20年来我国地震观测技术的进展和近期发展浅见

众所周知,地震观测技术是地震学研究最重要的基础。近２０年来,随着高新技术的不断发展,促使了地震观测方法的更新,地震观测设备的换代和地震数据处理技术的创新,使当代地震观测技术发生了革命性的变化,推进了地震学研究的发展,获得了一批令人注目的科研成果。值此世纪之交,回顾近２０年来我国地震观测技术的发展历程和对下个世纪的近期展望,既很必要也颇具意义。８０年代中期,国家地震局采用７６８工程独立开发研制完成的以计算机系统为核心设备的地震观测系统,在全国建成了２０余个不同孔径的模拟遥测地震台网,使我国的地震观…     

768自动换纸地震记录器笔放系统检测装置

７６８自动换纸地震记录器笔放系统检测装置王玲（中国北京１０００８１国家地震局地球物理研究所）北京遥测地震台网是大型区域性地震台网，主要任务是取得连续、可靠、准确的地震观测资料。以监测华北地区的地震活动，速报国内外大地震，为地震预报及地震科学研究提供第...     

地震前兆和地震观测的数字化传输

地震前兆和地震观测的数字化传输１．引言地震观测在经历了沙盘记录、薰烟记录、电子放大等模拟记录阶段后，在１９世纪七十年代初，国外已不断地对地震观测数字化传输进行研究与应用。国内在“７６８”工程建设中，作为全国六大区域台网之一的兰州地震遥测台网，也受命进...     

新安江地震台数字化改造设计

新安江地震台根据“中国数字地震观测网络”总体设计和“浙江省数字地震观测网络”建设的要求,对原有的观测楼、观测山洞进行数字化升级改造[1]。原观测楼拆除,新建440m2观测楼,并在原有设备基础上新增甚宽带地震计KS-2000和强震计PS-23。改造设计严格按照《地震及前兆数字化地震观测规范》的要求。     

世纪之交的北京遥测地震台网

回顾北京遥测地震台网走过的３０年历程,面对长城脚下的世纪钟,我们将和北京遥测地震台网一同跨入新世纪。为了完成我国防震减灾任务的总目标,必须加强地震观测。地震观测是开展地震学和地震预报研究工作的基础。我国地震观测的历史开始于单台观测,后来发展为地方地震台网,区域地震台网,地震台网联网和数字化地震台网。对于地震观测来说,地震速报和地震预报今后仍然是相当艰巨的任务。１　北京遥测地震台网的诞生（１９６６年４月）我国现代地震观测始于１９世纪末。当时建立了２０多处地震台站,其地震的观测方法大多是有人职守的单…     

GS-15型重力仪记录比值的标定

昆明台对 GS-15型重力仪在自动记录时测定记录比值的方法有二个步骤:第一,用拉读数弹簧的方法求出仪器输出的电讯号与重力值的关系;第二,输入一个直流电讯号给记录器,求出记录器上的单位长度与电讯号的关系。再通过这二个关系,求得记录器上单位长度所表示的重力值——记录比值。 记录比值标定的要求 地震观测系统中,GS-15型重力仪所观测到的资料,一是利用重力值随时间的变化来研究它与地震的关系,二是利用来研究重力固体     

西宁台DD－1地震记录仪的改造

介绍了西宁台ＤＤ－１地震仪的改造工作，并讨论了改造后的ＤＤ－１记录器的工作状况，得出：改造后的ＤＤ－１地震记录器基本上解决了原记录器的缺点，使记录性能及记录效果有了明显的提高，其改造工作是成功的。     

大连地震台数字与模拟记录测定震级的对比研究

大连地震台在“九五”计划后期安装了宽频带数字化地震观测仪器。2000年10月,经专家组验收合格并投入正常运转。现已取得近1年的观测资料与7个月的正式数字仪器地震观测报告。     

丹江口水库区地震观测30年

介绍了近３０年来丹江口水库区地震观测台网完整记录到的蓄水过程的水库诱发地震序列，回顾了地震观测台网的建设和调整过程，阐明了所取得的观测成果和存在的问题。最后讨论了如何完善地震观测台网等问题。     

20年数字地震观测技术发展

<正>"八五"期间,中国提出发展自己的数字地震观测系统,比西方落后近20年,形成的数字地震观测系统分为台网、流动台网和台站3部分。区域台网和流动台网的试验系统分别在北京遥测地震台网和江苏省地震局进行试验,发现并提出了一系列问题。"九五"期间,对改进后的自主研发数字地震现测系统在部分区域台网推幵,改进、推广经历了一段艰辛的历程:经过设备与软件改进,     

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 -     

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.     

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...     

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).

---

---

Dedicated to Professor František Fiala on His 85th Birthday

---

Address: Veveři 95, Brno.     

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.     

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 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.     

On the maintenance of the axisymmetric part of the flow in the atmosphere

Summary The maintenance of the axisymmetric component of the flow in the atmosphere is investigated by means of a steady-state, quasi-geostrophic formulation of the meteorological equations. It is shown that the meridional variations in the time-averaged axisymmetric variables can be expressed as the sum of three contributions, one being due to the eddy heat transport, another to the eddy momentum transport, and a third to the convective-radiative equilibrium temperature which enters the problem through the specification of a Newtonian form of diabatic heating. The contributions by the large scale eddies are evaluated through the use of observed values for the eddy heat and momentum transports.The contributions from each of the three forcing mechanisms to the temperature and zonal wind fields are invstigated individually and found to be of about equal importance. The sum of the three contributions are also presented for the temperature, the zonal wind, the stream function associated with the mean meridional circulation and the corresponding vertical motion. Although the results fail to reproduce the main observed features of the lower stratosphere, they are found to be in good agreement with observations in the middle latitude troposphere. At any pressure level, for example, the computed mean zonal wind has a jet-like profile and the axis of the jet is found to slope to the south with height, as observed in the atmosphere.Based in part on a thesis submitted by the first author as partial fulfillment of the requirements for the Ph.D. degree at the University of Michigan. — Publication No. 194 from the Department of Meteorology and Oceanography, The University of Michigan.