Journal articles: 'Aeromagnetic data image processing'

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Kowalik, W. S., and W. E. Glenn. "Image processing of aeromagnetic data and integration with Landsat images for improved structural interpretation." GEOPHYSICS 52, no. 7 (July 1987): 875–84. http://dx.doi.org/10.1190/1.1442358.

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Digital image processing of aeromagnetic data from three mineral prospects significantly improved the existing structural interpretations that were made from contour maps of the aeromagnetic data. Useful image‐processing techniques include (1) presentation as small‐scale, gray‐level images, (2) local contrast enhancement, (3) artificial illumination, and (4) directional filtering. Digital processing also enables direct comparison between Landsat data and aeromagnetic data. Interpretations were improved by the study of the integrated data sets. Images of aeromagnetic data from one prospect in a Precambrian granite‐greenstone terrane show major folds and faults that were not previously recognized from contour maps of the aeromagnetic data. A Landsat Multispectral Scanner (MSS) image shows the subtle surface expression of two folds. The newly identified structures point to additional prospective ground in the search for volcanogenic massive sulfide deposits in the area. Aeromagnetic data from a second prospect are complicated by a young, north‐south striking, strongly magnetic, diabase dike swarm. Directional filtering and artificial illumination of the aeromagnetic data effectively remove the response of the dikes and enhance the earlier structural and lithologic features. The combined interpretation of illuminated aeromagnetic and registered Landsat Thematic Mapper (TM) images for a third prospect added several significant faults that were previously unrecognized from separate interpretations of contour maps of aeromagnetic data and the Landsat image.

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Yigui, Lionel Cedric, Theophile Ndougsa-Mbarga, Arsène Meying, and Olivier Ulrich-Igor Owono-Amougou. "Detection of sub-surface fractures based on filtering, modeling, and interpreting aeromagnetic data in the Deng Deng – Garga Sarali area, Eastern Cameroon." Open Geosciences 14, no. 1 (January 1, 2022): 646–62. http://dx.doi.org/10.1515/geo-2022-0357.

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Abstract The aeromagnetic anomalies existing in the Deng Deng – Garga Sarali region in Eastern Cameroon were filtered for a structural study of the region’s subsoil. This study presents the results of lineaments and fractures extracted by aeromagnetic image processing methods and compared with scientific data to obtain potential terrain models in the study area. The methodological approach used is based on the filtering of aeromagnetic image by using the analytical signal, the Euler deconvolution, and 2D3/4 modeling, to establish the maps of the lineaments and faults of the study area and their characteristics, and also to propose three models from three previously chosen profiles. Analytical signal and Euler deconvolution techniques have been applied to aeromagnetic anomalies to highlight the relationship between the depth and the source of magnetic anomalies, two parameters whose importance in geoexploration and modeling of the body is essential. We identified the potential contacts by interpretation of the deep Euler anomalies, these are highlighted on the basis of a certain similarity between the maps of the total magnetic field, the map of the analytical signal, the map of the maxima of the gradient horizontal, and geological map. Euler’s map of solutions correlates well with the edges of certain superficial and deep causative bodies.

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Soulaimani, Ayoub, Saïd Chakiri, Saâd Soulaimani, Ahmed Manar, Zohra Bejjaji, Abdelhalim Miftah, Mohammed Amine Zerdeb, Yaacoub Zidane, Mustapha Boualoul, and Anselme Muzirafuti. "Semi-Automatic Image Processing System of Aeromagnetic Data for Structural and Mining Investigations (Case of Bou Azzer Inlier, Central Anti-Atlas, Morocco)." Applied Sciences 12, no. 21 (November 7, 2022): 11270. http://dx.doi.org/10.3390/app122111270.

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Numerical analysis of geophysical data to uncover Precambrian belts and probably to enclose mineral deposits is becoming once more communal in mining activity. The method is founded on typifying zones branded to comprehend deposits and looking for analogous areas. The proposed work outlines a semi-automatic image processing system for the structural and mining investigation of the Bou Azzer inlier, which varies from preceding approaches as it is centered only on aeromagnetic data. The aeromagnetic signature of what seem to be geologically expressive features are pursued within the aeromagnetic items. Cobalt and associated mineralizations in the Bou Azzer inlier are recognized to arise nearby main crustal discontinuities revealing as significant shear zones, which turn act as drains for mineralizing fluids. Mineralization occurs in sectors of structural complexity beside the shear zones. Developing towards the semi-automatic uncovering of such regions, the furthermost prospective extents are those everywhere inferred structural complexity occurs next to the regions of magnetic discontinuity. The proposed method is mainly based on the approach developed by the center for exploration targeting. The study was led by means of aeromagnetic data from the Bou Azzer inlier, which is considered one of the most productive and prospective regions for minerals and base metal mineralization in Morocco. The combined results obtained from geological and geophysical data prove that prospective areas have a dominant trend of NNE-SSW, NW-SE, NNW-SSE, E-W, and NE-SW directions. The CET Grid and Porphyry Analyses show that the probable porphyry mineral deposit locations mainly concentrated in the center of inlier, the Foum Zguid dyke, and northern and eastern part, which correspond to the Bou Azzer ophiolitic complex and platform deposits of the Lower Neoproterozoic Tachdamt-Bleïda.

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Naprstek, Tomas, and Richard S. Smith. "A new method for interpolating linear features in aeromagnetic data." GEOPHYSICS 84, no. 3 (May 1, 2019): JM15—JM24. http://dx.doi.org/10.1190/geo2018-0156.1.

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When aeromagnetic data are interpolated to make a gridded image, thin linear features can result in “boudinage” or “string of beads” artifacts if the anomalies are at acute angles to the traverse lines. These artifacts are due to the undersampling of these types of features across the flight lines, making it difficult for most interpolation methods to effectively maintain the linear nature of the features without user guidance. The magnetic responses of dikes and dike swarms are typical examples of the type of geologic feature that can cause these artifacts; thus, these features are often difficult to interpret. Many interpretation methods use various enhancements of the gridded data, such as horizontal or vertical derivatives, and these artifacts are often exacerbated by the processing. Therefore, interpolation methods that are free of these artifacts are necessary for advanced interpretation and analysis of thin, linear features. We have developed a new interpolation method that iteratively enhances linear trends across flight lines, ensuring that linear features are evident on the interpolated grid. Using a Taylor derivative expansion and structure tensors allows the method to continually analyze and interpolate data along anisotropic trends, while honoring the original flight line data. We applied this method to synthetic data and field data, which both show improvement over standard bidirectional gridding, minimum curvature, and kriging methods for interpolating thin, linear features at acute angles to the flight lines. These improved results are also apparent in the vertical derivative enhancement of field data. The source code for this method has been made publicly available.

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McDonald, A. J. W., C. J. N. Fletchert, R. M. Carruthers, D. Wilson, and R. B. Evans. "Interpretation of the regional gravity and magnetic surveys of Wales, using shaded relief and Euler deconvolution techniques." Geological Magazine 129, no. 5 (September 1992): 523–31. http://dx.doi.org/10.1017/s0016756800021683.

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AbstractRegional gravity and aeromagnetic data of Wales have been processed using a variety of techniques. Image processing has greatly assisted qualitative interpretation, whilst automated procedures have provided additional quantitative information. The shaded relief images emphasize gradients in the potential fields, and are useful for displaying strong linear features. The Euler deconvolution method produces plotted solution maps, which define the position of the source of the gravity and magnetic anomalies. Euler solution maps of Wales and the adjacent continental shelf are presented for the first time. These maps are interpreted in relation to the known geology, with special emphasis on the Lower Palaeozoic Welsh Basin. It is proposed that the Euler solutions define a network of fault-bounded blocks within the Precambrian basement.

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Thurston, Jeffrey B., and Richard S. Smith. "Automatic conversion of magnetic data to depth, dip, and susceptibility contrast using the SPI (TM) method." GEOPHYSICS 62, no. 3 (May 1997): 807–13. http://dx.doi.org/10.1190/1.1444190.

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The Source Parameter Imaging (SPI™) method computes source parameters from gridded magnetic data. The method assumes either a 2-D sloping contact or a 2-D dipping thin‐sheet model and is based on the complex analytic signal. Solution grids show the edge locations, depths, dips, and susceptibility contrasts. The estimate of the depth is independent of the magnetic inclination, declination, dip, strike and any remanent magnetization; however, the dip and the susceptibility estimates do assume that there is no remanent magnetization. Image processing of the source‐parameter grids enhances detail and provides maps that facilitate interpretation by nonspecialists. The SPI method tests successfully on synthetic profile and gridded data. SPI maps derived from aeromagnetic data acquired over the Peace River Arch area of northwestern Canada correlate well with known basement structure and furthermore show that the Ksituan Magmatic Arc can be divided into several susceptibility subdomains.

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Chacksfield, B. C., W. De Vos, L. D'Hooge, M. Dusar, M. K. Lee, C. Poitevin, C. P. Royles, and J. Verniers. "A new look at Belgian aeromagnetic and gravity data through image-based display and integrated modelling techniques." Geological Magazine 130, no. 5 (September 1993): 583–91. http://dx.doi.org/10.1017/s0016756800020884.

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AbstractDigital processing and image-based display techniques have been used to generate contour and shaded-relief maps of Belgian aeromagnetic data at a scale of 1:300000 for the whole of Belgium. These highlight the important anomalies and structural trends, particularly over the Brabant Massif. North and vertically illuminated shaded-relief plots, enhanced structural belts trending west–east to northwest–southeast in the Brabant Massif and west–east to southwest–northeast in the core of the Ardennes. The principal magnetic lineaments have been identified from the shaded-relief plots and tentatively correlated to basement structures. Most short lineaments are correlated with individual folds while the more extensive lineaments are correlated with large scale fault structures. Magnetic highs within the Brabant Massif are attributed to folded sediments of the Tubize Group. The magnetic basement in the east of Belgium is sinistrally displaced to the north by an inferred deep NNW–SSE crustal fracture. The Bouguer anomaly map of Belgium identifies the Ardennes as a negative area, and the Brabant Massif as a positive area, with the exception of a WNW–trending gravity low in its western part. The southern margin of the Brabant Massif is defined by a steep gravity gradient coincident with the Faille Bordiere (Border Fault). Trial modelling of the gravity and magnetic data, carried out along profiles across the Brabant and Stavelot massifs, has identified probable acid igneous intrusions in the western part of the Brabant Massif, and a deep magnetic lower density body underlying the whole Ardennes region, which is thought to be a distinctive Precambrian crustal block.

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Pettifer, G., A. Tabassi, and B. Simons. "A NEW LOOK AT THE STRUCTURAL TRENDS IN THE ONSHORE OTWAY BASIN, VICTORIA, USING IMAGE PROCESSING OF GEOPHYSICAL DATA." APPEA Journal 31, no. 1 (1991): 213. http://dx.doi.org/10.1071/aj90016.

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Although the Otway Basin is oriented west-north-westerly, and previously recognised major structural elements follow a similar trend, other structural trends have been found on recently obtained geophysical data.In 1989, an aeromagnetic and radiometric survey of the onshore Otway Basin was completed for the Victorian Department of Industry and the Bureau of Mineral Resources, Geology and Geophysics. This survey, together with a recent gravity compilation by the Geological Survey of Victoria, enables analysis of magnetic and gravity data trends reflecting basement and intra-basin structure.The trend analysis was carried out using modern image processing techniques including simulation of real-time sun-angles of the magnetic and gravity data, and composite images of the radiometric data, to highlight lineaments. This technology enables integration of magnetic, gravity, radiometric and, potentially, seismic, Landsat, topography and bathymetry data for basin structure analysis.The magnetic, gravity and radiometric trend analysis was compared to an earlier Landsat study (Baker, 1980) and a previous seismic data compilation of the Otway Basin (Megallaa, 1986).The present study has revealed the significance of major early Palaeozoic north-south and east-north-east to easterly trends. The latter trends have not previously been identified or discussed in earlier basin reviews. There appears to be a difference between trends reflected in the radiometric and seismic data and trends apparent in the gravity and magnetic data. This could indicate a change in principal stress directions during the evolution of the basin. The shape of the northern margin of the basin appears to be controlled by major north-easterly structures.

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Rosa, João Willy Corrêa, José Wilson Corrêa Rosa, and Götz Bokelmann. "Lateral variation of crustal properties from aerogeophysical data in northern Brazil." GEOPHYSICS 82, no. 5 (September 1, 2017): J39—J60. http://dx.doi.org/10.1190/geo2016-0206.1.

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A new method is proposed for the study of crustal azimuthal anisotropy, and the lateral variation of other crustal aerogeophysical parameters, using a quantitative approach. The processing of a large, newly acquired, high-resolution set of aerogeophysical data is considered using the existing Radon transform and the geostatistical analysis approaches. The data set includes an area of the Guyana shield, in northern Brazil, which was not included in previous surveys. The area is covered by dense rain forest vegetation and thick soil layers. Parameterization was performed considering the possible anisotropic character of the geophysical 2D data. Application of the newly proposed geostatistical data processing yielded high-resolution images of the lateral variation of quantitative geophysical parameters, which indicate good correlation with previously determined seismic anisotropy in the area. Average anisotropy as measured by the Radon transform and variogram analysis is scale dependent. At scales greater than [Formula: see text], the results seem to match those of the previous seismic studies. Images of the derived quantitative parameters from magnetic and radiometric data in the shield area indicate sharp changes that follow the known geologic changes observable in the survey area. Observed large-scale anisotropy in the area seems to be autocorrelated with two different geochronological provinces of the Amazonian craton. Application of the new technique to two other lower resolution aeromagnetic surveys located on the Amazon basin has produced two different results, including one successful data treatment of the aeromagnetic survey. The results obtained for this area indicate that the sedimentary cover seems to play almost no role in the observed magnetic anomaly anisotropy in the middle Amazon basin area. Most of the observed magnetic anomalies appear to be controlled by the continuing geologic features of the cratonic basement.

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Rahman, Aqeel, Inass Almallah, and Ahmed Mousa. "Lineaments Tracing of Magnetic Sources Depending on the Aeromagnetic Data: Case Study in Salman Basin and Surrounding Areas, Southern Desert of Iraq." Iraqi Geological Journal 55, no. 1D (April 30, 2022): 184–98. http://dx.doi.org/10.46717/igj.55.1d.14ms-2022-04-30.

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This study deals with the processing and analysis of aeromagnetic data for an area covering the region of Salman Basin within AL- Muthanna, Iraq. The objective of this study is to use the available satellite images and aeromagnetic data to investigate the boundaries of geological structures. For further understanding of the tectonic of the study area, the Centre for Exploration Targeting Grid Analysis extension which is available in Oasis montaj software was applied to the data. It is proposed that it provides unbiased results, but to check the results Tilt Derivative or local phase derivative is used where the zero-contour line of the tilt derivative strongly delineates the edges of structures. Also, the drainage pattern for the basin is done using Geographic Information System and Digital Elevation Model raster to see if the drainage is affected by the subsurface lineaments that are determined using the Centre for Exploration Targeting technique. As a result, the deep main linear features follow the general trend of the main faults that formed the Salman Basin. The new lineaments were discovered using the Exploration Targeting grid analysis, zero contour of. There are two systems of lineaments in the present study area. The first set is taken the NW-NE direction perpendicular to the extensional structures, while the second set has the NS-EW direction.

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Bozzo, E., F. Ferraccioli, M. Gambetta, G. Caneva, M. Spano, M. Chiappini, and D. Damaske. "Recent progress in magnetic anomaly mapping over Victoria Land (Antarctica) and the GITARA 5 survey." Antarctic Science 11, no. 2 (June 1999): 209–16. http://dx.doi.org/10.1017/s0954102099000279.

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Magnetic anomaly mapping is used to interpret crustal structure and tectonic evolution of Victoria Land and of the adjacent Ross Sea. Previous interpretation of magnetic anomalies verified seismic and gravimetric findings in the Ross Sea by placing additional constraints both on crustal structure and magmatism of the West Antarctic rift system. An aeromagnetic map of the central-southern part of Victoria Land produced in the framework of the GITARA project, provides new crustal images of part of the Transantarctic Mountains rift shoulder. The map was interpreted to study the transition between the Wilson Terrane and the Precambrian East Antarctic Craton, the extent and distribution of Jurassic tholeiitic magmatism, and the occurrence of post- Jurassic faulting oblique to the rift basins. A compilation with adjacent aeromagnetic data was recently used to study the structures inherited from the Palaeozoic terranes and their reactivation as major fault zones separating different crustal blocks along the TAM rift shoulder. Additional aeromagnetic coverage over a 35 500 km2 sector of northern Victoria Land was acquired during the GITARA 5 (1996/97) survey. The flight altitude was 9000 ft and profile line spacing was 4.4 km for the regional grid and 2.2 km for the detailed one, with a tie line interval of 22 km. Standard processing techniques, optimized with microlevelling procedures were applied to the data to produce a 1:250 000 magnetic anomaly map. The processed GITARA 5 magnetic dataset is a new tool to study the structure of the Rennick Graben, and its relationship to the Palaeozoic Wilson Terrane-Bowers Terrane and Robertson Bay Terrane suture zone. The new map also represents important progress towards a magnetic anomaly compilation over the whole of Victoria Land, since it links previous efforts near the Pacific Coast with those near the Ross Sea.

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Li, Shu-Ling, and Yaoguo Li. "Inversion of magnetic anomaly on rugged observation surface in the presence of strong remanent magnetization." GEOPHYSICS 79, no. 2 (March 1, 2014): J11—J19. http://dx.doi.org/10.1190/geo2013-0126.1.

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We study the inversion of magnetic data acquired over a rugged observation surface and where the buried source bodies have strong remanent magnetization that leads to unknown total magnetization directions. These factors pose significant challenges for processing and inversion of such data. To tackle the challenges from both a rugged observation surface and an unknown magnetization direction, we propose a strategy through the joint use of the equivalent source technique and 3D amplitude inversion to obtain 3D magnetization strength. We use equivalent source processing to calculate the amplitude data in the space domain because the use of the wavenumber-domain method is invalid due to large variations in the data elevation. We then carried out an amplitude inversion to generate a 3D subsurface distribution of the magnitude of the total magnetization vector. The results from a synthetic example and aeromagnetic data in Daye Mine in China showed that this approach is effective and images the magnetic units whose contact zones with the limestone country rock host the mineralization. The method is general and can be applied to a variety of cases with similar challenges.

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West, Gordon F., and Richard E. Ernst. "Evidence from aeromagnetics on the configuration of Matachewan dykes and the tectonic evolution of the Kapuskasing Structural Zone, Ontario, Canada." Canadian Journal of Earth Sciences 28, no. 11 (November 1, 1991): 1797–811. http://dx.doi.org/10.1139/e91-160.

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By digital image processing of federal–provincial aeromagnetic survey data for the south-central Superior Province, we have obtained an improved picture of the distribution of dykes in the huge Matachewan mafic dyke swarm (2454 Ma). We deduce from it a picture of post-emplacement deformation in the vicinity of the uplifted granulite gneisses of the Kapuskasing Structural Zone (KSZ). Matachewan dykes are emplaced in three subswarms. The two easterly subswarms are clearly truncated by the KSZ's eastern boundary faults. The western subswarm shows an open Z-bend as it crosses the KSZ, but it does not reveal any major fault offset. On the plausible assumption (supported by paleomagnetic data) that the subswarms were originally intruded radially, the horizontal strain suffered by the KSZ since emplacement of the dykes is mainly a northeast–southwest-trending band of dextral transcurrent deformation, which in the northeast is discontinuous and concentrated in a fault (horizontal offset 60–80 km) and in the southwest widens through a series of horsetail splays into an ~80 km wide zone of distributed strain. The KSZ is believed to have formed by a major, crustal-scale, thrust uplift along the KSZ's southeastern margin. Some thrusting is recorded by the dyke pattern, but this can account for only part of the ~20 km of differential uplift seen in the KSZ. Most likely, the mainly transcurrent deformation recorded by the dykes is a secondary event, and the primary period of thrust uplift predated dyke injection.

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DENTITH, M. C., A. W. R. BEVAN, J. BACKHOUSE, W. E. FEATHERSTONE, and C. KOEBERL. "Yallalie: a buried structure of possible impact origin in the Perth Basin, Western Australia." Geological Magazine 136, no. 6 (November 1999): 619–32. http://dx.doi.org/10.1017/s0016756899003386.

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An enigmatic buried structure, located in Mesozoic sedimentary rocks in the Perth Basin, Western Australia, was discovered in 1990 by Ampol Exploration. The basin-like Yallalie structure (centred on 30° 26′ 40.3″ S, 115° 46′ 16.4″ E) is circular in plan view and about 12 km in diameter. High-resolution, seismic-reflection profiles across the structure show a basin-shaped area of chaotic reflections that extend to a depth of approximately 2 km below the surface. The structure has sharp boundaries with surrounding faulted, but otherwise relatively undisturbed, rocks. In the centre of the structure there is an uplifted area approximately 3–4 km across, similar to those described from complex meteorite impact structures. The seismically defined structure coincides with a circular topographic depression, and image processing of digital elevation data has allowed recognition of concentric and radial structures extending as far as 40 km from the centre of the depression. Gravity surveys show the structure to be associated with a positive gravity anomaly of about 30 gu. Aeromagnetic surveys have defined annular anomalies associated with the central uplifted section, and possibly margins, of the structure. A search for siderophile element enrichments (by neutron activation analysis) in the rocks of the structure, which would indicate the presence of a meteorite component, proved negative. Quartz grains in cores that penetrate the structure show the development of prismatic cleavage fractures and irregular, slightly curved planes formed by brittle fracture. An allochthonous breccia of Late Cretaceous rocks occurs a few kilometres west of the western margin of the structure. Quartz grains from a thin veneer of Tertiary sediments that drape the structure are essentially undeformed. However, multiple sets of closely spaced planar deformation features in quartz, characteristic of highly shocked rocks, have yet to be observed in the rocks of the Yallalie structure and the allochthonous breccia. The morphology of the Yallalie structure determined from topographic and geophysical data suggests strongly that it is of impact origin. Geological and geochemical evidence is equivocal, but is not inconsistent with this interpretation.

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Oni, Olubukola A., and Ahzegbobor P. Aizebeokhai. "Aeromagnetic data processing using MATLAB." IOP Conference Series: Earth and Environmental Science 993, no. 1 (March 1, 2022): 012017. http://dx.doi.org/10.1088/1755-1315/993/1/012017.

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Abstract This study focuses on the evaluation of magnetic field variation in a two-dimensional plot in form of a contour map by carrying out interpolation on the magnetic field data and mapping regional structures to infer the direction of dykes. To pinpoint areas of magnetic highs and lows, MATLAB program was used to delineate magnetic field trends on the data. The program was also used to produce graphical, colourized and contoured plots of data from XYZ files (data with random locations) using interpolation functions. The program was used for both gridding and smoothening of the magnetic field data and also allow the setting of contour values and utilization of vivid colour scales. The aeromagnetic data vector may contain outliers which are due to instrumental error and data extraction during field data collection. These outliers were removed and replaced using three interpolation methods including linear, nearest-neighbour and cubic spline to have a non-distorted representation plot and they were also used to fit surfaces to the gridded data. The result shows that the piecewise cubic spline interpolant contour plot has finer precision with higher details at the output edges. From the piecewise linear surface B(X,Y), where X is normalized by mean 2.235e+05 and standard deviation of 3.202e+04 and Y is normalized by mean 7.809e+05 and standard deviation of 551. The residual magnetic intensity plot shows the magnetic field range between -200 nT for magnetic low and 200 nT for magnetic high. However, the use of MATLAB is not to displace Oasis Montaj geosoftware but to give more scientific meaning to the automation of the filtering techniques used in Oasis.

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Bongiolo, Alessandra De Barros e. Silva, Francisco José Fonseca Ferreira, André Virmond Lima Bittencourt, and Eduardo Salamuni. "CONNECTIVITY AND MAGNETIC-STRUCTURAL COMPARTMENTALIZATION OF THE SERRA GERAL AND GUARANI AQUIFER SYSTEMS IN CENTRAL STATE OF PARANÁ (PARANÁ BASIN, BRAZIL)." Revista Brasileira de Geofísica 32, no. 1 (March 1, 2014): 141. http://dx.doi.org/10.22564/rbgf.v32i1.402.

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ABSTRACT. Recent research projects on the Guarani Aquifer System (GAS-granular), Paraná Basin, Brazil, have been evaluating the tectonic control and its hydrogeological potential, flow patterns, chemical properties and environmental protection aspects.One of this projects is the present research that has investigated a structured area in central State of Paraná of about 23,000 km2, delimited by coordinates 24◦00’S and 25◦00’S, 51◦00’W and 53◦00’W. The study involves Geographic Information System (GIS) integration of aeromagnetic, geological and structural characterization of lineaments based on Digital Elevation Model (DEM) and Landsat images, hydrogeological and hydrochemical data. Basaltic flows and diabase dikes (NW-SE) of the Serra Geral Formation (Lower Cretaceous) predominate in the studied area. These rocks correspond to the overlying Serra Geral Aquifer System (SGAS-fractured). The purpose of the study is to investigate the structural control on both flow and chemism of SGAS groundwater and also to identify fractures that might represent hydraulic connectivity zones to the underlying GAS. Processing and interpretation of aeromagnetic data using various techniques, useful for enhancing shallow sources, and integration with further remote sensing and geological data, allowed to outline the regional structural framework, which is characterized by a mosaic of tectonic blocks delimited by NW-SE (diabase dykes) and NE-SW (Paraná Basin basement) structures. This magnetic-structural framework was compared with the spatial distribution of hydrogeological and hydrochemical parameters. The integrated interpretations made it possible to recognize the structural control on hydrogeology and hydrochemistry of the SGAS and SAG. The results, presented in a georeferenced map, show the main zones of confinement and/or connection of SGAS and GAS. Keywords: Guarani Aquifer System, Serra Geral Aquifer System, Paran´a Basin, hydraulic connection, aeromagnetometry. RESUMO. Projetos recentes de pesquisa no Sistema Aquífero Guarani (SAG-granular), Bacia do Paraná, Brasil, têm avaliado o controle tectônico e seu potencial hidrogeológico, padrões de fluxo, propriedades químicas e aspectos de proteção ambiental. Um destes projetos é a presente pesquisa, a qual investigou uma área estruturada na região central do Estado do Paraná, delimitada pelas coordenadas 24◦00’S e 25◦00’S, 51◦00’W e 53◦00’W, com aproximadamente 23.000 km2. O estudo envolve integrações em Sistema de Informações Geográficas (SIG) de dados aeromagnéticos, geológicos, estruturais Modelo Digital de Elevação (MDE) e imagens Landsat, hidrogeológicos e hidroquímicos. Lavas basálticas e diques de diabásio (NW-SE) da Formação Serra Geral (Cretáceo Inferior) predominam na área estudada. Estas rochas correspondem ao Sistema Aquífero Serra Geral (SASG-fraturado), sobrejacente. O objetivo do estudo ´e investigar o controle estrutural do fluxo e do quimismo das águas subterrâneas do SASG e identificar também fraturas que possam representar zonas de conexão hidráulica com o SAG subjacente. Processamentos e interpretações de dados aeromagnéticos, a partir de várias técnicas, e a integração com dados de outros sensores remotos e geológicos permitiram a composição de um arcabouço estrutural regional, o qual é caracterizado por um mosaico de blocos tectônicos limitados por estruturas NW-SE (diques de diabásio) e NE-SW (embasamento da Bacia do Paraná). Este novo arcabouço magnético-estrutural foi comparado com a distribuição espacial dos parâmetros hidrogeológicos e hidroquímicos. A interpretação integrada permitiu reconhecer o controle estrutural da hidrogeologia/hidroquímica dos SASG e SAG. Os resultados, apresentados em um mapa georreferenciado, mostram as principais zonas de confinamento e/ou conexão dos SASG e SAG. Palavras-chave: Sistema Aquífero Guarani, Sistema Aquífero Serra Geral, Bacia do Paraná, conexão hidráulica, aeromagnetometria.

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Florio, Giovanni, Salvatore Passaro, Giovanni de Alteriis, and Federico Cella. "Magnetic Anomalies of the Tyrrhenian Sea Revisited: A Processing Workflow for Enhancing the Resolution of Aeromagnetic Data." Geosciences 12, no. 10 (October 10, 2022): 377. http://dx.doi.org/10.3390/geosciences12100377.

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We propose a processing workflow to enhance the information content of aeromagnetic data. Our workflow is based on the downward continuation and subsequent L-transform of magnetic data. This workflow returns a map showing single highs, which correspond to the location of magnetic bodies, and does not need any a priori information about the source magnetization. We validated our workflow using the aeromagnetic anomalies of the Tyrrhenian Sea (Italy), by a comparison of the reprocessed aeromagnetic anomalies with high-resolution shipborne magnetic data in three selected areas. Through this comparison, we show that the proposed processing workflow of aeromagnetic data leads to more accurate interpretative results. Our results indicate that, in areas where higher resolution data are lacking, the reprocessing of aeromagnetic data according to our workflow may be as decisive as to suggest changes to their previous interpretations or, at least, useful for highlighting areas of special interest, deserving to be magnetically explored by a dedicated high-resolution shipborne survey.

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Ridsdill‐Smith, T. A., and M. C. Dentith. "The wavelet transform in aeromagnetic processing." GEOPHYSICS 64, no. 4 (July 1999): 1003–13. http://dx.doi.org/10.1190/1.1444609.

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The discrete wavelet transform (DWT) provides an effective and efficient alternative to traditional Fourier and spatial‐convolution processing techniques in the enhancement of aeromagnetic data. Standard operators such as horizontal and vertical derivatives, integrals of any order, and the Hilbert transform can be diagonalized in the wavelet domain, leading to an efficient algorithm. The DWT preserves the spatial localization of the components of the signal, allowing for intelligent discrimination between noise and signal in a given frequency range. This, for example, allows for more accurate calculation of higher order derivatives from noisy signals than is possible with conventional techniques. Additional accuracy can be gained by using a cycle‐spinning algorithm to minimize local artifacts from the DWT denoising procedure.

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Rajagopalan, Shanti, and Peter Milligan. "Image Enhancement of Aeromagnetic Data using Automatic Gain Control." Exploration Geophysics 25, no. 4 (December 1994): 173–78. http://dx.doi.org/10.1071/eg994173.

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Ayigun, Sunday, K. Y. Hamid, and Omoniyi O. Titilola. "Review: Spectral Analysis of Aeromagnetic Data Interpretation." International Research Journal of Pure and Applied Physics 9, no. 1 (January 15, 2022): 1–11. http://dx.doi.org/10.37745/irjpap.13/vol9n1111.

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Spectral analysis of aeromagnetic data interpretation method is a vital tool in the field of geology and geophysics for solid minerals, groundwater, hydrocarbon and geothermal energy exploration. Human existence depends on availability of mineral and their explorations for daily activities in every part of the world. In order to reduce the scarcity of minerals and problems associated with minerals exploration, this paper reviews shed more light on source of data acquisition, data processing and interpretation in respect to the subject matter. Two case studies were considered, the first case study was on the spectral analysis method of aeromagnetic data interpretation in Longuda Plateau and its environs in Adamawa state North Eastern Nigeria. The data of the study area was divided into 16 x16 data points; the data was subjected to 2D Fourier transformation. After the spectral analysis the depth to magnetic sources were discovered ranging from 1900 m to 2620 m at the basement and shallow depth was ranging from 512 m to 670 m magnetic sources. The second case study was on magnetic data processing for hydrocarbon exploration in the Pannonian Basin, Yogoslavia, from the magnetic data analysis, hydrocarbon potential zones were identified.

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Gregotski, Mark E., Olivia Jensen, and Jafar Arkani‐Hamed. "Fractal stochastic modeling of aeromagnetic data." GEOPHYSICS 56, no. 11 (November 1991): 1706–15. http://dx.doi.org/10.1190/1.1442983.

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We present a convolutional linear data model for the processing of aeromagnetic data. The model assumes that the data derive from the superposition of a deterministic system function and a stochastic innovation process. The two‐dimensional system function is described by a four‐pass autoregressive (AR) filtering procedure and is radially symmetric. The innovation process represents the distribution of near‐surface magnetic sources and is modeled as a spectrally self‐scaling (i.e., fractal) noise. The appropriate fractal noise is determined by examining aeromagnetic power spectra from various areas of the Canadian Shield. The AR coefficients of the system are determined using an iterative deconvolution procedure. For computational convenience, we make the traditional assumption of a spectrally white innovation, but modify the data prior to its deconvolution by prewhitening the assumed fractal innovation. The recovered system function is then removed from the original data in order to produce the fractal stochastic surface. This deconvolution technique is applied to two aeromagnetic maps from northeastern Ontario, Canada and is shown to be effective in delineating lithologies and enhancing magnetic field anomalies. We propose a particular statistical description of near‐surface magnetic sources for modeling aeromagnetic data in “shield‐type” geologic environments.

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Yu, Ping, Fengyi Bi, Jian Jiao, Xiao Zhao, Shuai Zhou, and Zhenning Su. "An Aeromagnetic Compensation Algorithm Based on a Residual Neural Network." Applied Sciences 12, no. 21 (October 24, 2022): 10759. http://dx.doi.org/10.3390/app122110759.

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Aeromagnetic compensation is a crucial step in the processing of aeromagnetic data. The aeromagnetic compensation method based on the linear regression model has poorer fitting capacity than the neural network aeromagnetic compensation algorithm. The existing gradient updating neural network-based aeromagnetic compensation algorithm is subject to the problem that the gradient disappears during the backpropagation process, resulting in poor fitting ability and affecting aeromagnetic compensation accuracy. In this paper, we propose a neural network compensation algorithm with strong fitting ability: residual backpropagation neural network (Res-bp). The algorithm realizes the cross-layer propagation of the gradient through a residual connection so that the network not only preserves the original information but also acquires additional information during training, successfully solving the problem of gradient disappearance and boosting the network’s fitting capacity. The algorithm is applied to the data collected by unmanned aerial vehicles (UAVs) to verify its effectiveness. The results show that the improvement ratio is improved compared with the traditional neural network, demonstrating that the algorithm has a significant compensation effect on aeromagnetic interference and improves the quality of aeromagnetic data.

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Zhou, Shuai, Changcheng Yang, Zhenning Su, Ping Yu, and Jian Jiao. "An Aeromagnetic Compensation Algorithm Based on Radial Basis Function Artificial Neural Network." Applied Sciences 13, no. 1 (December 22, 2022): 136. http://dx.doi.org/10.3390/app13010136.

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Aeromagnetic exploration is a magnetic exploration method that detects changes of the earth’s magnetic field by loading a magnetometer on an aircraft. With the miniaturization of magnetometers and the development of unmanned aerial vehicles (UAV) technology, UAV aeromagnetic surveying plays an increasingly important role in mineral exploration and other fields due to its advantages of low cost and safety. However, in the process of aeromagnetic measurement data, due to the ferromagnetic material of the aircraft itself and the change of flight direction and attitude, magnetic field interference will occur and affect the measurement of the geomagnetic field by the magnetometer. The work of aeromagnetic compensation is to compensate for this part of the magnetic interference and improve the magnetic measurement accuracy of the magnetometer. This paper focused on the problems of UAV aeromagnetic survey data processing and improved the accuracy of UAV based aeromagnetic data measurement. Based on the Tolles–Lawson model, a numerical simulation experiment of magnetic interference of UAV-based aeromagnetic data was carried out, and a radial basis function (RBF) artificial neural network (ANN) algorithm was proposed for the first time to compensate the aeromagnetic data. Compared with classical backpropagation (BP) ANN, the test results of the synthetic data and real measured magnetic data showed that the RBF-ANN has higher compensation accuracy and stronger generalization ability.

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Shobha, C., T. Geeta Prasanna, K. Nirmala, K. Renuka Reddy, B. Lakshmi, K. J. Hebbar, M. Suryanarayana, M. V. V. Kamaraju, and A. Bhattacharya. "A package for digital processing and automatic contouring of aeromagnetic data." Journal of the Indian Society of Remote Sensing 22, no. 2 (June 1994): 93–102. http://dx.doi.org/10.1007/bf03023879.

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Mohamed, Ahmed, Mohamed Abdelrady, Fahad Alshehri, Mohammed Atef Mohammed, and Ahmed Abdelrady. "Detection of Mineralization Zones Using Aeromagnetic Data." Applied Sciences 12, no. 18 (September 9, 2022): 9078. http://dx.doi.org/10.3390/app12189078.

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Every day, mining corporations grow and develop over Egypt’s Eastern Desert in search of gold, silver, and other metals. Mineral resources in Egypt are a powerful tool for increasing national income. In this study, we are interested in mineral exploration, such as gold and porphyry deposits, using aeromagnetic data, applying various processing techniques such as First Vertical Derivative, Total Horizontal Gradient, Analytical Signal, Tilt Derivative, and the center of exploration targeting (CET). The study area is located at the Central Eastern Desert, which includes the Barramiya, Abu Marwa, and Abu Mireiwah regions. The analysis of the delineated structural trends shows that the N–S, NW–SE, and NE–SW are the most effective directions for managing deposits in the investigated area. A minor trend is also shown in the E–W direction and corresponds to the alteration zones reported by geology and prior investigations. Mineralization zones occur most frequently at the contact between ophiolitic serpentinite, sediments, and other rock types. This study intends to add more about the use of the recently developed technology of CET grid analysis for mineral exploration and structural interpretation across the Central Eastern Desert. The CET porphyry analysis map shows locations where several occurrences of porphyry deposits are probable. The newly discovered spots are similar to the area’s usual deposit sites. This study proves that aeromagnetic data are significant in mineral exploration since they are useful for the discovery of the structure and shear zones controlling the mineralization zones.

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Rigoti, Augustinho, Antonio L. Padilha, F. H. Chamalaun, and Nalin B. Trivedi. "Effects of the equatorial electrojet on aeromagnetic data acquisition." GEOPHYSICS 65, no. 2 (March 2000): 553–58. http://dx.doi.org/10.1190/1.1444750.

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In recent years, considerable advances have taken place in aeromagnetic surveying. These improvements involved data acquisition (instruments and survey design), processing, and interpretation. In addition to improved spatial resolution, the high‐resolution aeromagnetics, as applied to oil exploration, attempts to resolve very low amplitude (1 nT or even subnanotesla) magnetic features (Paterson and Reeves, 1985). These features are caused by weak intra‐sedimentary magnetic sources of magnetite and pyrrhotite, which could have been formed as a result of hydrocarbon seepage (e.g., Reynolds et al., 1990, 1991). For such small spatial variations to be meaningful, it is required that similar temporal and spatial variations due to external sources be corrected accordingly.

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Ashwini, C. P., and B. M. Divya. "Medicine Image Data Abstraction Using Image Processing." Journal of Computational and Theoretical Nanoscience 17, no. 9 (July 1, 2020): 4103–5. http://dx.doi.org/10.1166/jctn.2020.9026.

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In order to show signs of improvement recuperation and maintain a strategic distance from any reactions it is significant that the patient should take right drug for the affliction is they are enduring with. Medication data on names is a noteworthy wellspring of learning for patients. This is the significant part of prescription however we are discovering numerous cases wherein the incorrect data about the medication may make terrible effects on the individuals and will in general broaden numerous issues as opposed to decreasing the ailment. The fundamental explanation behind this, is absence of data about the medication to the patient and some being ignorant or mind conviction on the medications. In order to defeat this issue medicine data abstraction using image processing is an application which causes you to see the medication dependent on the manifestations to which the prescription is to be utilized at anyplace, whenever, through your cell phone. It encourages you to get the data of the drug by simply sitting at your home and snapping the photo of the medication.

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Tucker, D. H., I. G. Hone, D. Downie, A. Luyendyk, K. Horsfall, and V. Anfiloff. "Aeromagnetic regional survey of onshore Australia." GEOPHYSICS 53, no. 2 (February 1988): 254–65. http://dx.doi.org/10.1190/1.1442460.

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The Australian Bureau of Mineral Resources (BMR) is responsible for the National Airborne Magnetic Database. This data base consists of results from approximately 3 500 000 line‐km of regional survey flying carried out over 35 years, recording total magnetic intensity. The magnetic data base is one of the most important geophysical data bases for Australia and is used extensively by the minerals and petroleum exploration industries. First‐pass coverage of onshore Australia is aimed for completion in 1992. This coverage contains data from surveys with a wide range of specifications, resulting in a wide range of data quality; some of the areas covered by poorer quality data may be reflown later. For the most part, the intention has been to acquire data at a continuous ground clearance of 150 m and with a line spacing of 1500 m. However, over some sedimentary basins, the line spacing is in excess of 3200 m. New color and grey‐scale (image processed type) digital magnetic maps (pixel maps) are in preparation; these will supersede the 1976 digital magnetic map of Australia, which was gridded on a 1.2 minute mesh (2000 m) mostly by digitizing contours on maps. The new map, produced from flight‐line data, will have a grid size of 0.25 minutes. Initially, a series of maps will be produced with each one covering a block of 4 degrees latitude by 6 degrees longitude, coinciding with standard 1 : 1 000 000 map sheets. An example included for the Adelaide 1 : 1 000 000 map sheet in Southern Australia shows a dramatic increase in the number of anomalies over those that were evident in earlier contour presentations.

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de Miranda, Fernando Pellon, Anne E. McCafferty, and James V. Taranik. "Reconnaissance geologic mapping of a portion of the rain‐forest‐covered Guiana Shield, Northwestern Brazil, using SIR-B and digital aeromagnetic data." GEOPHYSICS 59, no. 5 (May 1994): 733–43. http://dx.doi.org/10.1190/1.1443631.

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This paper documents the result of an integrated analysis of spaceborne radar (SIR-B) and digital aeromagnetic data carried out in the heavily forested Guiana Shield. The objective of the research is to interpret the geophysical data base to its limit to produce a reconnaissance geologic map as an aid to ground work planning in a worst‐case setting. Linear geomorphic features were identified based on the interpretation of the SIR-B image. Digital manipulation of aeromagnetic data allowed the development of a color‐shaded relief map of reduced‐to‐pole magnetic anomalies, a terrace‐magnetization map, and a map showing the location of maximum values of the horizontal component of the pseudogravity gradient (magnetization boundary lines). The resultant end product was a reconnaissance geologic map where broad terrane categories were delineated and geologic faults with both topographic and magnetic expression were defined. The availability of global spaceborne radar coverage in the 1990s and the large number of existing digital aeromagnetic surveys in northwestern Brazil indicate that this approach can be potentially useful for reconnaissance geologic mapping elsewhere in the Guiana Shield.

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Liu, Yan-Xu, Wen-Yong Li, Zhi-Yuan Liu, Jia-Wei Zhao, An-Qi Cao, Shan Gao, Li-Jie Wang, and Cheng Yang. "Occurrence Characteristics of Magnetite and Aeromagnetic Prospecting Northeast of Hebei Province." Minerals 12, no. 9 (September 14, 2022): 1158. http://dx.doi.org/10.3390/min12091158.

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The occurrence characteristics of magnetite and the methods to quickly and effectively explore are important topics for ore prospecting in the new era. Taking northeast of Hebei Province of China as an example, this article aimed at an important strategic mineral of magnetite, then discussed its distribution characteristics and aeromagnetic exploration methods of it. First of all, we discuss the occurrence characteristics of sedimentary metamorphic and magmatic magnetite. Then, using the latest high-precision aeromagnetic data, combined with the geological outcrops, known iron deposits, ground magnetic surveys, and verification, we studied the relationship between the aeromagnetic anomalies and iron deposits through potential field conversion processing of the reduction to the pole, vertical derivative, upward continuation and residual anomaly, and the forward modeling and inversion methods of 2.5 D optimization fitting. Next, we summarize the metallogenic conditions and attributes of aeromagnetic prospecting and make magnetite predictions. In addition, it has suitable magnetite prospecting potential in the Laochenjia, Dabai, Jiuwuying, Beierying, Sidaogoumen, and Wuyingzi aeromagnetic anomaly regions. In conclusion, these regions have aeromagnetic anomalies with high amplitudes, large scales, and favorable metallogenic backgrounds for magmatic rocks, strata, and structures caused by concealed magnetite. In addition, they have great prospecting potential. Eventually, we hope this research method in this article can provide a reference for magnetite exploration in other areas with similar geological conditions.

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Kurniawan, Hendra, Melda Agarina, and Suhendro Yusuf Irianto. "Image Processing: Capturing Student Attendance Data." INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY 16, no. 7 (October 25, 2017): 7002–9. http://dx.doi.org/10.24297/ijct.v16i7.6390.

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Role of the student attendance record is very important in the primary, secondary, and tertiary education. The purpose of this record is monitoring student activity in the teaching and learning process and regarded as one of the important learning assessments. Moreover, a data processing for recording the student attendance is currently done in various ways such as fingerprint, radio frequent identification (RFID), facial recognition system, android-based application, and others. However, many conventional ways (i.e., using paper-based system) are still used, especially in Indonesia. This is because several universities still rarely have enough funds for developing innovative systems. In this research, the image processing application for capturing student attendance data was built. The objective of this research was to provide an efficient alternative to monitor student activities in teaching and learning process. The image processing produced the information related to student attendance by scanning the attendance file through jpg/jpeg using learning vector quantization (LVG) as the process model.

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Earl Barnes, W., and Earl E. Gose. "Functional image data acquisition and processing." Seminars in Nuclear Medicine 17, no. 1 (January 1987): 58–71. http://dx.doi.org/10.1016/s0001-2998(87)80007-7.

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Lee, Hyun-Ho. "Image Processing of GPR Detection Data." Journal of the Korea institute for structural maintenance and inspection 20, no. 4 (July 1, 2016): 104–10. http://dx.doi.org/10.11112/jksmi.2016.20.4.104.

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Narayanan, P. J., and Larry S. Davis. "Replicated data algorithms in image processing." CVGIP: Image Understanding 56, no. 3 (November 1992): 351–65. http://dx.doi.org/10.1016/1049-9660(92)90047-7.

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Ibarra-Castanedo, C., D. González, M. Klein, M. Pilla, S. Vallerand, and X. Maldague. "Infrared image processing and data analysis." Infrared Physics & Technology 46, no. 1-2 (December 2004): 75–83. http://dx.doi.org/10.1016/j.infrared.2004.03.011.

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Rejl, J., S. Saic, and K. Dědáček. "Processing of aerogeophysical data by PERICOLOR image processing system." Surveys in Geophysics 12, no. 6 (November 1991): 507–14. http://dx.doi.org/10.1007/bf01961108.

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Chouhan, Preeti, and Mukesh Tiwari. "Image Retrieval Using Data Mining and Image Processing Techniques." IJIREEICE 3, no. 12 (December 15, 2015): 53–58. http://dx.doi.org/10.17148/ijireeice.2015.31212.

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Xia, Jianghai, William E. Doll, Richard D. Miller, T. Jeffrey Gamey, and Abraham M. Emond. "A moving hum filter to suppress rotor noise in high-resolution airborne magnetic data." GEOPHYSICS 70, no. 4 (July 2005): G69—G76. http://dx.doi.org/10.1190/1.1990216.

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A unique filtering approach is developed to eliminate helicopter rotor noise. It is designed to suppress harmonic noise from a rotor that varies slightly in amplitude, phase, and frequency and that contaminates aeromagnetic data. The filter provides a powerful harmonic noise-suppression tool for data acquired with modern large-dynamic-range recording systems. This three-step approach — polynomial fitting, bandpass filtering, and rotor-noise synthesis — significantly reduces rotor noise without altering the spectra of signals of interest. Two steps before hum filtering — polynomial fitting and bandpass filtering — are critical to accurately model the weak rotor noise. During rotor-noise synthesis, amplitude, phase, and frequency are determined. Data are processed segment by segment so that there is no limit on the length of data. The segment length changes dynamically along a line based on modeling results. Modeling the rotor noise is stable and efficient. Real-world data examples demonstrate that this method can suppress rotor noise by more than 95% when implemented in an aeromagnetic data-processing flow.

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Skilbrei, Jan Reidar, and Ola Kihle. "Display of residual profiles versus gridded image data in aeromagnetic study of sedimentary basins: A case history." GEOPHYSICS 64, no. 6 (November 1999): 1740–47. http://dx.doi.org/10.1190/1.1444679.

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High‐pass filtered aeromagnetic profiles from the Mid‐Norwegian continental shelf, displayed as shaded relief versions of color stripes, provide a lucid picture of sedimentary layering and structure not easily displayed by proper application of modern enhancement techniques to images of the gridded aeromagnetic data. We show that when the aim is to analyze anomalies related to sedimentary features, it is more useful to study shaded relief versions of the profile data than to study digitally enhanced images of high‐pass filtered or calculated gradient data; a reason for this is probably the loss of high‐wavenumber, very low amplitude, information in the gridding process. The reprocessed data sets reveal anomaly patterns that are interpreted to originate from the following magnetic sources: (1) Quaternary overburden and bathymetric features, (2) magnetic sedimentary rocks, the subcropping sedimentary rock units, (3) magnetic basement in the structural highs and in the coastal zone, and (4) igneous intrusives at relatively deep levels within sedimentary basins. West of the basement rocks along the coast, the subcropping wedge of Mesozoic to Tertiary sediments is characterized by a distinct set of subparallel anomalies. Also, sedimentary layering within the Tertiary can be resolved. Short to intermediate wavelength anomalies correlate with the Late Jurassic faults of the Halten Terrace.

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Holden, Eun-Jung, Jason C. Wong, Peter Kovesi, Daniel Wedge, Mike Dentith, and Leon Bagas. "Identifying structural complexity in aeromagnetic data: An image analysis approach to greenfields gold exploration." Ore Geology Reviews 46 (August 2012): 47–59. http://dx.doi.org/10.1016/j.oregeorev.2011.11.002.

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Gruzdev, R. "Magnetic survey – ground technology, aeromagnetic survey on aircraft and unmanned aerial vehicles: a comparative analysis of the results (on the example of Eastern Transbaikalia)." Transbaikal State University Journal 26, no. 8 (2020): 6–15. http://dx.doi.org/10.21209/2227-9245-2020-26-8-6-15.

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The use of unmanned aerial vehicles (UAVs) in geophysical work is becoming a very popular area in the field of modern geological exploration. The advantage of unmanned systems is the optimal ratio of the quality of research results with a significant increase in work productivity and a decrease in cost. In this regard, the improvement of field techniques and the processing of UAV materials is of particular interest for exploration. On the subject, there are a number of unresolved issues that have been revealed to some extent as a result of the author’s comparison of ground-based magnetic exploration and aeromagnetic survey data. The purpose of the study was to assess the possibility of a full-fledged replacement of ground magnetic exploration work for aeromagnetic survey using unmanned aerial vehicles. The comparison of different types of magnetic survey is relevant, since on the basis of the actual material, the possibility of using an alternative more productive method – aeromagnetic survey using modern UAVs – instead of traditional expensive ground-based magnetic exploration works is analyzed. To compare the results of the studies, actual material obtained from field work on an area of 13,4 km2 was used. Based on the databases, maps of anomalous magnetic field and graphs on several geophysical profiles are built. Results of magnetic survey in air and ground versions are analyzed; correlation relationships between data of ground pedestrian magnetic survey and aeromagnetic system on An-3 and UAV aircraft are established. Based on the results of the study, correlation and determination coefficients were obtained, which indicate that geophysical methods on UAVs adequately occupy their place between classical aerogeophysics and ground-based pedestrian survey. Moreover, aeromagnetic survey using UAVs is able to replace pedestrian magnetic exploration during work at the same heights. Based on the results of the study, methodological recommendations for the production of aeromagnetic survey on UAVs were compiled

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Zhang, Sheng, Xiao Hong Meng, and Ya Ning Liu. "An Interpolation Method for Data Containing Distortions and its Application to Aeromagnetic Data Preprocessing." Applied Mechanics and Materials 644-650 (September 2014): 1543–46. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.1543.

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Nowadays, continuous sampling data have been widely used in the research field. However, many unpredictable distortion data points, caused by varying reasons, appear in the raw data randomly. Therefore, removing distortion data points are obligatory for raw data processing. The conventional method is the artificial recognition method, which has serious problems when applied to large volumes of data. Another way is the filtering method, which is limited by application conditions, has a bad influence on valid data what people do not expect. In this paper, we proposed an effective interpolation method to remove the distortion point. This method based on the assumption that changes between adjacent points in continuous sampling data are limited. The distortions can be recognized from the magnitude and the change rate and removed. At last, the polynomial interpolation method is used to obtain the final result. Such method has been used in the preprocessing of aeromagnetic data and gets a good result.

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Aina, Oni Olubukola, Ahzegbobor P. Aizebeokhai, and Boyo Henry Oritsemamididasan. "Analysis of aeromagnetic filtering techniques in locating the primary target in sedimentary terrain: A review." Open Physics 19, no. 1 (January 1, 2021): 912–20. http://dx.doi.org/10.1515/phys-2021-0045.

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Abstract This article analyzes some aeromagnetic filtering techniques for mitigating deceptive geophysical conceptions that may result in a distorted range of geological information from aeromagnetic data. The implication of using the aeromagnetic method, data processing, and enhancement to distinguish sediment-produced anomalies was considered. Two methods to locate buried faults in aeromagnetic data were compared: Edge and fault detection were considered using the magnetic contrast and horizontal gradient methods, whereas rapid depth estimation was considered using the Euler deconvolution method and Signum method. The general challenge to find the magnetic anomaly depth and delineate edges relies on geophysical filtering techniques discussed in order to maintain its geological relevance. The magnetic-contrast layer model signatures help clarify the existence of intra-sedimentary faults. The horizontal gradient approach relative to other derivative methods has better noise stability and fast adaptation to grids without modifying parameters. However, the Signum transform (ST) approach offers a more special solution in depth estimation than the Euler’s deconvolution approach whose solution relies on the required choice of default shape parameters and windows. The Euler deconvolution procedure may not be able to detect structures found by the ST approach and vice versa. As a result, these techniques may be used in conjunction with one another during analysis, as complementary interpretation tools. This review will however aid in the analysis of information used as a criterion for determining faults using various analytical techniques like ST or Euler deconvolution.

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Sakauchi, Masao. "Special Issue Image Processing. 3. New Application of Image Processing. 3-6 Image and Multimedia Data-base." Journal of the Institute of Television Engineers of Japan 46, no. 11 (1992): 1474–79. http://dx.doi.org/10.3169/itej1978.46.1474.

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Mehraj, Nadiya, and Harveen Kour. "Data Processing Through Image Processing using Gaussian Minimum Shift Keying." International Journal of Trend in Scientific Research and Development Volume-2, Issue-6 (October 31, 2018): 977–81. http://dx.doi.org/10.31142/ijtsrd18819.

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Ono, Kiyonobu, Makoto Maruya, Takashi Fujimura, Tsunekazu Kimura, and Minoru Murata. "3-2. Satellite Image Data Processing Techniques." Journal of The Institute of Image Information and Television Engineers 66, no. 6 (2012): 465–69. http://dx.doi.org/10.3169/itej.66.465.

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Temma, T., M. Iwashita, K. Matsumoto, H. Kurokawa, and T. Nukiyama. "Data flow processor chip for image processing." IEEE Transactions on Electron Devices 32, no. 9 (September 1985): 1784–91. http://dx.doi.org/10.1109/t-ed.1985.22198.

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Fitzke, F. W., D. P. Crabb, A. I. McNaught, D. F. Edgar, and R. A. Hitchings. "Image processing of computerised visual field data." British Journal of Ophthalmology 79, no. 3 (March 1, 1995): 207–12. http://dx.doi.org/10.1136/bjo.79.3.207.

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Smigiel, Eddie, Emmanuel Alby, and Pierre Grussenmeyer. "TLS data denoising by range image processing." Photogrammetric Record 26, no. 134 (June 2011): 171–89. http://dx.doi.org/10.1111/j.1477-9730.2011.00631.x.

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Hongian, You, Liu Schaochuang, and Li Shukai. "Data processing technology of airborne 3D image." Geo-spatial Information Science 4, no. 3 (January 2001): 62–67. http://dx.doi.org/10.1007/bf02826926.

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Journal articles on the topic 'Aeromagnetic data image processing'

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