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地壳居里等温面的研究对确定深部磁体结构和了解深部热状态及结构有重要意义.本文对探测居里等温面深度的方法进行了科学地总结,分类和评估,并主要介绍了各种方法的基本原理.较直接的探测居里等温面的方法是根据大地热流值,地温深度关系或岩石矿物实验来确定,但是这种方法在实际中并不常用.最常用的方法是应用航磁和卫星磁数据.根据所研究的目标的不同,磁法又可以被分为两大类:单体磁异常法和组合磁异常法.这两大类下又可以有各种不同的应用技术,其中功率谱分析方法最为流行.虽然没有任何一种方法是完美的,针对组合磁异常的统计功率谱分析方法被认为是较成熟的一项技术,并得到了很多的应用及讨论.组合磁异常的功率谱分析方法的理论基础是SpectorGrant统计模型,这个统计模型很适用于对区域磁异常组合的分析.为了提高分辨率,无论单体磁异常法或组合磁异常法都需要考虑很大的一片研究区域,这样的结果会降低所获得的居里等温面的横向分辨率,由此所获得的居里等温面深度通常只是某一区域平均居里点深度的一级近似.一项比较特别的技术是Mayhew的最初为分析卫星磁数据而建立起来的等层模型方法.这一方法的基本原理是,根据一些校准点,将一等厚度层上所观测到的不同的磁场强度转换为等磁场强度的深度差异.这一技术与功率谱分析方法的一个重要差别在于它不需要对磁体顶部和底部所引起的功率谱进行区分,而这种区分是功率谱分析方法中所必需的.由于对居里等温面深度的探测是一种反演技术并包含了反演中的非唯一性和数学上的不稳定性,在各种方法的应用中应采取谨慎的态度.近年来,自相似和分形理论的应用为这一领域的研究提供了很多崭新的研究机会和科学思想.自相似和分形模型是对SpectorGrant统计模型的完善和发展,因为自相似模型考虑了更真实的磁场强度差异的分形分布.另外,这一新理论也揭示了以前很多种方法中的局限性.
The study of the Curie-Curie isothermal surface is of great significance for determining the structure of the deep magnet and understanding the deep thermal state and structure.This paper scientifically summarizes, classifies and evaluates the method of detecting Curie’s isothermal surface depth, and mainly introduces various methods . The more direct method of detecting the Curie isothermal surface is based on the geothermal heat flow, the relationship between the geothermal depth and the rock mineralogy experiment, but this method is not commonly used in practice. The most commonly used method is to apply aeromagnetic and According to the different objectives of the study, the magnetic method can be divided into two categories: the single magnetic anomaly method and the combined magnetic anomaly method, and under these two categories there are a variety of different application technologies, of which Power spectral analysis is the most popular method.Although no one method is perfect, the statistical power spectrum analysis method for combined magnetic anomalies is considered as a more mature technique and has been widely used and discussed. The theoretical basis of the power spectrum analysis method is the SpectorGrant statistical model, which is very suitable for the analysis of the regional magnetic anomaly combinations.In order to improve the resolution, whether the monomer Both the magnetic anomaly method and the combined magnetic anomaly method require consideration of a large area of study, which results in a reduction of the lateral resolution of the Curie isothermal surface obtained, whereby the Curie isothermal surface depth is usually only one area A first approximation of the mean Curie point depth A relatively specific technique is Mayhew’s original method of modeling a stratiform model developed for the analysis of satellite magnetic data.The basic principle of this method is that according to some calibration points, The different magnetic field intensities observed on the thickness layer are translated into depth differences in equal magnetic field strength.An important difference between this technique and the power spectrum analysis method is that it does not require a distinction between the power spectra caused by the top and bottom of the magnet, This distinction is necessary for the power spectrum analysis method.Because the detection of the Curie isothermal surface depth is an inversion technique and contains the non-uniqueness and mathematical instability in the inversion, Should be taken cautious attitude.In recent years, the application of self-similarity and fractal theory has provided many new research opportunities and scientific ideas in this field of study.Self-similar and sub- The shape model is a refinement and development of the SpectorGrant statistical model because the self-similar model takes into account the more realistic fractal distribution of the difference in magnetic field strength. In addition, this new theory reveals the limitations of many previous methods.