High-precision Magnetic Survey Research Articles

Deep Geological Structure Analysis of the Dongyang Area, Fujian, China: Insights from Integrated Gravity and Magnetic Data

To explore the deep geological structure of the Dongyang area in Fujian, China, gravity data from the area and its surroundings were collected and processed. Additionally, a high-precision magnetic survey was conducted in the Zhongxian region of this area, with subsequent analysis of the magnetic anomalies. Through the integration of regional geological data, a comprehensive analysis was carried out on the characteristics of gravity–magnetic anomalies and deep geological structures in the Dongyang area. The study indicates that the primary portion of the Dongyang area lies southwest of the expansive circular volcanic structure spanning Dehua to Yongtai. Two significant residual gravity anomalies were identified within the region, interpreted as the Xiaoban-Shuangqishan and Dongyang-Lingtouping residual gravity-positive anomalies. In the Zhongxian region, the magnetic field exhibits complexity with notable amplitude variations. Positive anomalies predominate in the western and northern sectors, while localized positive anomalies are prominent in the eastern region. The central area portrays a circular and disordered mix of positive and negative anomalies. Particularly distinctive are the band-shaped and fan-shaped negative anomalies curving from northeast to southeast through the central region. Various positive and negative anomalies of varying strengths, gradients, and orientations overlay both positive and negative magnetic backgrounds in specific locales. Moreover, the Dongyang area showcases well-developed fault structures, primarily oriented in northeast and northwest directions. Leveraging the regional magnetic attributes in conjunction with regional geological data, 39 faults were deduced in the Zhongxian region of the Dongyang area, delineating three promising mineralization zones.

Application of High Precision Magnetic Survey in Deep Exploration of Xiniuliang-Hongwafang, Anlin Area, Henan

Application of High Precision Magnetic Survey in Deep Exploration of Xiniuliang-Hongwafang, Anlin Area, Henan

Exploration indicators of the Jiama porphyry–skarn deposit, southern Tibet, China

Whole-rock geochemical data and compositional balance analysis (CoBA), combined with a magnetic susceptibility model obtained from a high-precision magnetic survey, are useful exploration tools in the Jiama porphyry–skarn deposit, southern Tibet, China. In this paper, three innovative aspects of the model are described that have assisted exploration of the Jiama deposit: an improved geological understanding of a thrust–nappe structure, hydrothermal fluid pathways, and magma mixing; data- and knowledge-driven compositional balance analysis of whole-rock geochemistry; and a high-precision magnetic survey of the deposit. The local strata provided the materials and natural trap for skarn formation, and a site for fluid circulation and porphyry ore precipitation. An interlayer detachment zone, gliding nappe structure, and cylindrical fissure system provided channels for fluid migration, and the Niumatang Anticline provided the accommodation space for the porphyry system. Miocene magma mixing and crustal contamination led to the development of complex mineralization in the Jiama area. The geochemical signatures obtained from CoBA, and the spatial distribution of the strata, structures, igneous rocks, alteration, mineralization, and degree of erosion enable integration of the geochemical and geological data. The “demagnetization skylight” identified by magnetic anomalies and a magnetic susceptibility model obtained with UBCmag3D software revealed the location of a concealed porphyry system. A magnetic susceptibility of 0.014–0.016 was found to identify the location of an interlayer skarn. Our exploration indicators of the Jiama porphyry–skarn deposit can be used to guide ore exploration throughout the region.

Application of High Precision Magnetic Survey in Magnetite Exploration in Southern Shaanxi

Application of High Precision Magnetic Survey in Magnetite Exploration in Southern Shaanxi

Analysis of the geomagnetic field and vertical movement near the intersection of Karjantau and Tavaksay faults in Uzbekistan

Based on the previous researches of geophysics and geodesy, this paper analyzes the geomagnetic field and surface vertical movement near the intersection of Karjantau and Tavaksay faults by using the high-precision magnetic survey technique. Due to the high accuracy of the magnetic survey technique, the magnetic anomalies associated with geological structures and discontinuities are revealed. The measurement results of high-precision total station show the vertical movement difference of observation points over 36 years. When processing the obtained data, the points (Ferma and Visota) are identified as the most mobile points in the Karjantau fault zone. At the points (Skala and Visota) in the north of the Karjantau fault, the observed settlements are −1 mm and −59 mm, respectively. At the southern geodetic observation points (Noviy, Kladbishi and Ferma), they are uplifted by 32 mm, 11 mm and 54 mm, respectively. Based on these data, we can see that in the Tavaksay geodynamic polygon area, the variation of vertical movement values around the Ferma and Visota points is greater than other places. The reason for this phenomenon is that the above points are located in the areas close to the deep Karjantau fault zone.

The application of ground high-precision magnetic survey to the geology and mineral investigation in Huanghe Town area

Three projects have been done to investigate the geology and mineral distribution in Huanghe town area A’nyemaqen-Bayanhar orogen, during the year 2013~2017. Ground high-precision magnetic method on a scale of 1:50000 has been used to study the magnetic character of the geological body and rocks. Correction has been taken in order to normalize magnetic anomaly calculated by different zero points. With the understanding of magnetic character, the distribution of stratum and geological structure can be known. After four years’ job, 16 faults have been recognized and an acid-intermediate intrusive lithosome has been found.

Application of High-Precision Magnetic Survey to the Investigation of Mineral Resources in Halaganlawusu Area, Inner Mongolia

In this paper 1:10 000 high-precision magnetic survey work has been done using GSM-19T proton magnetometer in Halaganlawusu area. There were data processing including gridding, filtering, reduction to the pole, continuation, derivation, and so on. By precise interpretation and inference with magnetic anomaly, the distribution characteristics of basic rock mass was found out. According to the magnetic survey data and geological research, fitting-inversion of measured magnetic section P1, P2 were done. It preliminarily concluded the distribution characteristics of underground ore rock mass and achieved the effect of the geophysical prospecting.

Theoretical Analysis of Magnetic-Electric Prospecting Method for Piping and Seepage Detection of Dyke

On the basis of presenting the piping and seepage detection by magnetic-electric prospecting method, the authors analyzed and testified validity of the method. According to calculated results, the magnitude of magnetic field of artificial current was smaller on section if electrodes and cables were set rationally. Usually, the magnetic field magnitude of piping had several times to more than decuple comparing with magnetic field of artificial current. So, the magnetic abnormity could be detected easily by high-precision magnetometers. At the same time, their curves’ characteristics were different evidently. The analysis result shows that the piping and seepage of dyke can be detected by combining method of direct current supplying and high-precision magnetic survey.

Experimental Study on Chromium Contaminated Sites by Geophysical Methods

Looking into chromium contaminated site is helpful for maintenance and management of the environment. The susceptibility of tailings in industrial processes by combustion is several times than soil. The inorganic substance into the soil and groundwater makes magnetic and electrical difference. So preconditions and physical foundation is based on magnetic and electrical difference; In this paper, we have carried out looking into the chromium contaminated site in the Qinghai Haibei by high-precision magnetic survey(HPMS), high density resistivity(HDR) and induced polarization(IP). The results show that the abnormal body is a three-dimensional body, the volume of the body is calculated roughly based on the features of the abnormal curve and the inversion interpretation; electrical prospecting can investigate and monitor pollution in groundwater, because the concentration of harmful substances is greater than 100mg/L; clay adsorbs heavy metal ions, resulting in lower resistivity and higher rate of charge.