日本“第六次防灾科学技术研究联络会”开会情况

据日本《科学新闻》1981年3月13日报道,由日本科学技术厅主持的日本第六次防灾科学技术研究联络会议,最近在京港区的都道府县会馆召开。这次会议的中心议题是地震防灾和强震观测。东京大学名誉教授冈本舜三和东京大学地震研究所教授大沢胖,分别以《地震防灾和强震观测的意义》、《强震观测的国际合作》为题作了报告。高密度强震观测就地震来说,今后日本应走防灾和观测相结合的道路。冈本教授对此讲了如下看法。     

日本强震观测的历程

前言 (强震观测事业的历史 )1 955年 1月 3 1日 ,科学技术厅资源调查委员会向内阁总理大臣提交“关于强震测定计划的建议”,并以此为契机开始了强震观测。为了使建议从组织上得到落实 ,1 956年 1 2月在东京大学地震研究所设置了强震测定委员会。1 958年 1 1月 ,资源调查委员会又向科学厅长官提出了促进观测计划实施的请求。1 964年 1 1月 1 7日 ,日本学术会议向内阁总理大臣提交的“加强抗震工程研究的报告”中提出 :希望增设强震计并充分利用所获取的记录资料。 1 965年在东京大学地震研究所设置了强震观测中心 ,经费由国家财政拨款。 1 96…     

使用双频谱的比值方法推测岩手山正下方的Q_S~(-1)值

前言1998年 9月 3日 16时 5 6分 ,在岩手县北部发生了 6 .1级 (日本气象厅所发布的震级 )地震。从这次地震的强震仪的记录可以看出 ,通过岩手山正下方的地震波受到强烈衰减。在本篇论文中 ,采用多个观测点 ,多个地震观测记录 ,去掉震源和观测点正下方的震动特性 ,只提取出射线路径上的传输特性 ,把这样的双频谱比的方法 (Matsuzawa et al.,19 89)运用到强震动记录 ,来推测岩手山正下方的 Q-1 S 值。1　在岩手县周围观测的地震记录图 1所示的是科学技术厅防灾科学技术研究所的 K-NET的观测点分布图 ,图 2所示的是由图 1得到的这次地震的强…     

新疆钻孔应变异常与强震活动

在新疆钻孔应变18年的观测期间，发生了6级以上强震17组(次)，其中7级以上地震5次，8级以上地震1次。钻孔应变资料在64％强震前记录到了异常变化。其中属于天山和塔里木地块周边的15例强震中，在儿例地震前钻孔应变资料出现了异常，占全部强震的73％。利用钻孔应变资料正确预报的地震数仅4例，占全部强震的23％，占天山及塔里木地块周边地震数的26％。在这些强震中距离台站250km范围以内发生的地震有7例，正确预报的有4例，占57％。     

1990年强震观测工作会议在无锡召开

强震观测工作是地震工作的一个重要组成部分。为了交流和俭查1989年强震观测的工作情况,加强今年重点地震监视区的工作,进一步完善强震观测的有关管理制度,国家地震局震害防御司于1990年5月6日至5月9日在江苏省无锡地震科技交流培训中心召开了强震观测工作会议。江苏省地震局,四川省地震局,新疆地震局、广东省地震局、云南省地震局、兰州地震研究所、武汉地震研究所、地球物理所、国家地震局分析预报中心和工程力学研究所     

中国大陆及其邻区地震幕的划分及其时间结构的某些特征

依据地震活动的层次性和有序性,分析了中国大陆及其邻区7级以上强震的时间结构,研究了地震幕内强震成组的规则性。给出了地震活动幕的三条判据,即高震级(Ma≥(7)1/2)、短时段(△t<6年)和低k值(K<10)。并由平静幕强震组的参数值判定其后地震活动幕首发强震的时间。     

工程强震观测仪器触发装置的抗干扰设计

工程强震观测是地震科学研究的重要课题之一,而触发式记录则是强地震与工程强震记录的主要方式.利用地震信号(位移,速度或加速度)本身作为触发信号而设计的各类强震观测仪器(PDR-1,2;DR-100,200;GQ-Ⅱ,Ⅲ;QZ-2A 等)所面临的主要困难是如何减小误触与漏触概率,即提高触发器的抗干扰能力,本文对利用地震信号的不同特征参量作为触发信号时的误触与漏触概率作了对比分析,提出了幅度特征--窗口比较器触发电路的设计,在GQ-Ⅱ及 QZ-2A 型仪器的现场使用和抗干扰实验中取得了预期结果.误触与漏触概率降低到1%以下,抗干扰能力明显提高.      

前言

20 0 3年 1 2月 ,国家科技部批准建设地震动力学国家重点实验室 ,实验室依托单位为中国地震局地质研究所。中国地震局地质研究所所长张培震研究员为实验室主任 ,中国科学院院士马瑾研究员为学术委员会主任。地震动力学国家重点实验室是以原构造物理开放实验室、新构造年代学开放实验室等为基础组建的。实验室以构造物理实验和模拟技术、活动构造与年代学技术、空间对地观测技术、流动地震台阵技术等为依托 ,以地震动力学 (地震机理、动力学过程等 )与强震预测为主题 ,以现今构造变形图像与强震危险性、岩石圈三维精细结构与孕震环境、活动构造习性与强震发生规律、构造变形机制与强震发生机理为主要研究方向。地震动力学国家重点实验室目前设有构造物理实验室、新构造年代学实验室、现代地壳运动研究中心、流动台阵地震学研究中心等 4个研究单元。现有工作人员 35人 ,其中研究员 1 4人 (包括中国科学院院士 2人 ) ,副研究员和高级工程师 1 1人。实验室通过依托单位接受地质学博士后研究人员 ,招收固体地球物理学和构造地质学博士和硕士研究生 ,现有在站博士后、在读博士和硕士研究生 30余人。地震动力学国家重点实验室在构造物理学方面拥有构造变     

K台网简介

前言Ｋ－ＮＥＴ（ＫｙｏｓｈｉｎＮｅｔ）是１９９５年兵库县南部地震后,科学技术厅防灾科学技术研究所在全国１０００个地点（现为１００１个地点）布设的强震仪台网。由于是在全日本以约２５ｋｍ的间隔布设同一规格的加速度型强震仪,故能进行非常均匀的观测。该台网是...     

晋冀蒙三省交界地区中强地震前地震活动特征

晋、冀、蒙三省交界地区(以下简称“北三省”地区)地质构造复杂,具有深大断裂,历史上曾发生过1次7级以上地震和8次6级以上地震。自有台网观测以来,已有丰富的地震资料。近些年来,一直被定为重点监视区,因此研究该区强震前地震活动特征对于该区的地震监视预报工作是有意义的。     

Contribution to the knowledge of the magmatic evolution by the study of the variation of the coefficient of viscosity

The determination of the coefficient of viscosity of eruptive products gives useful elements to the knowledge of possible variations of composition and physical conditions of the magmas.     

Pictorial Series of the Manifestations of the Dynamics of the Earth

Studia Geophysica et Geodaetica -     

Evolution of the Source of the Active Region of the Sun

Geomagnetism and Aeronomy - The magnetic evolution of the active region of the Sun at the level of the photosphere has been studied. Magnetic synoptic maps of the 2007 Kitt Peak Observatory were...     

Magnetic stratigraphy of the Ordovician in the lower reach of the Kotuy River: the age of the Bysy-Yuryakh stratum and the rate of geomagnetic reversals on the eve of the superchron

Until recently, the existing data prevented the geophysicists from accurately dating the Bysy-Yuryakh stratum, which outcrops in the middle reach of the Kotuy River, constraining the time of its formation to a wide interval from the end of the Late Cambrian to the beginning of the Silurian. The obtained paleomagnetic data unambiguously correlate the Bysy-Yuryakh stratum to the Nyaian regional stage and constrain its formation, at least a considerable part of it, by the Tremadocian. This result perfectly agrees with the data on the Bysy-Yuryakh conodonts studied in this work and yields a spectacular example of the successful application of paleomagnetic studies in solving important tasks of stratigraphy and, correspondingly, petroleum geology. Within the Bysy-Yuryakh stratum, we revealed a large normal-polarity interval corresponding to the long (>1 Ma) period when the geomagnetic reversals were absent. This result, in combination with the data for the Tremadocian and Middle–Upper Cambrian sequences of the other regions, indicates that (1) the rate of occurrence of the geomagnetic reversals on the eve of the Ordovician Moyero superchron of reversed polarity was at most one reversal per Ma; (2) the superchron does not switch on instantaneously but is preceded by a certain gradual change in the operation conditions of the dynamo mechanism which, inter alia, manifests itself by the reduction of the frequency of geomagnetic reversals with the approach of the superchron. This finding supports the views according to which a process preparing the establishment of the superchrons takes place at the core–mantle boundary.     

The effect of the pollution of the ground layer of the atmosphere on the albedo

Summary A simple model is proposed suitable for studying the effect of the ground layer of the atmosphere, polluted by aerosol, on the albedo. This model is founded on solving the equation of transfer of radiative energy. The numerical results are discussed, particular attention being paid to the analysis of errors due to neglecting the multiple reflection of solar radiation on the aerosol particles. A method which would also include the multiple reflection is proposed, and the conditions under which the presence of the aerosol is responsible for an increase or decrease of the solar radiation balance on the Earth's surface, are analysed.     

On the solution of the reverse problem of geodesics with the help of the chord

Резюме Дается вывод формул для вычислений длины хорды, длины и азимутов нормаляных сечений и длины геодезической линии эллипсоида. Применяются тригонометрические функции данных величин и постоянные принятого ргфгргнц-эллипсоида, что является целесообразным при использовании вычислителQjных машин, особенно автоматов. Рабочие формулы рекомендуются в форме (8–11).

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Dedicated to Professor František Fiala on His 85th Birthday

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Address: Veveři 95, Brno.     

On the determination of the non-linearity of the gravimeter scale

Summary The results of two different methods of the determination of the non-linearity of the gravimeter scale are compared; the economy is discussed as well.     

Influence of the topography of the surface of the Earth on vertical sounding of the temperature profile

Atmospheric temperature and humidity fields as well as information on other meteorological parameters are nowadays retrieved from radiance measurements recorded by operational meteorological satellites. Up to now, the inversion procedures used only take into account crude information on the topography of the Earth’s surface. However, the applied radiative transfer codes have to consider the Earth’s surface as the lower boundary of the atmospheric model and, therefore, need a more precise mean elevation and a classification of the roughness of the Earth’s surface. The influence of the topography of the Earth surface on retrieved temperature profiles is studied by using a physico-statistical inversion method. An objective analysis is made of the more precise mean elevation and derivation of roughness parameters using a new high-resolution digital elevation model (DEM) with a resolution of 500 m×500 m. By means of a geomorphological process and a newly developed topography rejection test, areas with a high surface roughness are localized and singled out. The influence of topography on the retrieved temperature profiles is illustrated by case studies. Changes are found predominantly in areas with a high variation of topography. Using the new high-resolution DEM and the topography rejection test, the geographical position of the calculated temperature profiles tends to be shifted towards areas with a small vertical variation of topography. The mean elevation determined by the new elevation model better characterizes the area observed. Hence, the temperature profiles can be calculated down to lower atmospheric levels. Furthermore, a guess profile better describing the atmospheric situation is selected by the more precise elevation. In addition, the temperature profiles obtained near the coast are improved considerably by the more precise determination of the surface property ‘sea’ and ‘land,’ respectively. Integration of an independent physical information such as topography leads, on average, to a slight improvement of the results of the physico-statistical inversion procedure. In some cases, however, significant improvements have been achieved regarding the desired accuracy of temperature profiles of the order of 1 K. In future, the spatial resolution of new high-resolution sounding instrumentation on the next generation of operational meteorological satellites will be increased. To exploit the resolving power of this new instrumentation, the different variation of the topography of the Earth surface, especially in regions with a high variation of topography, can be taken into account more precisely by using a high-resolution DEM.     

On the gravimetric undulations of the geoid and the deflections of the vertical

Summary The author mentions the aims of the World-wide gravity project he established in the Ohio State University in Columbus, in 1950. He outlines the practical procedure of the gravimetric computations of the undulationsN and the vertical deflection components and and emphasizes that only by the global international cooperation and additional gravity observations at sea carried out during the last decade it has been possible to gather to Columbus the needed gravity material. Since there exist still large gravimetrically unsurveyed areas it is of vital significance to study what gravity anomalies are best to be used for these regions. The given figures concerning the accuracy of theN, and , estimated theoretically and obtained in practice, indicate that in the gravimetrically well surveyed parts of the world like in Europe and the United States we can get gravimetrically on basis of existing gravity material theN-values with accuracy of about 5–10 meters, and and with the accuracy of about 1. The geoid undulationsN are already computed in Columbus for more than 6000 points of the northern hemisphere. The sample maps show the interesting geoid of Europe and vicinity between the latitudes 60° and 30° and longitude 5° W and 30° E, drafted on basis of more than 1000N-values computed at the corners of 1°×1° squares. It is interesting to realize that the geoid undulations in all this area are positive, the extreme values being between 40 and 50 meters. The geophysical significance of the geoid maps of this kind is pointed out.