大深度高精度广域电磁勘探理论与技术

Theory and technology of wide field electromagnetic method

矿产资源是实现"两个一百年"奋斗目标的物质基础,随着浅部资源的日渐枯竭,"深地探测"战略提出向地球深部进军。电磁法是深地探测的支柱方法之一,但由于地球内部非均匀性强、耗散介质多,致使地下电磁波传播方程的求解成为世纪难题,因而传统电磁法在探测深度、探测精度和探测准确度方面存在不足,成为"深地探测"战略的关键瓶颈。笔者经过多年的科研攻关,发明了广域电磁法,建立了以曲面波为核心的电磁勘探理论,构建了全息电磁勘探技术体系,实现了频率域电磁法由平面波到曲面波的跨越;研发了具有完全自主知识产权的大深度高精度探测技术与装备,实现了强干扰条件下电磁信号的高信噪比-高精度-快速测量,打破了国外电磁法仪器装备的长期垄断。广域电磁法的探测深度、分辨率和信号强度分别是可控源音频大地电磁法(CSAMT法)的5倍、8倍和125倍,实现了电磁法由粗放到精细的跨越,有力地支撑了面向国家重大需求的"深地探测"战略。

Mineral resources are the material basis for building a moderately prosperous society in all respects by the time the Communist Party of China celebrates its centenary in 2021,and to turn China into a modern socialist country that is prosperous,strong,democratic,culturally advanced,and harmonious by the time the People’s Republic of China celebrates its centenary in 2049.With the depletion of shallow resources,the strategy of‘deep exploration’is proposed for mineral resources.Electromagnetic method is one of the pillar methods for deep exploration.However,due to the strong inhomogeneity and dissipation of the earth,the solution of the propagation of underground electromagnetic wave has become a century-old problem.Therefore,the traditional electromagnetic method has some shortcomings in probe depth,accuracy and accuracy,which has become the key bottleneck of the‘deep exploration’strategy.The author invented a new geophysical exploration method-wide field electromagnetic method(WFEM),established the electromagnetic exploration theory with curved surface wave as the core,and constructed the technical system of holographic electromagnetic exploration.The span of frequency-domain electromagnetic method from plane wave to curved wave was realized.The author also developed a large-depth and high-precision exploration technology and equipment with completely independent intellectual property rights,which realizes high signal-to-noise ratio,high precision and fast measurement of electromagnetic signals under strong interference conditions.The probe depth,resolution and signal intensity of WFEM are 5,8 and 125 times higher than those of CSAMT,respectively,realizing the leap from rough to fine of electromagnetic method.