我国海洋地球物理探测技术发展现状及展望

海洋地球物理场是一个四维的动态复杂变化系统,涉及多物理场、多界面和多尺度问题,受内外因素的共同制约.基于海洋地球物理场特征,海洋地球物理探测是揭示地球内部构造与性质的重要技术手段.通过回顾国内外海洋科学研究历史以及海洋地球物理探测技术的发展历程,对我国海洋地球物理探测技术发展进行了分析,现今的技术发展受科技进步驱动,反映国家与时代发展的需求.探讨了技术发展与需求之间的关系,依据各种地球物理探测手段及其探测平台的特点,提出了以下技术展望:优化传统的海洋地球物理勘探技术;加速并完善多样式探测平台的建设和科学载荷的研究;构建"空-天-海-潜"海洋地球物理立体探测体系;海洋地球物理探测技术与"大数据"和"人工智能"等技术深度融合.     

国家地球物理基础设施：意义和任务

本文简要阐述了国家层面的基础设施对地球物理学科发展的重要性，讨论了国家地球物理基础设施的建设和运行在当前时间的紧迫性.指出中国地球物理发展的三个主要任务：基础地球物理探测、基础地球物理检测、基础地球物理数据共享服务.国家层面的地球物理基础设施的建设能够为相关科研机构提供高科技含量的服务.     

苏联石油工业中地球物理勘探方法的发展情况

地球物理工作在石油工业中已获得了公认,并在普查和勘探油田的综合地质勘探工作中居于牢固而称职的地位.三十七年前,苏联就开始了第一次勘探地球物理工作,最初是用来研究库尔斯克磁力异常上的鉄矿床.1919年根据列宁的指示在库尔斯克地区开始了磁力测量.1925年在乌拉尔-恩巴油区开始了第一次用地球物理勘探石油的工作,旨在寻找盐丘构造.     

关于召开勘探地球物理北京(89)国际学术讨论会通知

中国地球物理学会、中国石油学会和中国地质学会联合发起组成的中国勘探地球物理联合会(UCEG)与美国勘探地球物理工作者协会(SEG)决定于1989年5月23日—27日在北京联合召开“勘探地球物理北京(89)国际学术讨论会”。 会议旨在为世界各国的勘探地球物理学家们提供讨论问题、交流经验的论坛,增进国际同行们的合     

新版教材——《地球物理测井方法与原理》出版

《地球物理测井方法与原理》是石油工业出版社出版的“高等院校石油天然气类规划教材”系列之一。可作为高等院校地球探测与信息技术专业本科生教学用书,并可供地质勘察和地球物理勘探等相关专业和学科的研究生以及现场从事地球物理测井的工程技术人员使用和参考。     

页岩气勘探开发中地球物理技术的应用

本文基于页岩气勘探开发新形势,对地球物理技术在我国页岩气勘探开发中的应用现状、问题和面临的挑战进行了分析.在页岩气的勘探开发过程中,地球物理技术发挥着在常规油气勘探开发中完全不同的作用,地球物理技术可为优化页岩气钻井及储层压裂改造部署提供重要技术支撑.本文还介绍了国外利用封闭应力指导水平井钻探、综合运用杨氏模量和水平应力差比进行页岩气工程"甜点"预测、运用得到的岩石力学属性进行相关分析指导压裂的一些成功范例;但是,在页岩气勘探开发中,地球物理技术还面临着各向异性、含气丰度预测、工程"甜点"预测等难点的挑战,针对这些难点,本文提出了发展适用于我国页岩气开发的特色地球物理技术的建议.     

勘探地球物理(89)国际讨论会在京召开

勘探地球物理(89)国际讨论会(BISEG—89)于1989年8月22日至26日在北京举行,此次大会是在三年前由中国地球物理学界的三位元老顾功叙、傅承义、翁文波先生发起,立即得到美国勘探地球物理协会(SEG)前主席R、J. Greaen、技术委员会主席Stanley B. Jones等的热情支持,经由中国勘探地球物理联合会(UCEG)和美国勘     

应用地球物理方法寻找隐伏矿床

在金属矿勘探的发展过程中，地球物理的重要作用逐渐崭露头角．随着地球物理认识的不断深化，特别是地球物理勘探方法、仪器设备以及资料处理的长足进步，使得其勘探能力迅速提高．在当前攻深找盲、寻找大矿的需求下，地球物理勘探不应将自己局限于具体矿床勘探的战术作用，虽然这方面的勘探能力有了很大发展，然而更重要的是地球物理勘探应该而且可能在找矿的宏观战略方面作出重大贡献．     

海试引发深水油气综合地球物理采集的几点思考

深水地球物理采集技术随着国际海洋油气勘探的不断升温,技术水平不断提高.本文结合我国的地球物理海试实践,提出深水油气综合地球物理采集的几点思考,地震采集参数的选择,重磁震采集过程的实时监控,总结海试过程深水地球物理采集的两方面进展,一是精确定位的长缆二维地震采集技术,二是高精度的重磁震联合质量监控的综合地球物理测量技术,为深水油气勘探提供采集技术保障.     

生物地球物理:地球物理方法在研究生物地球化学过程中的应用和发展

微生物广泛参与了其所处地质环境的物理和化学性质改造过程.监控微生物与地质介质之间相互作用的过程并了解其机制对近地面环境工程中土壤及地下水污染整治等实际应用有着至关重要的作用.地球物理勘测成像技术不仅能够在传统应用中测量和表征地表以下的物理特性变化,大量直接有效的证据表明这些方法还可以捕获孔隙介质中的生物地球化学变化的动态过程,包括监测微生物、微生物活动以及它们与矿物之间的相互作用.生物地球物理(Biogeophysics)作为勘探地球物理的一个新兴分支学科,包含了微生物学、生物地球科学以及地球物理勘测等多个学科,侧重于研究微生物与地质介质相互作用对地球物理场的影响.过去十几年在生物地球物理领域的研究充分表明和验证了地球物理勘测方法的独特优点(最小化侵入、时空连续及跨尺度运用),并为将传统勘测方法用于探索跨时间空间各尺度的地下生物地球化学动态过程提供了理论及实验依据.本篇综述将系统介绍生物地球物理学科的理论背景、发展和研究前沿.首先讨论微生物及其活动引起的孔隙介质中物理化学性质的变化.其次,将侧重于探讨微生物活动对包括地电法、电磁法、探地雷达以及地震法等不同地球物理场的响应.最后将讨论生物地球物理领域的机遇、挑战和潜在应用.     

On the synchronism in the events within the core and on the surface of the earth: the changes in the organic world and in the polarity of the geomagnetic field in the phanerozoic

The data on geomagnetic reversals are compared with the changes in the organic world and with the lower-mantle plumes. The times of the formation of plumes and the times of their appearance on the Earth’s surface relate to the intervals characterized by the different frequencies of geomagnetic reversals, i.e., there is no interrelation between the formation of plumes and the frequency of the changes in the geomagnetic field polarity. At the same time, a certain synchronism is observed between the frequency of the geomagnetic reversals and the boundaries of the biostratigraphic ages, i.e., the changes in the organic world in the long-period range. A hypothesis is proposed, which explains the change in the sign of the geomagnetic field by the combined effect of the irregular rotation of the internal core relative to the mantle and the changes in the slope angle of the axis of the Earth’s rotation, which, in turn, results in synchronous events on the Earth’s surface: the rates of changes in the organic world.     

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.     

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.     

太平洋中部地磁台11年周期变化的研究

综合APIA、HONOLULU、PAMATAI 3个地磁台三分量的11年周期变化的形态后,可定性地提出该变化源于内场。如内源为核幔边界的电涡流,则其中心点应位于3台之间。     

Comparison Between the Nutations of the Planet Mars and the Nutations of the Earth

The nutations of the planets Mars andEarth are investigated and compared. Alarge number of interior structureparameters are involved in the nutationcomputations. The comparison between the observations and the computationsprovides several constraints on these parmeters andtherefore allows a better understanding of the physics of the interior of theplanet. For the Earth, the high precision of the observations of the nutationshas led to a very good determination of interior properties of the planet. ForMars, observations of nutations are not yet available, and we review how theamplitude of the Martian nutations depends on the hypotheses consideredfor its interior. Although Mars is very similar to the Earth, its interior is not well known;for example, we don't knowif its core is liquid or solid. Only if the core is liquid,the Free Core Nutation (FCN) normal mode exists and can alter the nutationswhich are close to the resonance. From the observed geoids, it is known thatboth planets are not in hydrostatic equilibrium. The departure is larger forMars than for the Earth, and consequently, the implication of considering a convective mantle instead of a mantle in hydrostatic equilibrium described byClairaut's equation for the initial equilibrium state of the planet is largeron the Martian nutations than on the Earth nutations. The consequences of theuncertainty in the core dimensions are also examined and shown to be of a veryhigh influence for Mars if the core is liquid, due to the potential changes inthe FCN resonance. The influence of the presence of an inner core, which isknown to exist for the Earth, could be more important for Mars than for theEarth if the inner core is large. Due to the presence of Tharsis on Mars, thetriaxiality of this planet has, additionally, larger effects than on Earth.     

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.     

On the variation in the geomagnetic dipole over the geological history of the Earth

The global database on the paleointensity, containing determinations of the virtual dipole moment (VDM) for a stable (normal) regime of the geomagnetic field in a time interval of up to 3.5 Ga, is supplemented by new VDM determinations and analyzed. The field generation process started no later than 3–3.5 Ga (earlier data are absent) at the stage of the Earth’s core formation. Since that time, the dipole value has differed from its present value by no more than an order of magnitude, and the deviations that have already been detected tend toward smaller values. The distribution of VDM values in the time interval 0–400 Ma is bimodal, which apparently reflects the presence of two different generation levels of the geomagnetic field distinguished by a relatively large value (close to the present field value) and a relatively small value (approximately half as large as the present value). The total duration of decreased VDM values appreciably exceeds that of increased VDM values (179.1 and 28.6 Myr, respectively). On the whole, data on the paleointensity do not contradict the hypothesis about the dipole nature of the field over the last 400 Myr; however, the number of determinations at high paleolatitudes is too small to draw decisive conclusions on the validity (or invalidity) of the dipole field approximation based solely on paleointensity data.     

Structure of the poleward wall of the trough and the inclination of the geomagnetic field above the EISCAT radar

A special high-resolution routine of the EISCAT radar has been used to investigate the structure and development of the poleward wall of a deep trough in electron density. The feature was tracked by the radar during a 7-hour period under very quiet geomagnetic conditions. The field-aligned nature of the structure enabled an estimate to be made of the inclination of the geomagnetic field above EISCAT that was in good agreement with the current model. Observations of narrow field-aligned enhancements in electron temperature demonstrated that the wall of this trough is a dynamic feature, reforming regularly as the electron density responds on a time scale of tens of minutes to energy input from soft-particle precipitation.