A brief review of China's MT is given here for 60s, 70s and 80s of last century. Since 90s China's MT had a great progress and a detailed review is introduced. The prospect of MT in 21th century is also discussed.

简要回顾了上世纪60-80年代,我国大地电磁测深工作的起步和发展,较全面地介绍了90年代以来的新进展,并瞻望了新世纪的发展方向.

Geophysics is an observational science. The high precision observational and experimental instruments and equipments take an “outpost” position (key position) in advancement of geophysial science. Therefore, some strategies should be stress in research and manufacture of Geophysical instruments and experimental equipments:(1) Based on the import technology, equipment, copy, and develop the self research, and cooperation, manufacture system, and unceasing go deep into the this field. The purpose is originated new aspect for the research and manufacture of geophysical instruments step by step.(2) Form the research and manufacture system for geophysical instruments and equipments with the characteristics of China, open up the new markets, go to ward the word and standing alone on the forest of international sciences and technology.

地球物理学本质上是一门观测的科学.高精度和高分辨率的观测与实验仪器和设备乃是在地球物理学发展进程中的“前哨”.为此，在我国地球物理学领域里，在对仪器和设备的研究中必须转变观念，即在引进技术，仿造和合作研制的基点上发展自己的研究与研制体系，并在不断深化的进程中，逐步开创中国地球物理仪器研究和研制的新局面，形成具有中国特色的，并具有独立主权和品牌的地球物理仪器及设备的创新研究和研制体制，进而开拓新市场，走向世界，并独立于世界科技之林.

China is just on the eve of rapid industrializing and economic development, which must be supported by great quantities and all kinds of metallic mineral resources. At present the domestic supply is insufficient and the contradiction between supply and demand is increasing.This results in increasing reliance on imports. Proceeding from this premise and ways of solving the problem, the paper analyzes the deep processes of formation and accumulation of metallic minerals and their dynamic response, presents the scientific basis and examples, geophysical methods and technical support of metallic mineral exploration in the crust. According to these the author suggests that: (1) The present resources published by the state are those for exploration and exploitation in the first depth space (0~500 m), which cannot represent all the metallic mineral resources of the country; (2) It is very pressing to carry out metallic mineral exploration and exploitation in the second depth space (500~2000 m); (3) We must rely on new ideas and new concepts, use advanced and highly precise geophysical exploration methods and techniques in exploration and exploitation of deep metallic mineral resources and establish a theoretical and methodological and technological system of mineral exploration with our own characteristics.(4)Importing technology not equals importing renovation idea, and not equals importing renovation ability;(5)Speeding up research and development of new geophysical technology and instrumental equipments.

中国正处在快速工业化和经济腾飞的前夜,必须有大量各类金属矿产资源的支撵,当今国内却供给不足.供需矛盾日益尖锐,导致了对外依存度的不断增长.本文从这一前提和解决的途径出发,分析了金属矿产资源形成与聚集的深层过程和动力学响应、地壳深处金属矿产资源探查的科学依据与例证、地球物理方法和技术支撑.据此提出:(1)当今国家所公布的资源量系指第一深度空间(0~500m)找矿、勘探和开发的资源量,尚不能完全表征全国金属矿产资源量的全部;(2)实施第二深度空间(500~2000m)金属矿产资源的找矿、勘探和开发已迫不及待;(3)在深部金属矿产资源的探查和开发中,必须依靠新的认识和新的理念,采用先进的、高精度的地球物理探测方法和技术,并建立起有自主特色的深部矿产资源探查理论、方法和技术体系.(4)引进技术不等于引进创新思维,更不等于引进创新能力;(5)加速发展和研究地球物理勘探新技术与仪器设备,并逐步产业化.

Sixty years ago, the Chinese geophysicist had a few instruments; but today, the types of the equipments is beyond one thousand. These equipments have been widely used in the exploration of areal geology, the evaluation of mineral resources, the hydrogeology and environmental geology, and even the surveillance of catastrophe. This article gives us a bird’s view of China’s instruments of geological exploration, which includes the history of development and application, the different characteristic of each phase, and some useful strategetic advice to the future.

本文阐述了中国物探仪器应用与研制发展进程中，各个阶段的情况及其特点.同时对今后发展战略和对策提出建议，供各级政府、相关企业、科研单位的决策者和管理者，以及相关的物探科研人员、生产人员参考

By the observation of geophysical field parameters such as seismic velocity, density, magnetism, and electrical conductivity, we have obtained the physical properties and structure features of the earth's crust and upper mantle. Thus scientific evidence further facilitates the understanding of the earth's interior status, the process and mechanism of the movement of crust, and other scientific subjects. Furthermore, such useful information can also lead to the exploration of large-scale mineral deposits. As a primary geophysical method for the detection of the electrical structure of the earth's crust and mantle, magnetotelluric exploration has been widely adopted both in China and foreign countries, and numerous significant research results have been acquired. The seismic and magnetotelluric methods are recognized as two of the dominant methods on the study of the structure of the earth's crust and mantle. They have been proved to be very effective in solving worldwide continent dynamic problems by numerous application cases. However, because the natural electromagnetic field tend to be affected by noises, it is difficult for the MT method to acquire ideal data with high signal-to-noise ratio in the mineral-enriched areas with strong noises. At the same time, the technique of constraining inversion and joint interpretation for seismic and MT data is still not ready for utilization. All the reasons mentioned above limit the accuracy of the process and interpretation of MT data. The project of "experiment and integration of deep detection technology" belongs to the "SinoProbe" project. It takes different areas with both complicated geological conditions and different situation of man-made noises, like the Tibet plateau, the western orogen, and the mountain areas with crystallized rocks in the south china, as target area to study the integration of geophysical techniques for detailed deep detection by utilizing the seismic and MT methods. The electrical structures of these areas are given from the results of the experimental profiles. The subject, which is named "the MT observation experiments and the study of electrical structure of the earth's crust and mantle", will focus on the study of suitable MT acquisition and computation techniques for different noise environment and geological conditions. The constraining inversion and joint interpretation of seismic and MT data will also be discussed. This study aims to enhance the accuracy of deep geophysical detections, and provide examples for the integration of deep geophysical detection techniques and regional geophysical detection with high accuracy. The MT observation experiments located in the northeast edge of Tibet Plateau, the west Qinling Orogen, and the mountain areas with crystallized rocks in Fujian province has accomplished. The result shows that, in these areas with typical geological structures, though difficulties exist during the acquisition, and the noise is very strong in some areas, it is still possible to acquire the MT data with high quality and consequently get a reliable model of the underground electrical resistivity by choosing proper technique for field observation and taking discreet computation. The results from this experimental project will become important technical support and insurance for the realization of the scientific objectives of the “experiment and integration of deep detection technology” project.

通过对地震波速度、密度、磁性、导电性等物理场进行观测，研究地壳与上地幔的物性与结构特征，将为研究地球内部物质状态、地壳运动过程及其动力学机制等科学命题提供科学依据，同时也将为寻找深部大型矿床提供信息。大地电磁深探测方法作为研究地球壳幔电性结构的主要地球物理方法，在国内外完成了大量探测工作，取得了许多重要的研究成果。在研究壳幔构造方面，大地电磁法和地震方法一起被视为两大支柱方法，在世界范围内解决大陆动力学问题方面已有许多成功的应用范例。但由于大地电磁探测以天然电磁场作为场源，在矿集区等强干扰地区往往很难采集到高信噪比的数据，抗干扰能力较弱。同时，大地电磁与地震数据的约束反演以及联合解释目前尚没有达到实用化，这些都限制了大地电磁数据的处理及解释精度。“深部探测技术与实验研究”（SinoProbe）专项下属的“深部探测技术实验与集成”项目将选择青藏高原、西部造山带与华南山区结晶岩等复杂地质条件和不同人文干扰水平地区，以大地电磁探测与地震探测作为主要手段，研究深部精细地球物理探测技术的集成，并且通过实验剖面研究这些实验区的壳幔结构特征。其中的“大地电磁测深大剖面观测实验与壳/幔三维电性研究”课题，将通过在实验区的大地电磁观测实验，研究适用于不同地质条件及干扰水平地区的大地电磁数据采集方法技术以及精细处理与反演方法，同时探讨大地电磁数据与地震数据的约束反演以及联合解释。该研究将提高深部地球物理探测精度，为深部精细地球物理探测方法技术集成以及区域地球物理精细探测提供范例。已经完成的青藏高原东北缘西秦岭造山带和福建结晶岩地区的大地电磁观测试验表明，在这些典型地质构造区域，虽然存在施工困难，干扰水平大等各种不利因素，但只要采取合适的野外观测技术，并通过数据精细处理与反演计算，是能够获得高质量的大地电磁数据以及可靠的电阻率分布模型。试验所取得的成果，将为实现“深部探测技术实验与集成”项目科学目标和研究任务提供重要的技术支撑与保障。

Based on a study of the high-power and multi-functional launching system of the electromagnetic method and its corresponding key technologies; the authors developed a high-power (70 kw) and multi-functional (with the power supply function of CSAMT and IP) intelligent transmitting prototype that has independent intellectual property rights. Accordingly, the multi-functional (with the measurement function of AMT, CSAMT and IP) receiving prototype was also designed and developed. As a result, the matched data processing technology of the multi-functional electromagnetic system has been successfully resolved. A comparative trail was carried out between the self-developed multi-functional electrical system and the GDP32 system, with some good results achieved.

通过对大功率多功能电磁法发射系统所涉及关键技术的研究, 研制出具有自主知识产权的大功率(70kw)多功能(具有CSAMT, IP供电功能)电磁发射样机; 通过对多功能电磁法接收系统所涉及关键技术的研究, 研制出多功能(具有AMT、CSAMT, IP测量功能)电磁法接收样机; 研究开发了与多功能仪器样机相配套的数据处理技术; 在试验区开展了自主研制的多功能电法系统与GDP32的场地对比试验, 取得了良好效果

混场源电磁法利用大地电磁法理论对数据进行解释处理,应用的频率范围在0.1Hz—75KHz之间,以人工发射的电磁场弥补天然电磁场在高频段信号微弱的不足,可以探测地下几米到一千米深度左右的电阻率信息。在理论仿真的基础上,本文根据系统要求特点,设计了以谐振方式发射的磁性场源并研究设计了以多频信号发射的电性源,以实现不同工作条件下的人工电磁场发射。为满足对电磁信号的有效接收,详细研究了接收系统的几个关键技术问题。针对弱磁信号的检测,设计了宽频磁感应式传感器,通过研究磁传感器的校准技术,给出了传感器灵敏度及相位偏移的测试校准方法。对于电场信号检测,研究了电场信号的本地放大问题,以提高有用信号的信噪比。针对电场和磁场的弱信号采集,设计实现了具有自校准功能的多通道同步24位数据采集系统。各种实验证明,通过几个关键技术的研究,混场源电磁系统在人工场源发射上更具有灵活性；自主设计的磁传感器在灵敏度、带宽等方面能够满足实际测试需要,打破了对国外进口传感器的依赖；由于系统能够随时进行磁传感器和通道的校准,减小了因时间及温度漂移对测量精度的影响；系统内部采用的高性能DSP芯片和PC104处理器也都为整体性能提升提供了可靠保障。

Distributed data acquisition technology, which is widely used in seismic exploration, was introduced in electromagnetic geophysical system. The measured electromagnetic signals possess the characteristics of broadband, large dynamic range and strong interference. Low-noise analog signal conditioning circuit was designed and a high-performance data acquisition system was constructed using 24-bit Δ-Σ Analog-to-Digital Converter (ADC) and Field Programmable Gate Array (FPGA). In this data acquisition system, a microcontroller with peripheral modules was used to achieve workflow control, data storage and transmission. The test results of main technical specifications, and flume model and field experiments show that the system is feasible and accurate, which meets the needs of data acquisition of distributed electromagnetic exploration.

将地球物理勘探中广泛应用于地震数据采集的分布式采集技术引入电磁探测仪器,针对被测电磁场信号宽频带、大动态范围、强噪声干扰的特点,通过设计低噪声的模拟信号调理电路,采用24位Δ-Σ结构模数转换器(Analog-to-digital,ADC)和现场可编程门阵列(Field programmable gate array,FPGA)构建了高性能的数据采集系统。利用微控制器及其外围功能模块实现了数据采集系统的工作流程控制、数据存储和传输。主要技术指标测试和水槽模型及野外勘探对比试验结果表明:该系统性能先进,测量准确,能够满足分布式电磁探测数据采集的需求。

With the rapid development of electronic and information technology, the application of embedded technology has been a main stream in developing instrument for electromagnetic exploration nowadays. The traditional application of the embedded device based on microcontroller can not meet the requirement of the electromagnetic prospecting instrument. In this paper, the features of embedded system are reviewed. The microprocessors of ARM architecture and X86 architecture and various embedded operating systems such as MS-DOS, Windows CE, Linux and μC/OS-II widely used in electromagnetic prospecting instrument are analyzed and compared respectively. The conclusion is that the application of embedded microprocessor with high performance and low power consumption and the application of powerful embedded operating system will become a trend in developing electromagnetic prospecting instrument.

随着电子技术和信息技术的迅速发展,嵌入式技术成为当今电磁法勘探仪器的主流技术.以单片机为核心的电磁法勘探仪器已逐渐不适应电磁法勘探的需求.本文通过分析嵌入式系统的特点,针对目前电磁法勘探仪器主要采用的X86和ARM嵌入式微处理以及MS-DOS、Windows CE、Linux和μC/OS-II嵌入式操作系统进行了分析和对比.指出采用高性能、低功耗的嵌入式微处理器和功能强大的操作系统将是今后电磁法仪器的发展趋势.

广域电磁法是何继善院士提出的。他针对现有可控源电磁法要求“远区”测量而导致信号微弱和一次只发送、接收一个频率的缺点,将现有可控源电磁法理论进行了创新,并发明了伪随机信号。伪随机信号包含多个振幅接近、频率在对数坐标分布均匀的多频信号,是一种理想的电磁法勘探场源。广域电磁法继承了CSAMT场源可控的优点,从而克服了MT场源随机性和信号微弱的缺点。该方法并不沿用“卡尼亚视电阻率”计算公式,而是用电磁场的全域精确公式迭代计算提取视电阻率,这样可以在“非远区”进行测量,大大拓展了人工源电磁法的观测范围,提高了观测速度、精度和野外勘探效率。广域伪随机电磁法是一种全新的独具特色的电磁勘探方法。 广域伪随机电磁测深仪以广域电磁法理论为指导,在设计思路和原理上突破了一些陈旧观念,打破国外电磁法仪器一统天下的局面。它实现了自主创新,拥有自主知识产权,推动了电磁法仪器的进一步发展。 广域视电阻率可以通过测量电磁场的任一分量获得,但测量电场的水平分量Ex相对简便。结合现代电磁法仪器新技术,本文研究了基于E-Ex广域电磁测深法的测量仪器系统,包括适合在深部油气藏地区实施深部三维电磁勘探的大功率伪随机信号发送机和广域电磁接收机。 本文首先根据伪随机信号的基本原理,论述了伪随机信号波形产生机制和伪随机信号发送控制器的设计；详细探讨了伪随机信号发送机的功率设计、大功率整流滤波以及逆变技术和实现方法；设计了200KW大功率整流滤波器、IGBT逆变器Matlab模型并进行仿真分析；阐述了IGBT驱动与无源无损缓冲电路设计,实现了IGBT的过压、过流检测与保护电路设计；分析了发送机所用大功率半导体器件的耗散功率设计,采用新型热管散热技术为功率半导体散热,保证大功率伪随机信号发送机的可靠运行。 本文还详细分析了E-Ex广域电磁有效信号和干扰信号的频率、振幅等特征；探讨了模拟、数字选频技术,实现了基于GPS同步的相干检测；提出了接收信号数字化思想,详细推导了伪随机多频信号的提取方法,用matlab进行了仿真分析,并在DSP处理器里实现了提取算法；设计了低噪声精密模拟信号调理电路,实现了高速、高分辨模数转换；阐述了基于TMS320C6713 DSP核心系统以及网络通信接口、数据采集接口和GPS接口设计；实现了DSP软件功能设计和程序编制。提出并实现了基于光纤通信的网络通信系统和基于Canopy的无线网络通信系统,实现了广域电磁三维勘探。 广域电磁接收机室内电阻网络指标测试(包括一致性、稳定性等),以及广域电磁测深仪器系统(包括200KW发送机和多台接收机)在油田地区的野外试验表明：研制的广域电磁测深仪达到了设计指标,基本满足野外三维电磁勘探要求,为实现和推广广域电磁法提供了必备条件,具有重要的实际应用意义。 论文获得了国家自然科学基金项目：科学仪器基础研究专项基金“广域电磁测深仪的基础研究(40827002)”的资助。

地球深部探测技术装备为实施国家地壳探测工程战略计划、揭示地球深部奥秘提供技术保障，其发展水平将决定在辽阔的国土和海洋区域大面积、大深度获取数据和信息的能力。瞄准国际前沿装备技术，从国家高科技发展战略出发，针对复杂地质环境的探测能力和效率，自主研发深部探测仪器装备。基于研究现状和基础，从6个关键技术开展工作，分阶段落实探测工程战略计划，迅速提升整体技术水平。通过跨部门联合建设研发基地、汇集优秀人才、培训人员，引进、消化、吸收国外高端产品技术，加速完善自主创新、产学研用相结合的发展模式，迅速改变我国深探仪器装备长期依赖进口局面，在较短时期内完成从起步到成熟阶段的跨越式发展。

Marine CSEM is an effective method for Methane Hydrate detection, which is validated by foreign Methane Hydrate exploration tests. The key work of marine CSEM is developing equipment which acquires CSEM signal and must be of high precision, high robustness, and low power .To acquire ultra wide band and high dynamic range CSEM signal intelligently, we have designed measurement circuit based on Linux and ARM9, developed the Linux drivers for data acquisition under Linux 2.4 kernel. This paper describes the elements of acquire hardware and char devices driver, example of drivers for SSC and locking GPS.

国外的水合物探测试验证明，可控源电磁法是探测天然气水合物的有效方法之一.开展海底可控源电磁法工作的重点之一在于研制高精度、高可靠、低功耗观测海底可控源电磁信号的设备.为可靠地观测海底可控源电磁场宽频带、大动态范围信号，设计了以Linux与ARM9相结合的测量电路，并开发了Linux2.4内核下的设备驱动程序.本文分别论述了采集硬件原理，Linux字符设备驱动模型，SSC和GPS对钟驱动实例.

为通过MT方法了解大陆岩石圈电性结构,开发了完全自主知识产权的新型大地电磁采集器.介绍了采集器原理,采用ARM平台与LINUX操作系统相结合的硬软件方案,引入GPS授时与恒温晶振实现多点同步技术、低噪声技术、大容量存储技术、低功耗技术以及嵌入式Linux软件技术.通过与国外同类仪器的野外对比试验表明,仪器指标满足标准MT测量要求.