Journal articles: 'Structural Geophysics Geophysics'

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Jessell, M. W., J. P. Cull, R. K. Valenta, A. Geiro, and G. Jung. "Structural Geophysics." Exploration Geophysics 24, no. 3-4 (September 1993): 599–602. http://dx.doi.org/10.1071/eg993599.

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Betts, Peter. "Structural geophysics: Geological principles applied to geophysical data Minerals keynote paper." ASEG Extended Abstracts 2015, no. 1 (December 2015): 1. http://dx.doi.org/10.1071/aseg2015ab112.

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Mutton, Andrew J. "The application of geophysics during evaluation of the Century zinc deposit." GEOPHYSICS 65, no. 6 (November 2000): 1946–60. http://dx.doi.org/10.1190/1.1444878.

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During the period 1990 to 1995, experimental programs using high‐resolution geophysics at several Australian operating mines and advanced evaluation projects were undertaken. The primary aim of those programs was to investigate the application of geophysical technology to improving the precision and economics of the ore evaluation and extraction processes. Geophysical methods used for this purpose include: 1) borehole geophysical logging to characterize ore and rock properties more accurately for improved correlations between drill holes, quantification of resource quality, and geotechnical information. 2) imaging techniques between drill holes to map structure directly or to locate geotechnical problems ahead of mining. 3) high‐resolution surface methods to map ore contacts and variations in ore quality, or for geotechnical requirements. In particular, the use of geophysics during evaluation of the Century zinc deposit in northern Australia demonstrated the potential value of these methods to the problems of defining the lateral and vertical extent of ore, quantitative density determination, prediction of structure between drill holes, and geotechnical characterization of the deposit. An analysis of the potential benefit of using a combination of borehole geophysical logging and imaging suggested that a more precise structural evaluation of the deposit could be achieved at a cost of several million dollars less than the conventional evaluation approach based on analysis from diamond drill‐hole logging and interpolation alone. The use of geophysics for the Century evaluation also provided substance to the possibility of using systematic geophysical logging of blast holes as an integral part of the ore extraction process. Preliminary tests indicate that ore boundaries can be determined to a resolution of several centimeters, and ore grade can be estimated directly to a usable accuracy. Applying this approach routinely to production blast holes would yield potential benefits of millions of dollars annually through improved timeliness and accuracy of ore boundary and quality data, decreased dilution, and improved mill performance. Although the indications of substantial benefits resulting from the appropriate and timely use of geophysics at Rio Tinto’s mining operations are positive, some challenges remain. These relate largely to the appropriate integration of the technology with the mining process, and acceptance by the mine operators of the economic value of such work. Until the benefits are demonstrated clearly over time, the use of geophysics as a routine component of evaluation and mining is likely to remain at a low level.

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Hauber, Ernst, Matthias Grott, and Peter Kronberg. "Martian rifts: Structural geology and geophysics." Earth and Planetary Science Letters 294, no. 3-4 (June 2010): 393–410. http://dx.doi.org/10.1016/j.epsl.2009.11.005.

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Luan, Pham Thanh, Le Huy Minh, Erdinc Oksum, and Do Duc Thanh. "Determination of maximum tilt angle from analytic signal amplitude of magnetic data by the curvature-based method." VIETNAM JOURNAL OF EARTH SCIENCES 40, no. 4 (September 18, 2018): 354–66. http://dx.doi.org/10.15625/0866-7187/40/4/13106.

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Imaging buried geological boundaries is one of a major objective during the interpretation of magnetic field data in Geophysics. Therefore, edge detection and edge enhancement techniques assist a crucial role on this aim. Most of the existing edge detector methods require to obtain special points such as in general the maxima of the resulting image. One of the useful tools in estimating edges from magnetic data is the tilt angle of the analytical signal amplitude due to its value slightly dependence on the direction of magnetization. In this study, the maxima of the tilt angle of analytical signal amplitudes of the magnetic data was determined by a curvature-based method. The technique is based on fitting a quadratic surface over a 3×3 windows of the grid for locating any appropriate critical point that is near the centre of the window. The algorithm is built in Matlab environment. The feasibility of the algorithm is demonstrated in two cases of synthetic data as well as on real magnetic data from Tu Chinh-Vung May area. The source code is available from the authors on request.ReferencesAkpınar Z., Gürsoy H., Tatar O., Büyüksaraç A., Koçbulut F., Piper, JDA., 2016. Geophysical analysis of fault geometry and volcanic activity in the Erzincan Basin, Central Turkey, Complex evolution of a mature pull-apart basin. Journal of Asian Earth Sciences, 116, 97-114. Beiki M., 2010. Analytic signals of gravity gradient tensor and their application to estimate source location, Geophysics, 75(6), 159-174.Blakely R. J., and Simpson R.W., 1986. Approximating edges of source bodies from magnetic or gravity anomalies, Geophysics, 51, 1494-1498.Chen An-Guo, Zhou Tao-Fa, Liu Dong-Jia, Zhang Shu, 2017. Application of an enhanced theta-based filter for potential field edge detection: a case study of the LUZONG ORE DISTRICT, Chinese Journal of Geophysics, 60(2), 203-218.Cooper G.RJ., 2014. Reducing the dependence of the analytic signal amplitude of aeromagnetic data on the source vector direction, Geophysics, 79, 55-60.Cordell L., 1979. Gravimetric Expression of Graben Faulting in Santa Fe Country and theEspanola Basin, New Mexico. In Ingersoll, R.V., Ed., Guidebook to Santa Fe Country, New Mexico Geological Society, Socorro, 59-64.Cordell L and Grauch V.J.S., 1985. Mapping Basement Magnetization Zones from Aeromagnetic Data in the San Juan Basin, New Mexico, The Utility of Regional Gravity and Magnetic Anomaly Maps, Society of Exploration Geophysicists, Tulsa, 181-197.Hsu S.K., Coppense D., Shyu C.T., 1996. High- resolution detection of geologic boundaries from potential field anomalies: An enhanced analytic signal technique, Geophysics, 61, 1947-1957.Le D.C., Application of seismic exploration methods to identify geological structural characteristics supporting for hydrocarbon potential assessment in TuChinh - Vung May basin, Ph.D. Thesis, Hanoi University of Mining and Geology.Li X., 2006. Understanding 3D analytic signal amplitude: Geophysics, 71(2), 13-16.Miller H.G. and Singh V., 1994. Potential Field Tilt a New Concept for Location of Potential Field Sources, Journal of Applied Geophysics, 32, 213-217.Nabighian M.N., 1972. The analytic signal of two-dimensional magnetic bodies with polygonal cross-section: Its properties and use of automated anomaly interpretation, Geophysics, 37, 507-517.Nguyen N.T., Bui V.N., Nguyen T.T.H., 2014. Determining the depth to the magnetic basement and fault systems in Tu Chinh - Vung May area by magnetic data interpretation, Journal of Marine Science and Technology, 14(4a), 16-25.Nguyen X.H, San T.N, Bae W., Hoang M.C, 2014. Formation mechanism and petroleum system of tertiary sedimentary basins, offshore Vietnam, Energy Sources, Part A, 36, 1634-1649.Phillips J.D., Hansen R.O. and Blakely R.J., 2007. The use of curvature in potential-field interpretation, Exploration Geophysics, 38(2), 111-119.Rao D.B., and Babu N.R., 1991. A rapid method for three-dimensional modeling of magnetic anomalies, Geophysics, 56(11), 1729-1737.Roest W.R., Verhoef J., and Pilkington M., 1992. Magnetic interpretation using the 3-D analytic signal, Geophysics, 57, 116-125.Tran N., 2017. Sediment geology of Vietnam, VNU Press.Tran T.D., Tran N., Nguyen T.H., Dinh X.T., Pham B.N., Nguyen T.T., Tran T.T.T.N., Nguyen T.H.T., 2018. The Miocenedepositional geological evolution of Phu Khanh, Nam Con Son and Tu Chinh - Vung May basins in Vietnam continental shelf, VNU Journal of Science: Earth and Environmental Sciences, 34(1), 112-135.Vo T.S., Le H.M., Luu V.H., 2005. Three-dimensional analytic signal method and its application in interpretation of aeromagnetic anomaly maps in the Tuan Giao region, Proceedings of the 4th geophysical scientific and technical conference of Vietnam, Publisher of Science and Engineering 2005.Wijns C, Perez C and Kowalczyk P, 2005, Theta map: Edge detection in magnetic data, Geophysics, 70, 39-43.

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Wang, Jun, Xiao Hong Meng, Fang Li, and Jun Jie Zhou. "Computer Application in Geosciences: Imaging of the Subsurface by Structural Coupled Inversion of Potential Field Data." Applied Mechanics and Materials 644-650 (September 2014): 2670–73. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.2670.

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With the continuing growth in influence of near surface geophysics, the research of the subsurface structure is of great significance. Geophysical imaging is one of the efficient computer tools that can be applied. This paper utilize the inversion of potential field data to do the subsurface imaging. Here, gravity data and magnetic data are inverted together with structural coupled inversion algorithm. The subspace (model space) is divided into a set of rectangular cells by an orthogonal 2D mesh and assume a constant property (density and magnetic susceptibility) value within each cell. The inversion matrix equation is solved as an unconstrained optimization problem with conjugate gradient method (CG). This imaging method is applied to synthetic data for typical models of gravity and magnetic anomalies and is tested on field data.

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Mueller, Hans J. "High-Pressure Deformation Techniques in Experimental Geophysics." Materials Science Forum 772 (November 2013): 45–49. http://dx.doi.org/10.4028/www.scientific.net/msf.772.45.

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Deformation processes have extrordinary importance for Geosciences. Mountainbuilding, i.e. orogenesis, slab subduction, continent-continent collision and penetration of the Earth’s mantle transition zone are examples of such processes. There is also a strong correlation between mineral content, phase transitions and structural properties of natural rocks. Ductile rock deformation is a typical property for Earth’s mantle conditions. Nevertheless most of experimental rock deformation was conducted under crustal conditions in the past. So, it was a revolutionary event when the first Deformation-DIA was introduced about a decade ago. Today this technique is indispensable not only for rock deformation under unextrapolated Earth’s mantle conditions but also for attenuation measurements in the seismic frequency range and attaining of lower mantle conditions in Large Volume Presses. In principle all these techniques require the installation of the high pressure device at a 3rd generation light source.

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Etgen, John, Samuel H. Gray, and Yu Zhang. "An overview of depth imaging in exploration geophysics." GEOPHYSICS 74, no. 6 (November 2009): WCA5—WCA17. http://dx.doi.org/10.1190/1.3223188.

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Prestack depth migration is the most glamorous step of seismic processing because it transforms mere data into an image, and that image is considered to be an accurate structural description of the earth. Thus, our expectations of its accuracy, robustness, and reliability are high. Amazingly, seismic migration usually delivers. The past few decades have seen migration move from its heuristic roots to mathematically sound techniques that, using relatively few assumptions, render accurate pictures of the interior of the earth. Interestingly, the earth and the subjects we want to image inside it are varied enough that, so far, no single migration technique has dominated practical application. All techniques continually improve and borrow from each other, so one technique may never dominate. Despite the progress in structural imaging, we have not reached the point where seismic images provide quantitatively accurate descriptions of rocks and fluids. Nor have we attained the goal of using migration as part of a purely computational process to determine subsurface velocity. In areas where images have the highest quality, we might be nearing those goals, collectively called inversion. Where data are more challenging, the goals seem elusive. We describe the progress made in depth migration to the present and the most significant barriers to attaining its inversion goals in the future. We also conjecture on progress likely to be made in the years ahead and on challenges that migration might not be able to meet.

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Kaftan, V. I., R. I. Krasnoperov, V. N. Tatarinov, and E. V. Vavilin. "Geoinformatics and systems analysis in geophysics and geodynamics." Физика Земли, no. 1 (March 27, 2019): 42–60. http://dx.doi.org/10.31857/s0002-33372019142-60.

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The paper is devoted to the application of geoinformatics and systems analysis methods for processing and interpretation of geospatial data in geophysics and geodynamics. The modern uses of observations with Global Navigational Satellite Systems as a main source of geospatial data are discussed. The advances in the interpretation of geomagnetic data are described and basic points of systems analysis are presented in this context. The systems analysis in geophysics and geodynamics is illustrated by the approaches to estimating and forecasting the stability of structural-tectonic blocks of the Earth’s crust aimed at geoecologically safe burial of high-level radioactive waste in the Nizhne-Kanskii granitoids massif (Krasnoyarsk krai).

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Aranda Gómez, Jorge, Vsevolod Yutsis, Edgar Juárez-Arriaga, Carlos Ortega-Obregón, Norma González-Cervantes, Gabriel Chávez-Cabello, César Francisco Ramírez-Peña, and David Ernesto Torres-Gaytán. "Reconnaissance geology and geophysics of the Mercurio structural dome, Chihuahua, Mexico." Revista Mexicana de Ciencias Geológicas 36, no. 3 (November 30, 2019): 357–77. http://dx.doi.org/10.22201/cgeo.20072902e.2019.3.1340.

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The Mercurio structural dome is a poorly exposed and complex structure located in the transitional region between the Coahuila Calcareous Platform and the San Pedro El Gallo sector of the Sierra Madre Oriental, Mexico. It is located in the State of Chihuahua, close to the limits with Coahuila and Durango, Mexico. The dome is a circular structure, ~16 km in diameter, that can be seen in air-photos, satellite images, and shaded relief maps, but that has a subtle topographic expression on the ground. As seen in the field, the most conspicuous topographic features in the area are several hills with the morphology of volcanic necks that rise up to 250 m above the surrounding terrain. The deformation fringe of the dome is a series of cuesta-like low hills, less than 30 m high, where a poorly lithified volcano-sedimentary succession (litharenites, polymictic conglomerates, and ignimbrites) is almost completely masked by desert pavement, which is mainly constituted by well-rounded calcareous clasts derived from the Mesozoic sedimentary marine rocks and by less abundant Paleogene volcanic rocks exposed in the region. Inside the dome the following units are exposed: 1) the pre-volcanic basement in a NW-trending, upright, open anticline developed in limestone of the Aurora Formation, 2) a series of hills where is exposed a succession of epiclastic and volcanic rocks, which are similar, in age and lithology, to some facies of the Ahuichila Formation, and 3) a NW-trending dike, exposed at Cerro Dinamita, which is interpreted as an offshoot of the buried subvolcanic body that created the dome. The deformation fringe around the buried intrusive has a quaquaversal array in the bedding and forms a simple monocline-like structure in the NE part of the dome. A set of SE- and NW-trending plunging folds forms the SE and SW portions of the dome, respectively. The NW part of the fringe is nearly completely masked by volcanic rocks, but there is a ~W plunging syncline in the area. Geophysical data show a broad gravimetric high in the region, and there is a distinct aeromagnetic anomaly inside the dome. The morphological expression of the dome lies just east of a NW-trending lineament of gravity and magnetic anomalies, which may be the buried portion of a normal fault shown in geologic maps of the region northwest of the studied area. Another possible cause is an alignment of buried intrusive bodies suggested by the regional aeromagnetic data, a small diorite outcrop south of Sierra El Diablo, and presence of volcanic necks in the northern portion of Sierra Los Alamos. Available geological and geophysical information was used to model a near-surface, irregular intrusive body with variable magnetic susceptibilites. This variation in susceptibilities is consistent with observed differences in rock composition in the exposed volcanic rocks and with evidence that the structure was formed by a bimodal (andesite-rhyolite) magmatic system where mixing/mingling occurred. As a whole, the set of structures is interpreted as a dome formed by forceful magma injection into a previously folded Paleogene volcano-sedimentary succession. U-Pb zircon ages were used to bracket the age of the deformation pulses registered in the rocks. Litharenites from the deformed volcano-sedimentary succession yielded an Ypresian zircon age of ~51 Ma. A tilted, lithic-rich ignimbrite collected near the top of the exposed volcano-sedimentary succession has mean age of 46.4 +0.8/-1.6 Ma, and the Cerro Dinamita dike has a mean age of 29.37 ± 0.24 Ma. Thus, the youngest pulse of Laramide deformation in the area is younger than ~46 Ma and the re-folding, associated with emplacement of the dome occurred at ~29 Ma. Detrital zircon U-Pb ages from Mercurio sandstones suggest dominant sediment sources from plutonic and/or volcanic rocks exposed along western Mexico. Likely subordinate sources are Mesozoic sedimentary rocks in northern and central Mexico. Distribution of detrital zircon U-Pb ages in the studied samples is similar to that documented in sandstones of the Difunta Group at the Parras and La Popa basins, except that older grains (>1.0 Ga), documented in the clastic rocks of these basins, are scarce in the sandstones of the Mercurio area.

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Minsley, Burke J., Nathan Leon Foks, and Paul A. Bedrosian. "Quantifying model structural uncertainty using airborne electromagnetic data." Geophysical Journal International 224, no. 1 (August 25, 2020): 590–607. http://dx.doi.org/10.1093/gji/ggaa393.

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SUMMARY The ability to quantify structural uncertainty in geological models that incorporate geophysical data is affected by two primary sources of uncertainty: geophysical parameter uncertainty and uncertainty in the relationship between geophysical parameters and geological properties of interest. Here, we introduce an open-source, trans-dimensional Bayesian Markov chain Monte Carlo (McMC) algorithm GeoBIPy—Geophysical Bayesian Inference in Python—for robust uncertainty analysis of time-domain or frequency-domain airborne electromagnetic (AEM) data. The McMC algorithm provides a robust assessment of geophysical parameter uncertainty using a trans-dimensional approach that lets the AEM data inform the level of model complexity necessary by allowing the number of model layers itself to be an unknown parameter. Additional components of the Bayesian algorithm allow the user to solve for parameters such as data errors or corrections to the measured instrument height above ground. Probability distributions for a user-specified number of lithologic classes are developed through posterior clustering of McMC-derived resistivity models. Estimates of geological model structural uncertainty are thus obtained through the joint probability of geophysical parameter uncertainty and the uncertainty in the definition of each class. Examples of the implementation of this algorithm are presented for both time-domain and frequency-domain AEM data acquired in Nebraska, USA.

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Geng, Meixia, Xiangyun Hu, Henglei Zhang, and Shuang Liu. "3D inversion of potential field data using a marginalizing probabilistic method." GEOPHYSICS 83, no. 5 (September 1, 2018): G93—G106. http://dx.doi.org/10.1190/geo2016-0683.1.

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Probabilistic inversion methods have proven effective in solving many geophysical inverse problems. Structural orientation and spatial extent information can be efficiently incorporated the probabilistic inversion by the use of parameter covariances to produce a geologically realistic model. However, the use of a single model covariance matrix, with the underlying assumption of the presence of only one type of feature (e.g., similar size, shape, and orientation) in the subsurface, limits the ability of probabilistic inversions to recover geologically sound models. An approach based on marginalizing the probabilistic inversion is presented, which makes it possible to partition the inverse domain into various zones, each of which can have its own covariance matrix depending upon the features and/or depths of the sources. Moreover, a spatial gradient weighting function is introduced to enhance or attenuate the structural complexity in different zones. Thus, sources with different shapes, sizes, depths, and densities (or magnetic susceptibilities) can be simultaneously reconstructed. The sensitivity of the solutions to uncertainties in the a priori information, including the orientation, depth, and horizontal position as well as subdivision of the inversion domain, is analyzed. We found through synthetic examples and field data that the developed inversion method was a valid tool for exploration geophysics in presence of a priori geologic information.

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Pinéo, Tercyo Rinaldo Gonçalves, Raimundo Mariano Gomes Castelo Branco, Luciano Soares Da Cunha, and Mauro Lisboa Souza. "AIRBORNE AND GROUND GEOPHYSICS APPLIED TO GROUNDWATER PROSPECTION IN HARD ROCKS IN IRAUÇUBA, CEARÁ STATE, BRAZIL." Revista Brasileira de Geofísica 31, no. 4 (December 1, 2013): 699. http://dx.doi.org/10.22564/rbgf.v31i4.347.

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ABSTRACT. This work involved geophysical prospecting techniques, remote sensing and litho-structural recognition, applied to groundwater research in a region formed by hard rocks located in Irauçuba, Ceará State, Brazil. Geophysical magnetic and electromagnetic airborne data compiled from PROASNE project (Projeto Água Subterrânea do Nordeste do Brasil ), Landsat ETM7 satellite images and electromagnetic land data, acquired in this research, were studied and allowed mapping lineaments related to geological structures, properly characterized by structural recognition on the field. The integrated analysis of geophysical and geological data, including hydrogeological information from deep wells, allowed understanding the pattern of fractures in the area, correlating the structures with the geological event responsible for their genesis and determining their hydrogeological potential. The results culminated in a structural-hydrogeological local model to be applied in areas with similar geological features. According to this model, geological brittle structures with approximate N-S direction are little penetrative and contribute to the recharge structures of WNW-ESE direction, which are the most promising for groundwater exploitation through deep wells.Keywords: groundwater in hard rocks, geophysics prospection, remote sensing. RESUMO. Este trabalho envolveu técnicas geofísicas de prospecção, sensoriamento remoto e reconhecimento lito-estrutural, aplicados à pesquisa de água subterrânea em uma região formada por rochas cristalinas, localizada no município de Iraçuba, Estado do Ceará, Brasil. Dados geofísicos magnéticos e eletromagnéticos aerotransportados compilados do projeto PROASNE (Projeto Água Subterrânea do Nordeste do Brasil), imagens do satélite LandSat ETM7 e dados eletromagn´eticos terrestres, adquiridos nesta pesquisa, foram trabalhados de forma integrada e permitiram cartografar lineamentos referentes a estruturas geol´ogicas diversas, devidamente caracterizados através de reconhecimento estrutural em atividade de campo. A análise integrada dos dados geofísicos e geológicos, incluindo informações hidrogeológicas de poços profundos, possibilitou compreender o padrão de fraturas da área, correlacionar as estruturas com o evento geológico responsável por sua gênese e determinar o potencial hidrogeológico destas estruturas. Os resultados obtidos culminaram em um modelo estrutural-hidrogeológico local, de aplicação em áreas com características geológicas similares. De acordo com o referido modelo, estruturas geológicas rúpteis de direção aproximada N-S são pouco penetrativas e tem como função principal contribuir com a recarga das estruturas de direção WNW-ESE, que são mais promissoras a explotação de água subterrânea por meio de poço tubular profundo.Palavras-chave: aquifero fissural, geofísica de prospecção, sensoriamento remoto.

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Høyer, Anne-Sophie, Ingelise Møller, and Flemming Jørgensen. "Challenges in geophysical mapping of glaciotectonic structures." GEOPHYSICS 78, no. 5 (September 1, 2013): B287—B303. http://dx.doi.org/10.1190/geo2012-0473.1.

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Glaciotectonic complexes have been recognized worldwide — traditionally described on the basis of outcrops or geomorphological observations. In the past few decades, geophysics has become an integral part of geologic mapping, which enables the mapping of buried glaciotectonic complexes. The geophysical methods provide different types of information and degrees of resolution and thus, a different ability to resolve the glaciotectonic structures. We evaluated these abilities on the basis of an integrated application of four commonly used geophysical methods: airborne transient electromagnetics, high-resolution reflection seismic, geoelectrical, and ground-penetrating radar (GPR). We covered an area of [Formula: see text] in a formerly glaciated region in the western part of Denmark. The geologic setting was highly heterogeneous with glaciotectonic deformation observed in the form of large-scale structures in the seismic and airborne transient electromagnetic data to small-scale structures seen in the GPR and geoelectrical data. The seismic and GPR data provided detailed structural information, whereas the geoelectrical and electromagnetic data provided indirect lithological information through resistivities. A combination of methods with a wide span in resolution capabilities can therefore be recommendable to characterize and understand the geologic setting. The sequence of application of the different methods is primarily determined by the gross expenditure required for acquisition and processing, e.g., per kilometer of the surveys. Our experience suggested that airborne electromagnetic data should be acquired initially to obtain a 3D impression of the geologic setting. Based on these data, areas can be selected for further investigation with the more detailed but also more expensive and time-consuming methods.

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Austin, James R., Phillip W. Schmidt, and Clive A. Foss. "Magnetic modeling of iron oxide copper-gold mineralization constrained by 3D multiscale integration of petrophysical and geochemical data: Cloncurry District, Australia." Interpretation 1, no. 1 (August 1, 2013): T63—T84. http://dx.doi.org/10.1190/int-2013-0005.1.

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Magnetite-rich iron oxide copper-gold deposits (IOCGs) are geologically and geochemically complex and present major challenges to geophysical investigation. They often sit beneath significant cover, exhibit magnetic remanence, and suffer from self-demagnetization effects. Because remanence in magnetite-bearing drill core samples is commonly overprinted by drilling, in situ natural remanent magnetization is difficult to measure accurately, and thus IOCGs cannot be modeled definitively using geophysics alone. We examined structural controls on a magnetite-rich IOCG in northwest Queensland and the relationships between structure, alteration, Fe oxides, and mineralization at core to deposit scale. Magnetite within the deposit has a multidomain structure, and thus it would commonly have an in situ magnetization parallel to the earth’s field. In contrast, pyrrhotite has a pseudosingle-domain structure and so it is the predominant carrier of stable remanence within the ore system. Geophysical lineament analyses are used to determine structural controls on mineralization, geophysical filters (e.g., analytic signal amplitude) are used to help define structural extent of the deposit, and basement geochemistry is used to map mineral footprints beneath cover. These techniques identified coincident anomalies at the intersection of north and northwest lineaments. Leapfrog™ interpolations of downhole magnetic susceptibility and Cu, Au, and Fe assay data were used to map the distribution of magnetite, copper, gold, and sulfur in 3D. The analysis revealed that Cu and Au mineralization were coupled with the magnetite net-vein architecture, but that Cu was locally enriched in the east–northeast-trending demagnetized zone. The results from this suite of geophysical, petrophysical, and geochemical techniques were integrated to constrain modeling of the Brumby IOCG. Brumby can be described as a breccia pipe sitting at the intersection of north-striking, east-dipping, and northwest-striking, southeast-dipping structures that plunges moderately to the south–southeast. The breccia pipe was overprinted by a relatively late net-vein magnetite breccia and crosscut by a later, magnetite-destructive, east–northeast-striking fault.

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Podestá, Luis, Esteban Sáez, Gonzalo Yáñez, and Felipe Leyton. "Geophysical Study and 3-D Modeling of Site Effects in Viña del Mar, Chile." Earthquake Spectra 35, no. 3 (August 2019): 1329–49. http://dx.doi.org/10.1193/080717eqs155m.

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The Maule 2010 earthquake (Mw 8.8) produced damage to several buildings throughout Central Chile. This was particularly the case in downtown Viña del Mar, where an anomalous concentration of structural damage was found in several medium-rise buildings distributed along a narrow area approximately 1 km in length. These observations suggest the possibility of a localized area of seismic amplification effects. We conducted a geophysical characterization using surface wave–based techniques and gravimetry to characterize the main dynamic properties of the soil and the depth of the basin. These data, complemented with several standard penetration test measurements, were used to develop a three-dimensional (3-D) geotechnical characterization of the area. Additionally, the cyclic behavior of predominant materials was experimentally characterized based on remolded samples. To assess complex site-amplification effects, we developed a computational 3-D model constrained by surface-wave geophysics and laboratory results, assuming a homogenous basin infill with increasing stiffness with depth. The results partially agree with damage observations and suggest an explanation related to basement shape in some areas of the modeled region.

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Fomel, Sergey, and Evgeny Landa. "Structural uncertainty of time-migrated seismic images." Journal of Applied Geophysics 101 (February 2014): 27–30. http://dx.doi.org/10.1016/j.jappgeo.2013.11.010.

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Vuong, Hoang Van, Tran Van Kha, Pham Nam Hung, and Nguyen Kim Dung. "Research on deep geological structure and forecasting of some areas with petroleum prospects in the Red river delta coastal strip according to geophysical data." Tạp chí Khoa học và Công nghệ biển 19, no. 3B (October 21, 2019): 71–89. http://dx.doi.org/10.15625/1859-3097/19/3b/14516.

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The coastal areas of the Red River Delta are the transition areas from the continent to the sea and have great mineral prospects, especially petroleum prospects. In this area, a lot of topics and projects in geology and geophysics have been conducted for many different purposes such as studying the deep structure, tectonic - geological features, seismic reflection - refraction to identify petroleum traps in the Cenozoic sediments... However there are very few studies on deep structure features, using the results of processing and meta-analysis of gravity, magnetotelluric, tectonic - geological data to detect the direct and indirect relations to the formation of structures with petroleum potential. The authors have researched, tested and applied an appropriate methodology of processing and analysis, to overcome the shortfall of gravity data as well as the nonhomogeneity in details of seismic and geophysical surveys. The obtained results are semi-quantitative and qualitative characteristics of structure of deep boundary surfaces, structural characteristics of fault systems and their distribution in the study area, calculation of the average rock density of pre-Cenozoic basement... From these results, the authors established the zoning map of the areas with petroleum potential in the Red river delta coastal strip according to geophysical data.

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Schimmrich, Steven Henry. "Exploring Geology on the World Wide Web – Geophysics, Plate Tectonics, and Structural Geology." Journal of Geoscience Education 44, no. 3 (May 1996): 317–20. http://dx.doi.org/10.5408/1089-9995-44.3.317.

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Schellart, W. P., and N. Rawlinson. "Convergent plate margin dynamics: New perspectives from structural geology, geophysics and geodynamic modelling." Tectonophysics 483, no. 1-2 (March 2010): 4–19. http://dx.doi.org/10.1016/j.tecto.2009.08.030.

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Wright, James L., and Steven R. Koehler. "North Bullion: Latest gold discovery on the Carlin Trend, Nevada." Interpretation 3, no. 2 (May 1, 2015): SL27—SL38. http://dx.doi.org/10.1190/int-2014-0187.1.

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Gold Standard Ventures Corp. highlighted in their 2014 corporate presentation that “North Bullion and Central Bullion were both gravity- and CSAMT-led discoveries.” The North Bullion gold discovery demonstrates the continued effectiveness of geophysics as applied to gold exploration on the Carlin Trend of northeast Nevada. In combination with geologic understanding and target model development, geophysics provides a cost-effective exploration tool to guide exploration drilling. A sustained, incremental program is critical to realizing the full benefit geophysics brings to the exploration effort. In a program spanning five years, 3587 gravity stations and 51.7 line-km of controlled-source audio magnetotelluric (CSAMT) data have been acquired in a multistage approach. A major structure, called the Bullion Fault Corridor (BFC), hosts two known gold deposits over an 18-km strike length. Gravity, followed up with CSAMT, defines the BFC in detail, as well as hydrothermal alteration products related to the mineralization process. Drill and geologic confirmation is integrated with the geophysics to refine interpretations and adjust ongoing survey design. Application of gravity along the Carlin Trend has been actively used as a structural mapping tool for many years. However, combining the results with CSAMT is a more recent development, particularly along the Carlin Trend.

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RONCATO, Jorge, Ana Luiza de CARVALHO ALMEIDA, Bárbara MACEDO, and Matheus OLIVEIRA. "ANÁLISE GEOFÍSICA DA REGIÃO DO RIO CONCEIÇÃO, QUADRILÁTERO FERRÍFERO, ASSOCIADOS A DADOS DE CAMPO, PETROGRÁFICOS E DE IMAGENS AÉREAS." Geosciences = Geociências 39, no. 1 (May 19, 2020): 47–63. http://dx.doi.org/10.5016/geociencias.v39i1.14613.

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The Quadrilátero Ferrífero region, located in the southeast portion of the São Francisco Craton, is one of the main metallogenic provinces in Brazil. Fieldwork, petrography, high-resolution airborne geophysics (magnetic and gamma-ray spectrometry data), and aerial images allowed us to produce a new map at the 1:25,000 scale, with important contributions in the lithotypes detailing, understanding of the geological structures and relationship between the different stratigraphic units. Interpretation of airborne geophysical data integrated with field structural and lithological observations were successfully employed in the creation of the litho-structural framework in a poorly exposed Proterozoic and Archean terrain. Airborne gamma-ray spectrometry data aided in the mapping process in areas with regolith cover including erosional ridges. The magnetic total derivative image revealed regional and local structures. In addition, our work details the units of occurrence of Rio das Velhas and Minas Supergroup. The aerial coverage of the Mindá and Santa Quitéria formations strongly increased, as well as the area of the Cauê Formation was better defined. The new geological map provides many improvements over the pre-existing maps. New lithological facies and structures were identified and others become more visible and lithologicalboundaries are refined or confirmed.

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Iasky, R. P., R. A. Young, and M. F. Middleton. "Structural Study of the Southern Perth Basin by Geophysical Methods." Exploration Geophysics 22, no. 1 (March 1991): 199–205. http://dx.doi.org/10.1071/eg991199.

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Carvalho, Diogo Luiz Órphão de, Roberta Mary Vidotti, José Oswaldo de Araújo Filho, and Paulo Roberto Meneses. "GEOLOGY, AIRBORNE GEOPHYSICS AND GROUND GRAVITY OF THE CENTRAL GRABEN OF ÁGUA BONITA, BRAZIL." Revista Brasileira de Geofísica 30, no. 4 (December 1, 2012): 483. http://dx.doi.org/10.22564/rbgf.v30i4.235.

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Há mais de meio século a utilização de dados geofísicos representa importante ferramenta auxiliar nas pesquisas em geociências. Dentre outras características, tais produtos facilitam a discriminação de feições estruturais, ajudam a caracterização de corpos geológicos em subsuperfície e permitem a delimitação de domínios geofísicos com correspondentes geológicos. O Graben de Água Bonita, localizado nos estados de Goiás e Tocantins, foi definido na metade da década de 60 do século XX como uma estrutura de 80 km por 7 km, com bordas paralelas e retilíneas de direção N35-40◦E. O conhecimento desta estrutura restringe-se ao mapeamento geológico, inexistindo dados em profundidade. O presente trabalho trata da interpretação de dados aerogeofísicos do Levantamento Geofísico Brasil-Canadá (PGBC); aquisição e interpretação de dados gravimétricos terrestres visando contribuir ao conhecimento geológico-estrutural do Graben de Água Bonita, situado no contexto do Lineamento Transbrasiliano. A interpretação qualitativa e quantitativa dos dados geofísicos e geológicos originada de modelagem 2D, sugere que o Graben de Água Bonita inclina-se para oeste, devido às baixas anomalias e ao mergulho das sequências sedimentares detríticas. Esta inclinação evidencia que o depocentro da Formação Água Bonita localiza-se a aproximadamente 4 km de profundidade a oeste do limite superficial desta Formação. ABSTRACT: For over half a century geophysical data is an important auxiliary tool used in geosciences research. Among other features, these products facilit at ethe discrimination of structural features, aid the characterization of subsurface geological bodies and allow the delimitation of areas with corresponding geophysica land geological data. The Água Bonita Graben (GAB), which straddles the border of Goiás and Tocantins states, was defined in the mid-60s as an 80-km long by 7-km wide structure, with parallel, straight borders towards N35-40◦E. This paper presents an interpretation of the geophysical data obtained by the the Geophysical Survey Brazil-Canada (Programa de Levantamentos Geofísicos Brasil-Canadá, PGBC), as well as acquisition and interpretation of ground gravity data aiming at improving the geological knowledge of the Água Bonita Graben, situated in the Transbrasilian Lineament. The PGBC geophysical data allowed the extraction of lineaments and geophysical delineation of the GAB limits. The 2D model suggests that the Água Bonita Graben leans to the west, due to the observed low gravity anomaly values and inclined detrital sedimentary sequences dipping 8◦-12◦, in the direction 300◦ to 330◦, suggesting that the depocenter of the Água Bonita Formation is near by the western edge of the graben.Keywords: ground gravity, Água Bonita Graben, Transbrasilian Lineament.

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Kong, Qingkai, Richard M. Allen, Monica D. Kohler, Thomas H. Heaton, and Julian Bunn. "Structural Health Monitoring of Buildings Using Smartphone Sensors." Seismological Research Letters 89, no. 2A (January 10, 2018): 594–602. http://dx.doi.org/10.1785/0220170111.

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Cheng, Liang, Shangxu Wang, Shengjun Li, and Yongzhen Ji. "Multi-trace nonstationary sparse inversion with structural constraints." Acta Geophysica 68, no. 3 (April 22, 2020): 675–85. http://dx.doi.org/10.1007/s11600-020-00430-3.

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Poole, Anastasia, and Phillip Bilsby. "Surface seismic for structural imaging and reservoir characterization." First Break 36, no. 1 (January 1, 2018): 69–76. http://dx.doi.org/10.3997/1365-2397.n0065.

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Seeber, L. "Structural Control of Seismicity in the Northeastern U. S." Seismological Research Letters 59, no. 4 (October 1, 1988): 313. http://dx.doi.org/10.1785/gssrl.59.4.313.

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Abstract Seismicity in the northeastern U. S. can often be correlated to preexisting structural features. This correlation is found over a wide range of scales and distinct types of correlation characterize the opposite ends of this range. Firstly, patterns of seismicity measured in tens or hundreds of kms are recognized in maps of recent epicenters from regional networks and in maps of earlier macroseismic epicenters. These patterns are characterized by epicenter bands of resolvable widths, but, within these bands, individual ruptures are often oriented at large angles to the strike of the bands. Several of these seismicity patterns can be spatially correlated to structural features in the crystalline layer of the upper crust which is the source of seismicity. These features are recognized as major lithologic boundaries or suture zones, characterized by ductile deformation without evidence for a subsequent brittle phase. Hence, these large scale features are not preexisting weaknesses reactivated in the current regime. Stress concentration derived from lithologic and rheologic contrast along the boundaries may be an important mechanism in these cases. Secondly, high resolution of aftershock zones in areas where the seismogenic layer outcrops has allowed detailed correlation between ruptures and brittle features. Two cases, one in the Grenville terrane of the craton and the other in the Manhattan Prong along the crystalline core of the Appalachians, show similar characteristics. The ruptures are small, 1.5 and 0.5 kms respectively, but their geometry is well defined by the aftershocks. Both these ruptures are associated with zones of brittle fractures that can be followed at the surface for more than 10 kms. These fracture zones are primarily recognized as topographic lineaments, concentrations of slikensided joints and sets of small en echelon faults. The aftershocks zones are parallel to the individual faults in these en echelon fault sets. The total accumulated horizontal displacement across these fracture zones is small (less than 50 to 100 meters) when compared to the rates of moment release and to the inferred pre-Cenozoic age of these fracture zones. The maximum magnitude from these fracture zones is probably controlled by the size of individual faults in the en echelon pattern, rather than by the much larger dimension of the entire fracture zone.

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Hillhouse, John W., and Michael O. McWilliams. "Application of paleomagnetism to accretionary tectonics and structural geology." Reviews of Geophysics 25, no. 5 (1987): 951. http://dx.doi.org/10.1029/rg025i005p00951.

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Mário Lopes, Gemma Musacchio, Mónica Amaral Ferrira, and Carlos Sousa Oliveira. "Foreword Special issue Empowering communities for non-structural seismic risk mitigation: the central role of communication." Annals of Geophysics 64, no. 3 (July 23, 2021): SE331. http://dx.doi.org/10.4401/ag-8714.

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This special issue of “Annals of Geophysics” concerns the dissemination of knowledge on the prevention of damage mainly due to non-structural elements during earthquakes and its practical application at houses, schools and offices by common citizens, companies and institutions. The seismic capacity of buildings and other civil engineering structures and infrastructures are object of regulations for design and construction, and in some cases also the design, fabrication and mounting of electrical and mechanical equipments. Consequently, even in strong earthquakes many collapses of buildings and infrastructures are avoided. However, with few exceptions, design procedures do not aim at avoiding seismic vibrations from being transferred to the structures, but enable the structures to resist to the effects of those vibrations

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MacDonald, William D., and Brooks B. Ellwood. "Anisotropy of magnetic susceptibility: Sedimentological, igneous, and structural-tectonic applications." Reviews of Geophysics 25, no. 5 (1987): 905. http://dx.doi.org/10.1029/rg025i005p00905.

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Stewart, Ian C. F., and David T. Miller. "Directional tilt derivatives to enhance structural trends in aeromagnetic grids." Journal of Applied Geophysics 159 (December 2018): 553–63. http://dx.doi.org/10.1016/j.jappgeo.2018.10.004.

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Akca, İrfan, and Şerif Murat Gölebatmaz. "Three-dimensional inversion of DCR data incorporating structural similarity constraint." Journal of Applied Geophysics 184 (January 2021): 104237. http://dx.doi.org/10.1016/j.jappgeo.2020.104237.

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Martinez-Landa, Lurdes, Jesús Carrera, Andrés Pérez-Estaún, Paloma Gómez, and Carmen Bajos. "Structural geology and geophysics as a support to build a hydrogeologic model of granite rock." Solid Earth 7, no. 3 (June 1, 2016): 881–95. http://dx.doi.org/10.5194/se-7-881-2016.

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Abstract. A method developed for low-permeability fractured media was applied to understand the hydrogeology of a mine excavated in a granitic pluton. This method includes (1) identifying the main groundwater-conducting features of the medium, such as the mine, dykes, and large fractures, (2) implementing this factors as discrete elements into a three-dimensional numerical model, and (3) calibrating these factors against hydraulic data . A key question is how to identify preferential flow paths in the first step. Here, we propose a combination of several techniques. Structural geology, together with borehole sampling, geophysics, hydrogeochemistry, and local hydraulic tests aided in locating all structures. Integration of these data yielded a conceptual model of the site. A preliminary calibration of the model was performed against short-term (< 1 day) pumping tests, which facilitated the characterization of some of the fractures. The hydraulic properties were then used for other fractures that, according to geophysics and structural geology, belonged to the same families. Model validity was tested by blind prediction of a long-term (4 months) large-scale (1 km) pumping test from the mine, which yielded excellent agreement with the observations. Model results confirmed the sparsely fractured nature of the pluton, which has not been subjected to glacial loading–unloading cycles and whose waters are of Na-HCO3 type.

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Hill, K. A., G. T. Cooper, M. J. Richardson, and C. J. Lavin. "Structural Framework of the Eastern Otway Basin: Inversion and Interaction Between Two Major Structural Provinces." Exploration Geophysics 25, no. 2 (June 1994): 79–87. http://dx.doi.org/10.1071/eg994079.

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Lochbühler, Tobias, Joseph Doetsch, Ralf Brauchler, and Niklas Linde. "Structure-coupled joint inversion of geophysical and hydrological data." GEOPHYSICS 78, no. 3 (May 1, 2013): ID1—ID14. http://dx.doi.org/10.1190/geo2012-0460.1.

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In groundwater hydrology, geophysical imaging holds considerable promise for improving parameter estimation, due to the generally high resolution and spatial coverage of geophysical data. However, inversion of geophysical data alone cannot unveil the distribution of hydraulic conductivity. Jointly inverting geophysical and hydrological data allows us to benefit from the advantages of geophysical imaging and, at the same time, recover the hydrological parameters of interest. We have applied a coupling strategy between geophysical and hydrological models that is based on structural similarity constraints. Model combinations, for which the spatial gradients of the inferred parameter fields are not aligned in parallel, are penalized in the inversion. This structural coupling does not require introducing a potentially weak, unknown, and nonstationary petrophysical relation to link the models. The method was first tested on synthetic data sets and then applied to two combinations of geophysical/hydrological data sets from a saturated gravel aquifer in northern Switzerland. Crosshole ground-penetrating radar (GPR) traveltimes were jointly inverted with hydraulic tomography data, as well as with tracer mean arrival times, to retrieve the 2D distribution of GPR velocities and hydraulic conductivities. In the synthetic case, incorporating the GPR data through a joint inversion framework improved the resolution and localization properties of the estimated hydraulic conductivity field. For the field study, recovered hydraulic conductivities were in general agreement with flowmeter data.

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Benedetto, A., and S. Pensa. "Indirect diagnosis of pavement structural damages using surface GPR reflection techniques." Journal of Applied Geophysics 62, no. 2 (June 2007): 107–23. http://dx.doi.org/10.1016/j.jappgeo.2006.09.001.

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Bazin, S., and A. A. Pfaffhuber. "Mapping of quick clay by electrical resistivity tomography under structural constraint." Journal of Applied Geophysics 98 (November 2013): 280–87. http://dx.doi.org/10.1016/j.jappgeo.2013.09.002.

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Zanella, Renata Ribas, Barbara Trzaskos, Luís Gustavo de Castro, and Francisco José Fonseca Ferreira. "Geophysical-structural framework of the Campo Alegre basin (Santa Catarina State, southern Brazil)." Journal of Applied Geophysics 183 (December 2020): 104189. http://dx.doi.org/10.1016/j.jappgeo.2020.104189.

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Li, Dong, Suping Peng, Rui Zhang, Yinling Guo, Yongxu Lu, and Xiaoqin Cui. "Prestack seismic inversion with structural constraints." Interpretation 9, no. 2 (May 1, 2021): T495—T506. http://dx.doi.org/10.1190/int-2020-0209.1.

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Prestack seismic inversion usually suffers from a lower signal-to-noise ratio, which could result in unstable inversion results. The conventional multitrace lateral constrained inversion blurs steeply dipping layers, whereas the simple structural constrained inversion is affected by noise. To solve this issue, an inversion method with multiple constraints is proposed, which include (1) a local smoothing operator is used to suppress the inversion anomalies caused by data noise, (2) a difference operator is used to protect the stratum boundary, and (3) a structural dipping constraint is used to enhance the characterization of the possible dipping stratum. The multiconstraint inversion (MCI) method suppresses the inversion anomalies caused by data noise without blurring the stratum boundary. The effects of different constraints in the inversion process and the influence of noise on the inversion results are analyzed. In MCI, the regularization coefficient of each constraint operator is dynamically changed, thereby controlling the significance of each regularization term in the inversion. The proposed algorithm is tested on synthetic and field data, which demonstrate its effectiveness and improved accuracy on the inversion results.

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Catapano, I., L. Crocco, and T. Isernia. "A feasibility study of a quantitative microwave tomography technique for structural monitoring." Near Surface Geophysics 8, no. 5 (May 1, 2010): 389–96. http://dx.doi.org/10.3997/1873-0604.2010014.

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Al-Hazaimay, Sadam, Johan A. Huisman, Egon Zimmermann, and Harry Vereecken. "Using electrical anisotropy for structural characterization of sediments: an experimental validation study." Near Surface Geophysics 14, no. 4 (March 1, 2016): 357–69. http://dx.doi.org/10.3997/1873-0604.2016026.

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Ali, Abdu Elazeem Osman Adam, Zhan Liu, Yongliang Bai, Abdalla Gumaa Farwa, Abboud Suliman Ahmed, and Guomin Peng. "A stable gravity downward continuation for structural delineation in Sulu Sea region." Journal of Applied Geophysics 155 (August 2018): 26–35. http://dx.doi.org/10.1016/j.jappgeo.2018.05.009.

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Cheng, Liang, Shangxu Wang, Wanwan Wei, Haoyang Gao, Zizhao Yu, Changjun Zhu, and Jinlei Xiu. "Structural geosteering constrained multi-trace sparse reflectivity inversion based on mixed norms." Journal of Applied Geophysics 172 (January 2020): 103880. http://dx.doi.org/10.1016/j.jappgeo.2019.103880.

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Shapovalov, Vladimir, Victor Yavna, Andrei Kochur, Zelimkhan Khakiev, Sergey Sulavko, Philippe Daniel, and Alexander Kruglikov. "Application of GPR for determining electrophysical properties of structural layers and materials." Journal of Applied Geophysics 172 (January 2020): 103913. http://dx.doi.org/10.1016/j.jappgeo.2019.103913.

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46

Czarnecka, K. "Interpretation of vertical tectonic movements supported by structural geophysical prospecting." Journal of Geodynamics 9, no. 2-4 (July 1988): 343–48. http://dx.doi.org/10.1016/s0264-3707(88)80087-5.

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Vallée, Marc A., William A. Morris, Stéphane Perrouty, Robert G. Lee, Ken Wasyliuk, Julia J. King, Kevin Ansdell, et al. "Geophysical inversion contributions to mineral exploration: lessons from the Footprints project." Canadian Journal of Earth Sciences 56, no. 5 (May 2019): 525–43. http://dx.doi.org/10.1139/cjes-2019-0009.

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Magnetic and gravity inversions are used to create 2D or 3D models of the magnetic susceptibility and density, respectively, using potential field data. Unconstrained inversions generate an output based on mathematical constraints imposed by the inversion algorithm. Constrained inversions integrate lithological, structural, and petrophysical information in the inversion process to produce more geologically meaningful results. This study analyses the validity of this assertion in the context of the NSERC-CMIC Mineral Exploration Footprints project. Unconstrained and constrained geophysical inversions were computed for three mining sites: a gold site (Canadian Malartic, Québec), a copper site (Highland Valley, British Columbia), and a uranium site (Millennium – McArthur River, Saskatchewan). After initially computing unconstrained inversions, constrained inversions were developed using physical property measurements, which directly link geophysics to geology, and lithological boundaries extracted from an interpreted geological model. While each derived geological model is consistent with the geophysical data, each site exhibited some magnetic complexity that confounded the inversion. The gold site includes regions with a strong magnetic signature that masks the more weakly magnetic zone, thereby hiding the magnetic signature associated with the ore body. Initial unconstrained inversions for the copper site yielded solutions with invalid depth extent. A consistency between the constrained model and the geological model is reached with iterative changes to the depth extent of the model. At the uranium site, the observed magnetic signal is weak, but the inversion provided some insights that could be interpreted in terms of an already known complexly folded geological model.

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Soeparyono, N., and P. Lennox. "Structural styles, Cepu oil fields, Java, Indonesia." Exploration Geophysics 22, no. 2 (June 1991): 369–74. http://dx.doi.org/10.1071/eg991369.

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Van Dam, R., L. A. Gutierrez, V. T. McLemore, G. W. Wilson, J. M. H. Hendrickx, and B. M. Walker. "Near Surface Geophysics for the Structural Analysis of a Mine Rock Pile, Northern New Mexico." Journal American Society of Mining and Reclamation 2005, no. 1 (2005): 1178–201. http://dx.doi.org/10.21000/jasmr05011178.

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Van Dam, Remke L., Luiza A. Gutierrez, Virginia T. McLemore, G. Ward Wilson, Jan M. H. Hendrickx, and Bruce M. Walker. "NEAR SURFACE GEOPHYSICS FOR THE STRUCTURAL ANALYSIS OF A MINE ROCK PILE, NORTHERN NEW MEXICO." Journal American Society of Mining and Reclamation 2005, no. 1 (June 30, 2005): 1178–201. http://dx.doi.org/10.21000/jasmr0501178.

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Journal articles on the topic 'Structural Geophysics Geophysics'

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