Articles | Volume 10, issue 2
https://doi.org/10.5194/gi-10-313-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gi-10-313-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
29 Nov 2021
Research article |
| 29 Nov 2021
| 29 Nov 2021
A towed magnetic gradiometer array for rapid, detailed imaging of utility, geological, and archaeological targets
Hydrogeophysics Group, Department of Geoscience, Aarhus University,
Aarhus, 8000, Denmark
Esben Auken
Hydrogeophysics Group, Department of Geoscience, Aarhus University,
Aarhus, 8000, Denmark
Geological Survey of Denmark and Greenland, Copenhagen, 1350, Denmark
Jakob Juul Larsen
Department of Electrical and Computer Engineering, Aarhus University,
Aarhus, 8000, Denmark
Anders Vest Christiansen
Hydrogeophysics Group, Department of Geoscience, Aarhus University,
Aarhus, 8000, Denmark
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Geosci. Instrum. Method. Data Syst., 11, 323–333, https://doi.org/10.5194/gi-11-323-2022, https://doi.org/10.5194/gi-11-323-2022, 2022
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Geosci. Instrum. Method. Data Syst., 11, 307–321, https://doi.org/10.5194/gi-11-307-2022, https://doi.org/10.5194/gi-11-307-2022, 2022
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Geosci. Instrum. Method. Data Syst., 11, 219–222, https://doi.org/10.5194/gi-11-219-2022, https://doi.org/10.5194/gi-11-219-2022, 2022
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The commercial off-the-shelf (COTS) PNI RM3100 magnetometer was tested for single-event latchup (SEL) at Lawrence Berkeley National Laboratory's heavy-ion beam and did not experience any single-event effects at a linear energy transfer >75 MeV cm2 mg−1. Coupled with previous total ionizing dose (TID) testing at the University of Michigan and NASA Goddard Space Flight Center that showed no degradation in performance up to 150 kRad(SI), the COTS PNI RM3100 is extremely radiation tolerant.
David M. Miles, Richard Dvorsky, Kenton Greene, Christian T. Hansen, B. Barry Narod, and Michael D. Webb
Geosci. Instrum. Method. Data Syst., 11, 111–126, https://doi.org/10.5194/gi-11-111-2022, https://doi.org/10.5194/gi-11-111-2022, 2022
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We present an experiment intended to enable extremely low-noise magnetic field measurements. We manufactured fluxgate magnetometer cores using two metal alloys, two geometries, two foil thicknesses, and six different heat treatments and compared the resulting material properties, power consumption, and magnetic noise. Our results suggest that thinner foils, potentially using a new copper alloy, manufactured into continuous racetrack washers may provide excellent performance in fluxgate sensors.
Ye Zhu, Aimin Du, Hao Luo, Donghai Qiao, Ying Zhang, Yasong Ge, Jiefeng Yang, Shuquan Sun, Lin Zhao, Jiaming Ou, Zhifang Guo, and Lin Tian
Geosci. Instrum. Method. Data Syst., 10, 227–243, https://doi.org/10.5194/gi-10-227-2021, https://doi.org/10.5194/gi-10-227-2021, 2021
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The Low Orbit Pearl Satellites measure magnetic field with high spatial coverage. Although there is no magnetic cleanliness to the satellites, the triple sensor configuration enables removal of interference. Results show they can capture the Earth’s internal as well as external fields from the magnetosphere–ionosphere current system. This study implies that a large number of small low-cost satellites without magnetic cleanliness could be the future for space magnetic exploration.
Yasuhito Narita, Ferdinand Plaschke, Werner Magnes, David Fischer, and Daniel Schmid
Geosci. Instrum. Method. Data Syst., 10, 13–24, https://doi.org/10.5194/gi-10-13-2021, https://doi.org/10.5194/gi-10-13-2021, 2021
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The systematic error of calibrated fluxgate magnetometer data is studied for a spinning spacecraft. The major error comes from the offset uncertainty when the ambient magnetic field is low, while the error represents the combination of non-orthogonality, misalignment to spacecraft reference direction, and gain when the ambient field is high. The results are useful in developing future high-precision magnetometers and an error estimate in scientific studies using magnetometer data.
Leonardo H. Regoli, Mark B. Moldwin, Connor Raines, Tom A. Nordheim, Cameron A. Miller, Martin Carts, and Sara A. Pozzi
Geosci. Instrum. Method. Data Syst., 9, 499–507, https://doi.org/10.5194/gi-9-499-2020, https://doi.org/10.5194/gi-9-499-2020, 2020
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Ovidiu Dragoş Constantinescu, Hans-Ulrich Auster, Magda Delva, Olaf Hillenmaier, Werner Magnes, and Ferdinand Plaschke
Geosci. Instrum. Method. Data Syst., 9, 451–469, https://doi.org/10.5194/gi-9-451-2020, https://doi.org/10.5194/gi-9-451-2020, 2020
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Andreas Pollinger, Christoph Amtmann, Alexander Betzler, Bingjun Cheng, Michaela Ellmeier, Christian Hagen, Irmgard Jernej, Roland Lammegger, Bin Zhou, and Werner Magnes
Geosci. Instrum. Method. Data Syst., 9, 275–291, https://doi.org/10.5194/gi-9-275-2020, https://doi.org/10.5194/gi-9-275-2020, 2020
Ferdinand Plaschke
Geosci. Instrum. Method. Data Syst., 8, 285–291, https://doi.org/10.5194/gi-8-285-2019, https://doi.org/10.5194/gi-8-285-2019, 2019
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Measuring the magnetic field onboard spacecraft requires regular in-flight calibration activities. Among those, determining the output of magnetometers under vanishing ambient magnetic fields, the so-called magnetometer offsets, is essential. Typically, characteristic rotations in solar wind magnetic fields are used to obtain these offsets. This paper addresses the question of how many solar wind data are needed to reach certain accuracy levels in offset determination.
David M. Miles, Miroslaw Ciurzynski, David Barona, B. Barry Narod, John R. Bennest, Andy Kale, Marc Lessard, David K. Milling, Joshua Larson, and Ian R. Mann
Geosci. Instrum. Method. Data Syst., 8, 227–240, https://doi.org/10.5194/gi-8-227-2019, https://doi.org/10.5194/gi-8-227-2019, 2019
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Fluxgate magnetometers provide magnetic field measurements for geophysics and space physics. A low-noise ferromagnetic ring core typically determines the noise performance of the instrument. Much of the basic research into producing low-noise fluxgate sensors was completed in the 1960s for military purposes and was never publicly released. We present a manufacturing approach that can consistently produce fluxgate ring cores with a noise performance comparable to the legacy ring cores used today.
Victor G. Getmanov, Alexei D. Gvishiani, and Roman V. Sidorov
Geosci. Instrum. Method. Data Syst., 8, 209–215, https://doi.org/10.5194/gi-8-209-2019, https://doi.org/10.5194/gi-8-209-2019, 2019
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The material in this research paper is intended for specialists engaged in digital processing of geomagnetic field measurements. A technique is discussed that can help to reduce the errors in measurements and can be applied in various tasks of digital processing of geomagnetic data from vector magnetometers and other three-component data. The results of the tests on model and real geomagnetic data are provided for the algorithm along with the conclusions about its possibilities.
Bertwin M. de Groot and Lennart V. de Groot
Geosci. Instrum. Method. Data Syst., 8, 217–225, https://doi.org/10.5194/gi-8-217-2019, https://doi.org/10.5194/gi-8-217-2019, 2019
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Our knowledge of the Earth's magnetic field arises from magnetic signals stored in lavas. In rugged volcanic terrain, however, the magnetization of the underlying flows may influence the magnetic field as recorded by newly formed flows on top. To measure these local magnetic anomalies, we developed a low-cost field magnetometer with superior accuracy and user-friendliness. The first measurements on Mt. Etna show local magnetic variations that are much larger than expected.
David M. Miles, Andrew D. Howarth, and Greg A. Enno
Geosci. Instrum. Method. Data Syst., 8, 187–195, https://doi.org/10.5194/gi-8-187-2019, https://doi.org/10.5194/gi-8-187-2019, 2019
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Measurements from the magnetic field instrument on the Cassiope spacecraft were found to be degraded by an artifact of how the instrument tracks the changing magnetic field as the spacecraft orbits the Earth. We present a process to characterize this effect on orbit and compensate for it in the post–processing of the data. This work allows the instrument to accurately track rapidly changing local fields without loss of measurement fidelity and improves the high–frequency noise of the data.
Trevor A. Bowen, Elena Zhivun, Arne Wickenbrock, Vincent Dumont, Stuart D. Bale, Christopher Pankow, Gregory Dobler, Jonathan S. Wurtele, and Dmitry Budker
Geosci. Instrum. Method. Data Syst., 8, 129–138, https://doi.org/10.5194/gi-8-129-2019, https://doi.org/10.5194/gi-8-129-2019, 2019
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We highlight the development of a low-cost portable sensor array to study magnetic fields in urban areas. Recent advancements in urban science have demonstrated significant utility in characterizing a city based on physical measurements. Magnetic fields of cities are characterized by significant noise; in the case of the San Francisco Bay Area, this noise is dominated by the BART train system. We demonstrate an ability to identify and extract BART noise from the urban magnetic environment.
Ferdinand Plaschke, Hans-Ulrich Auster, David Fischer, Karl-Heinz Fornaçon, Werner Magnes, Ingo Richter, Dragos Constantinescu, and Yasuhito Narita
Geosci. Instrum. Method. Data Syst., 8, 63–76, https://doi.org/10.5194/gi-8-63-2019, https://doi.org/10.5194/gi-8-63-2019, 2019
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Raw output of spacecraft magnetometers has to be converted into meaningful units and coordinate systems before it is usable for scientific applications. This conversion is defined by 12 calibration parameters, 8 of which are more easily determined in flight if the spacecraft is spinning. We present theory and advanced algorithms to determine these eight parameters. They take into account the physical magnetometer and spacecraft behavior, making them superior to previously published algorithms.
David M. Miles, B. Barry Narod, David K. Milling, Ian R. Mann, David Barona, and George B. Hospodarsky
Geosci. Instrum. Method. Data Syst., 7, 265–276, https://doi.org/10.5194/gi-7-265-2018, https://doi.org/10.5194/gi-7-265-2018, 2018
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We present a proof-of-concept space-flight instrument that can simultaneously make measurements of both the low- and high-frequency local magnetic field. Previously, this would have required two separate instruments that would normally have had to be mounted separately on long deployable booms to keep them from interfering. This new hybrid instrument is expected to be particularly useful on extremely small spacecraft, such as CubeSats, which can only accommodate a few instruments.
Leonardo H. Regoli, Mark B. Moldwin, Matthew Pellioni, Bret Bronner, Kelsey Hite, Arie Sheinker, and Brandon M. Ponder
Geosci. Instrum. Method. Data Syst., 7, 129–142, https://doi.org/10.5194/gi-7-129-2018, https://doi.org/10.5194/gi-7-129-2018, 2018
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The presence of magnetic fields in space dominate the way planets interact with different types of plasmas. Thus, measuring them is extremely important when studying space. We present an instrument capable of measuring magnetic fields at a fraction of the cost, power and size of traditional magnetometers. With this technology, a science-grade magnetometer for small satellites can be achieved, enabling the study of the space environment with large clusters of sensors in future missions.
Heinz-Peter Brunke and Jürgen Matzka
Geosci. Instrum. Method. Data Syst., 7, 1–9, https://doi.org/10.5194/gi-7-1-2018, https://doi.org/10.5194/gi-7-1-2018, 2018
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The long-term drift of magnetometers at geomagnetic observatories is calibrated by a non-magnetic theodolite. We propose a numerical method to evaluate such absolute measurements in a new, more general manner. It is more flexible and helps to identify and correct or discard erroneous measurements. We derive this method and give examples showing how it improves the quality and reliability of the calibrations parameters (the so-called baseline values) of an observatory magnetometer.
Heinz-Peter Brunke, Rudolf Widmer-Schnidrig, and Monika Korte
Geosci. Instrum. Method. Data Syst., 6, 487–493, https://doi.org/10.5194/gi-6-487-2017, https://doi.org/10.5194/gi-6-487-2017, 2017
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In magnetic observatory data, according to the INTERMAGNET definitive 1 s data standard, the fluxgate magnetometer self noise usually covers the natural signal for frequencies higher than about 30 mHz. We present a numerical method how to merge the data with induction coil data in order to drastically reduce noise and to fill the entire possible bandwidth with information on the earth magnetic field. In spectrograms we visualize interesting phenomena revealed with the method.
Roman Sidorov, Anatoly Soloviev, Roman Krasnoperov, Dmitry Kudin, Andrei Grudnev, Yury Kopytenko, Andrei Kotikov, and Pavel Sergushin
Geosci. Instrum. Method. Data Syst., 6, 473–485, https://doi.org/10.5194/gi-6-473-2017, https://doi.org/10.5194/gi-6-473-2017, 2017
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Saint Petersburg Observatory was founded as a geomagnetic branch of the Voyeikovo magnetic and meteorological observatory in the late 1960s. In 2012 the station was upgraded to INTERMAGNET standard and in 2016 it was officially certified as SPG INTERMAGNET magnetic observatory. The SPG data can be downloaded via http://intermagnet.org or
http://geomag.gcras.ru . This paper describes the way the SPG observatory made to become an international geomagnetic network member.
David M. Miles, Ian R. Mann, Andy Kale, David K. Milling, Barry B. Narod, John R. Bennest, David Barona, and Martyn J. Unsworth
Geosci. Instrum. Method. Data Syst., 6, 377–396, https://doi.org/10.5194/gi-6-377-2017, https://doi.org/10.5194/gi-6-377-2017, 2017
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Fluxgate magnetometers are an important geophysical tool but are typically sensitive to changes in sensor temperature. We used a novel, low-cost calibration procedure to compare six matched sensors in which the material used as the mechanical support is varied and found that 30 % glass-filled PEEK engineering plastic is a good candidate for sensors. It is more economical, easier to machine, lighter, and more robust than historically used machinable ceramic.
Wahyudi, Nurul Khakhim, Tri Kuntoro, Djati Mardiatno, Afif Rakhman, Anas Setyo Handaru, Adien Akhmad Mufaqih, and Theodosius Marwan Irnaka
Geosci. Instrum. Method. Data Syst., 6, 319–327, https://doi.org/10.5194/gi-6-319-2017, https://doi.org/10.5194/gi-6-319-2017, 2017
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In geophysics exploration, measuring earth's magnetic field using magnetometers is a necessity to resolve earth's subsurface structure. In this paper we offer an open-schematic fluxgate magnetometer (Magnetogama) that will help people build their own magnetometer. We focus on how to assemble and record earth's magnetic response. Several sensitivity tests were performed to make sure that Magnetogama has the capability to be used in exploration.
Andriy Marusenkov
Geosci. Instrum. Method. Data Syst., 6, 301–309, https://doi.org/10.5194/gi-6-301-2017, https://doi.org/10.5194/gi-6-301-2017, 2017
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The paper discusses the possibility of improving the quality of geomagnetic variation monitoring at ground observatories. The new fluxgate sensor and electronics with upgraded temperature and noise characteristics are described. It is supposed that the application of the results and recommendations discussed in the paper will allow a fluxgate magnetometer to be created with an outstanding level of parameters.
László Hegymegi, János Szöllősy, Csaba Hegymegi, and Ádám Domján
Geosci. Instrum. Method. Data Syst., 6, 279–284, https://doi.org/10.5194/gi-6-279-2017, https://doi.org/10.5194/gi-6-279-2017, 2017
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The authors developed and built a digital non-magnetic declination–inclination magnetometer which gives all measurement data in digital form. Use of this instrument significantly decreases the possibility of observation errors and minimises handwork. We showed that this device is suitable for absolute magnetic control measurements, and it is more convenient, user friendly and effective than the traditional ones.
Santiago Marsal, Juan José Curto, Joan Miquel Torta, Alexandre Gonsette, Vicent Favà, Jean Rasson, Miquel Ibañez, and Òscar Cid
Geosci. Instrum. Method. Data Syst., 6, 269–277, https://doi.org/10.5194/gi-6-269-2017, https://doi.org/10.5194/gi-6-269-2017, 2017
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Commercial solutions for an automated DI-flux are practically reduced to the AutoDIF and the GyroDIF. We analyze the pros and cons of both in terms of suitability at the Livingston Island geomagnetic observatory, Antarctica. We conclude that the GyroDIF is more suitable for harsh conditions due to its simpler infrastructure. We also show the instrument housing design and its control electronics. Our experiences can benefit the geomagnetic community, which often faces similar challenges.
Jean L. Rasson, Olivier Hendrickx, and Jean-Luc Marin
Geosci. Instrum. Method. Data Syst., 6, 257–261, https://doi.org/10.5194/gi-6-257-2017, https://doi.org/10.5194/gi-6-257-2017, 2017
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In geomagnetism, geodesy and in general disciplines requiring orientation on Earth, accurately finding the direction of true north is a challenge. This paper describes a method to do so using a traditional theodolite and the proposed apparatus: an electro-optical add-on. The details of the concepts, design and operation of the add-on are explained.
David Fischer, Werner Magnes, Christian Hagen, Ivan Dors, Mark W. Chutter, Jerry Needell, Roy B. Torbert, Olivier Le Contel, Robert J. Strangeway, Gernot Kubin, Aris Valavanoglou, Ferdinand Plaschke, Rumi Nakamura, Laurent Mirioni, Christopher T. Russell, Hannes K. Leinweber, Kenneth R. Bromund, Guan Le, Lawrence Kepko, Brian J. Anderson, James A. Slavin, and Wolfgang Baumjohann
Geosci. Instrum. Method. Data Syst., 5, 521–530, https://doi.org/10.5194/gi-5-521-2016, https://doi.org/10.5194/gi-5-521-2016, 2016
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This paper describes frequency and timing calibration, modeling and data processing and calibration for MMS magnetometers, resulting in a merged search choil and fluxgate data product.
Panagiotis P. Zacharias, Elpida G. Chatzineofytou, Sotirios T. Spantideas, and Christos N. Capsalis
Geosci. Instrum. Method. Data Syst., 5, 281–288, https://doi.org/10.5194/gi-5-281-2016, https://doi.org/10.5194/gi-5-281-2016, 2016
Marina Díaz-Michelena, Rolf Kilian, Ruy Sanz, Francisco Rios, and Oscar Baeza
Geosci. Instrum. Method. Data Syst., 5, 127–142, https://doi.org/10.5194/gi-5-127-2016, https://doi.org/10.5194/gi-5-127-2016, 2016
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The present manuscript is written as the result of an exhaustive field work with MOURA instrument on relevant sites on Earth. MOURA magnetometer was developed for Mars MetNet precursor mission to Mars. In this work we have demonstrated the capabilities of the instrument in terrestrial analogues of Mars, which cover a huge variability range in the magnetic anomalies intensities. Apart from its suitability for prospections, we insist on its advanced performance regarding paleomagnetic information.
M. Díaz-Michelena, R. Sanz, M. F. Cerdán, and A. B. Fernández
Geosci. Instrum. Method. Data Syst., 4, 1–18, https://doi.org/10.5194/gi-4-1-2015, https://doi.org/10.5194/gi-4-1-2015, 2015
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In situ magnetometry is key for planetary mineralogy. However, since magnetic instrumentation is considered secondary in Mars and Moon landers and rovers, magnetometers have often very restricted envelopes of mass, volume and power, and consequently limited functionality.
In this work, it is presented the capability of MOURA small magnetometer and gradiometer to open a wide and novel scientific research on Mars mineralogy and paleomagnetism through the very complex calibration process.
B. B. Narod
Geosci. Instrum. Method. Data Syst., 3, 201–210, https://doi.org/10.5194/gi-3-201-2014, https://doi.org/10.5194/gi-3-201-2014, 2014
R. Čop, G. Milev, D. Deželjin, and J. Kosmač
Geosci. Instrum. Method. Data Syst., 3, 135–141, https://doi.org/10.5194/gi-3-135-2014, https://doi.org/10.5194/gi-3-135-2014, 2014
L. N. S. Alconcel, P. Fox, P. Brown, T. M. Oddy, E. L. Lucek, and C. M. Carr
Geosci. Instrum. Method. Data Syst., 3, 95–109, https://doi.org/10.5194/gi-3-95-2014, https://doi.org/10.5194/gi-3-95-2014, 2014
R. Nakamura, F. Plaschke, R. Teubenbacher, L. Giner, W. Baumjohann, W. Magnes, M. Steller, R. B. Torbert, H. Vaith, M. Chutter, K.-H. Fornaçon, K.-H. Glassmeier, and C. Carr
Geosci. Instrum. Method. Data Syst., 3, 1–11, https://doi.org/10.5194/gi-3-1-2014, https://doi.org/10.5194/gi-3-1-2014, 2014
M. van de Kamp
Geosci. Instrum. Method. Data Syst., 2, 289–304, https://doi.org/10.5194/gi-2-289-2013, https://doi.org/10.5194/gi-2-289-2013, 2013
D. M. Miles, J. R. Bennest, I. R. Mann, and D. K. Millling
Geosci. Instrum. Method. Data Syst., 2, 213–224, https://doi.org/10.5194/gi-2-213-2013, https://doi.org/10.5194/gi-2-213-2013, 2013
A. Khokhlov, J. L. Le Mouël, and M. Mandea
Geosci. Instrum. Method. Data Syst., 2, 1–9, https://doi.org/10.5194/gi-2-1-2013, https://doi.org/10.5194/gi-2-1-2013, 2013
M. A. Pudney, C. M. Carr, S. J. Schwartz, and S. I. Howarth
Geosci. Instrum. Method. Data Syst., 1, 103–109, https://doi.org/10.5194/gi-1-103-2012, https://doi.org/10.5194/gi-1-103-2012, 2012
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Short summary
We have developed a towed magnetic gradiometer system for rapid acquisition of magnetic and magnetic gradient maps. This high-resolution system is flexible and has applications to utility detection, archaeology, unexploded ordnance, or any other applications where high-resolution maps of the magnetic field or gradient are required. Processing of the data has been simplified as much as possible to facilitate rapid results and interpretations.
We have developed a towed magnetic gradiometer system for rapid acquisition of magnetic and...
