西5.9级地震,近年来被中国地震局和省地震局确定为地震注意监视区。面对严峻的地震环境和震情趋势,玉门市委、市政府一直十分重视防震减灾工作,坚持以建立健全防震减灾“三大工作体系”为重点,加强领导,精心部署,狠抓落实,在防震减灾宣传和地震应急工作方面积累了一定的经验。1努力提高防震减灾宣传工作水平1.1科学规划,明确防震减灾宣传工作目…     

辽宁兴城小盖州地区元古宙火山岩及扇－三角洲沉积

小盖州剖面元古宙火山岩具有安山岩岩石成分，由熔结角砾岩、熔岩角砾岩及熔岩组成。安山岩与围岩的接触性质表明二者形成于同一地质时期，与蓟县剖面相较，该火山活动应与大红峪组火山活动时期相当。该剖面上的砾岩曾被作为底砾岩并标示“兴城运动”的存在。本次研究表明，该底砾岩实际为一扇－三角洲体系的顶部沉积，它不能作为区域性地壳运动的标志。本文将砾岩之上地层划归高于庄组，而砾岩本身及其下部含安山岩的地层归入大红峪组。     

陕西洛南─古城一带的震旦系

据对陕西洛南─古城一带所出露的一套钙质砾岩的沉积特征及其与国内相应层位的对比研究．提出这套砾岩应属于震旦系．     

河西走廊盆地西段玉门断裂晚新生代的活动特征

玉门断裂中段地表地貌陡坎明显,主断裂直接出露地表,使前新生代地层或早新生代地层与晚新生代松散沉积物呈断裂接触,说明玉门断裂中段形成早、活动时间长、位移幅度大,从而在冰沟口一带形成宽度超过200m的巨大破碎带。玉门断裂西段新构造活动表现的最大特点是地表较少见及主断裂的出露,以隐伏断裂为主。在地表常见有由新近系地层组成的不对称褶皱构造,属于与逆冲断裂密切相关的、也是正在变形的“活动背斜”。这说明玉门活动断裂西段形成时间较晚、活动时间短、活动位移幅度比较小。玉门断裂的活动性质以粘滑变形为主,次为蠕滑变形。玉门断裂是全新世活动断裂,最近2次新构造活动发生在距今7.4ka和3.2ka的全新世中期和晚期。该断裂也是现代发震断裂,,其西端深部的扩展破裂引发2002年的5.9级玉门地震。     

2002年12月17日玉门ML4.5地震的强震仪多条记录资料分析

对2002年12月17日玉门ML4．5地震近场多道强震仪的加速度记录进行了分析处理，校正了仪器响应和基线，计算了速度和位移时程曲线及各种谱值，并对记录特点做了分析。     

甘肃近期几次中强地震震源机制解

12002年12月14日玉门MS5.9地震发震时间:21∶27′27″;经纬度:39.8°N,97.3°E;深度:33km;震级:MS5.9。收集了全省及邻近省份共同31个台站初动后作出震源机制解(表1,图1)。表1　玉门MS5.9地震震源参数节面A节面BP轴T轴N轴矛盾比/%走向倾角滑动角走向倾角滑动角方位角仰角方位角仰角方位角仰角147°26°35°24°75°111°277°27°140°55°18°21°0.09722003年10月25日民乐-山丹MS6.1地震发震时间:20∶41′36.4″;经纬度:38.33°N,100.95°E;深度:12km;震级:MS6.1。收集了全省21个台站初动后作出震源机制解(表2,图2)。表2　民乐-山…     

Experimental Study of the Main Influencing Factors in Mechanical Properties of Conglomerate

In recent years, with the success of exploration and development of conglomerate reservoirs in Mahu Depression, Junggar Basin, China, it is urgent to study the mechanical properties and its influencing factors of conglomerate which is considered as a new oil and gas reservoir. Based on the investigations of petrologic characteristics, heterogeneity and mechanical properties of conglomerate in Baikouquan formation, the content and geometric characteristics of gravel in conglomerate, the main factors in heterogeneity and the mechanical behavior in the triaxial compression experiment of conglomerate are analyzed in this paper. The results show that the size and content of gravel in conglomerate varies greatly, and conglomerate has strong heterogeneity under the influence of gravel content and size. An analysis of mechanical properties of conglomerate shows that conglomerate is characterized by plasticity. Besides, the sphericity is negatively correlated to the gravel content, while the heterogeneity increases with the increase of conglomerate plasticity. Due to the existence of heterogeneous gravel, local stress may concentrate in conglomerate when the stress is loaded. Consequently, a large number of micro-cracks appear at the edge of gravel, demonstrating the strong plasticity of conglomerate. This paper is of referential significance to the study of rock mechanical properties and the evaluation of engineering properties in conglomerate development.     

2002年12月14日甘肃玉门5.9级强震余震记录

介绍了2002年12月14日21时27分甘肃玉门Ms 5.9破坏性地震后,在流动观测中所获取的强余震记录资料,并对其进行了地震波动力学特性的初步分析.