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Journal articles on the topic 'Earth resistance (Geophysics) Measurement'

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Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

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1

Scambos, T. A., R. Ross, T. Haran, R. Bauer, D. G. Ainley, K. W. Seo, M. De Keyser, A. Behar, and D. R. MacAyeal. "A camera and multisensor automated station design for polar physical and biological systems monitoring: AMIGOS." Journal of Glaciology 59, no. 214 (2013): 303–14. http://dx.doi.org/10.3189/2013jog12j170.

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AbstractThe Automated Meteorology–Ice/Indigenous species–Geophysics Observation System (AMIGOS) consists of a set of measurement instruments and camera(s) controlled by a single-board computer with a simplified Linux operating system and an Iridium satellite modem supporting two-way communication. Primary features of the system relevant to polar operations are low power requirements, daily data uploading, reprogramming, tolerance for low temperatures, and various approaches for automatic resets and recovery from low power or cold shutdown. Instruments include a compact weather station, single- or dual-frequency GPS, solar flux and reflectivity sensors, sonic snow gauges, simplified radio-echo sounder, and resistance thermometer string in the firn column. In the current state of development, there are two basic designs. One is intended for in situ observations of glacier conditions. The other supports a high-resolution camera for monitoring biological or geophysical systems from short distances (100 m to 20 km). The stations have been successfully used in several locations for operational support, monitoring rapid ice changes in response to climate change or iceberg drift, and monitoring penguin colony activity. As of August 2012, there are nine AMIGOS systems installed, all on the Antarctic continent or in the surrounding ocean.

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Hill, Graham J. "On the Use of Electromagnetics for Earth Imaging of the Polar Regions." Surveys in Geophysics 41, no. 1 (September 12, 2019): 5–45. http://dx.doi.org/10.1007/s10712-019-09570-8.

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Abstract The polar regions are host to fundamental unresolved challenges in Earth studies. The nature of these regions necessitates the use of geophysics to address these issues, with electromagnetic and, in particular, magnetotelluric studies finding favour and being applied over a number of different scales. The unique geography and climatic conditions of the polar regions means collecting magnetotelluric data at high latitudes, which presents challenges not typically encountered and may result in significant measurement errors. (1) The very high contact resistance between electrodes and the surficial snow and ice cover (commonly MΩ) can interfere with the electric field measurement. This is overcome by using custom-designed amplifiers placed at the active electrodes to buffer their high impedance contacts. (2) The proximity to the geomagnetic poles requires verification of the fundamental assumption in magnetotellurics that the magnetic source field is a vertically propagating, horizontally polarised plane wave. Behaviour of the polar electro-jet must be assessed to identify increased activity (high energy periods) that create strong current systems and may generate non-planar contributions. (3) The generation of ‘blizstatic’, localised random electric fields caused by the spin drift of moving charged snow and ice particles that produce significant noise in the electric fields during periods of strong winds. At wind speeds above ~ 10 m s−1, the effect of the distortion created by the moving snow is broad-band. Station occupation times need to be of sufficient length to ensure data are collected when wind speed is low. (4) Working on glaciated terrain introduces additional safety challenges, e.g., weather, crevasse hazards, etc. Inclusion of a mountaineer in the team, both during the site location planning and onsite operations, allows these hazards to be properly managed. Examples spanning studies covering development and application of novel electromagnetic approaches for the polar regions as well as results from studies addressing a variety of differing geologic questions are presented. Electromagnetic studies focusing on near-surface hydrologic systems, glacial and ice sheet dynamics, as well as large-scale volcanic and tectonic problems are discussed providing an overview of the use of electromagnetic methods to investigate fundamental questions in solid earth studies that have both been completed and are currently ongoing in polar regions.

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Zemanian, A. H., and B. Anderson. "Modeling of borehole resistivity measurements using infinite electrical grids." GEOPHYSICS 52, no. 11 (November 1987): 1525–34. http://dx.doi.org/10.1190/1.1442269.

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An infinite electrical resistive grid generated by a finite‐difference approximation to Poisson’s equation in cylindrical coordinates with no azimuthal variation has been used to model borehole resistivity measurements. The medium surrounding the borehole is infinite in extent and its resistivity varies only in the radial direction. As a result, the branch resistance values of the infinite grid also vary only in the radial direction. A continued fraction of Laurent operators determines the node voltages along the borehole’s surface. Use of an operational calculus based upon the finite Fourier transformation converts the continued fraction into a readily computed form. This yields new formulas for apparent resistivity, given various resistivity measuring arrays and a resistivity profile in the radial direction. In contrast to classical methods, the need to match boundary conditions at the interface of a cylindrically layered earth is eliminated, so that the procedure is just as easily applied to a continuous resistivity profile as it is to a stepped profile. Moreover, the method is computationally fast by virtue of the fast Fourier transform algorithm and the avoidance of boundary‐condition matching. The speed and versatility of this model make it useful for studying the effects of complex invasion on the response of resistivity tools.

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Gai‐shan, Zhao. "Asymptotic formula of the transform function for the layered‐earth potential and its applications to interpretation of resistivity sounding data." GEOPHYSICS 50, no. 9 (September 1985): 1513–14. http://dx.doi.org/10.1190/1.1442021.

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With the development of computation techniques based on the digital linear filter method and the wide use of computers, automatic interpretation of vertical electric sounding (VES) data has become practical and common. The digital linear filter method developed in Ghosh (1971a, b) makes solving the inverse problem of VES easier and more practical, because it requires less computer time and storage space, is more accurate than other methods, and does not restrict the number of layers, electrode spacings, and layer depths. However, considerable ambiguity in the interpretation may result when many layers are involved. This means that strongly differing layer distributions may yield apparent resistivity sounding curves that, although not equal, differ so slightly that they cannot be accurately distinguished. In other words, the interpretation provided is only one of many acceptable interpretations, all of which are consistent with the field curves within the accuracy of measurements. Some combination parameters obtained may be useful in this case, and they are needed sometimes. I present a new method to interpret resistivity sounding data, by which some combination parameters such as total longitudinal conductance, total transverse resistance, and the resistivity of the substratum can be obtained.

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Peck, Lindamae, Richard C. Nolen-Hoeksema, Christopher C. Barton, and Robert B. Gordon. "Measurement of the resistance of imperfectly elastic rock to the propagation of tensile cracks." Journal of Geophysical Research 90, B9 (1985): 7827. http://dx.doi.org/10.1029/jb090ib09p07827.

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6

Prémaillon, Mélody, Vincent Regard, Thomas J. B. Dewez, and Yves Auda. "GlobR2C2 (Global Recession Rates of Coastal Cliffs): a global relational database to investigate coastal rocky cliff erosion rate variations." Earth Surface Dynamics 6, no. 3 (August 9, 2018): 651–68. http://dx.doi.org/10.5194/esurf-6-651-2018.

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Abstract. Rocky coast erosion (i.e., cliff retreat) is caused by a complex interaction of various forcings that can be marine, subaerial or due to rock mass properties. From Sunamura's seminal work in 1992, it is known that cliff retreat rates are highly variable over at least four orders of magnitude, from 1 to 10 mm yr−1. While numerous local studies exist and explain erosion processes at specific sites, there is a lack of knowledge at the global scale. In order to quantify and rank the various parameters influencing erosion rates, we compiled existing local studies into a global database called GlobR2C2 (which stands for Global Recession Rates of Coastal Cliffs). This database reports erosion rates from publications, cliff setting and measurement specifications; it is compiled from peer-reviewed articles and national databases. In order to be homogeneous, marine and climatic forcings were recorded from global models and reanalyses. Currently, GlobR2C2 contains 58 publications that represent 1530 studied cliffs and more than 1680 estimated erosion rate. A statistical analysis was conducted on this database to explore the links between erosion rates and forcings at a global scale. Rock resistance, inferred using the criterion of Hoek and Brown (1997), is the strongest signal explaining variation in erosion rate. Median erosion rates are 2.9 cm yr−1 for hard rocks, 10 cm yr−1 for medium rocks and 23 cm yr−1 for weak rocks. Concerning climate, only the number of frost days (number of day per year below 0 ∘C) for weak rocks shows a significant, positive, trend with erosion rate. The other climatic and marine forcings do not show any clear or significant relationship with cliff retreat rate. In this first version, GlobR2C2, with its current encompassing vision, has broad implications. Critical knowledge gaps have come to light and prompt a new coastal rocky shore research agenda. Further study of these questions is paramount if we one day hope to answer questions such as what the coastal rocky shore response to sea-level rise or increased storminess may be.

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Zhang, H., G. D. Egbert, A. D. Chave, Q. Huang, A. Kelbert, and S. Y. Erofeeva. "Constraints on the resistivity of the oceanic lithosphere and asthenosphere from seafloor ocean tidal electromagnetic measurements." Geophysical Journal International 219, no. 1 (July 11, 2019): 464–78. http://dx.doi.org/10.1093/gji/ggz315.

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SUMMARY The electromagnetic (EM) field generated by ocean tidal flow is readily detectable in both satellite magnetic field data, and in ocean-bottom measurements of electric and magnetic fields. The availability of accurate charts of tidal currents, constrained by assimilation of modern satellite altimetry data, opens the possibility of using tidal EM fields as a source to image mantle electrical resistivity beneath the ocean basins, as highlighted by the recent success in defining the globally averaged lithosphere–asthenosphere boundary (LAB) with satellite data. In fact, seafloor EM data would be expected to provide better constraints on the structure of resistive oceanic lithosphere, since the toroidal magnetic mode, which can constrain resistive features, is a significant component of the tidal EM field within the ocean, but is absent above the surface (in particular in satellite data). Here we consider this issue in more detail, using a combination of simplified theoretical analysis and 1-D and 3-D numerical modelling to provide a thorough discussion of the sensitivity of satellite and seafloor data to subsurface electrical structure. As part of this effort, and as a step toward 3-D inversion of seafloor tidal data, we have developed a new flexible 3-D spherical-coordinate finite difference scheme for both global and regional scale modelling, with higher resolution models nested in larger scale solutions. We use the new 3-D model, together with Monte Carlo simulations of errors in tidal current estimates, to provide a quantitative assessment of errors in the computed tidal EM signal caused by uncertainty in the tidal source. Over the open ocean this component of error is below 0.01 nT in Bz at satellite height and 0.05 nT in Bx on the seafloor, well below typical signal levels. However, as coastlines are approached error levels can increase substantially. Both analytical and 3-D modelling demonstrate that the seafloor magnetic field is most sensitive to the lithospheric resistance (the product of resistivity and thickness), and is more weakly influenced (primarily in the phase) by resistivity of the underlying asthenosphere. Satellite data, which contain only the poloidal magnetic mode, are more sensitive to the conductive asthenosphere, but have little sensitivity to lithospheric resistance. For both seafloor and satellite data’s changes due to plausible variations in Earth parameters are well above error levels associated with source uncertainty, at least in the ocean interior. Although the 3-D modelling results are qualitatively consistent with theoretical analysis, the presence of coastlines and bathymetric variations generates a complex response, confirming that quantitative interpretation of ocean tidal EM fields will require a 3-D treatment. As an illustration of the nested 3-D scheme, seafloor data at five magnetic and seven electric stations in the northeastern Pacific (41○N, 165○W) are fit with trial-and-error forward modelling of a local domain. The simulation results indicate that the lithospheric resistance is roughly 7 × 108 Ωm2. The phase of the seafloor data in this region are inconsistent with a sharp transition between the resistive lithosphere and conductive asthenosphere.

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Kuzmenko, Eduard, and Sergiy Bagriy. "GEODYNAMICS." GEODYNAMICS 1(32)2022, no. 1(32) (June 28, 2022): 119–35. http://dx.doi.org/10.23939/jgd2022.02.119.

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The aim of the research is to substantiate the scientific foundations of an integrated approach to solving environmental and geological problems related to groundwater salinization in the Kalush mining region; quantitative evaluation of the dynamics of such salinization and its relationship with the river system based on geochemical and geophysical observations. The relevance of the research is determined by the need to solve the following tasks: 1) identification of the sources of the groundwater contamination; 2) determination of saline areas, including settlements within which drinking water horizons become unsuitable for the direct use; 3) characteristics of the dynamics, that is, the degree of salinity and the rate of its changes in space and time; 4) determination of the danger to the operation of water intake facilities; 5) determination of the risk of contamination of the river basin. The methodology consists in establishing the correlation between hydrogeochemical and electrometric observations, as well as determining the transition patterns from measurements of electrical resistance to the groundwater salinity. It also includes creating spatio-temporal models of groundwater salinity dynamics and assessing the risks of surface watercourses contamination taking into account its main sources and providing initial data for making management decisions. With the help of the hydrogeochemical observations (the groundwater mineralization) and electrical exploration (measurement of electrical resistance), correlations were established between the geophysical characteristics inherent in the aquifer and the groundwater mineralization. As a result, this made it possible to concretize the sources and determine the area and degree of salinization according to the planar geophysical surveys. Regime observations allowed us to establish the movement direction and speed of the salinity front. The obtained quantitative characteristics of the salinization dynamics of the aquifer allowed calculating the contamination risks of the Limnytsia and Dnister Rivers. The scientific novelty consists in the further development of the methods for assessing underground mineralization based on the results of geophysical research, including the method of electrical exploration. For the first time, spatio-temporal models of the groundwater mineralization dynamics in the territory of the Kalush mining region (KMR) were created. In addition, the assessment of the risks of the surface watercourse contamination (the Limnytsia and Dnister Rivers) was given, taking into account the main sources of contamination within the KMR. The application of the obtained results makes it possible to quickly research the areas associated with probable contamination of the territory, to provide initial data for further planning and management actions. A reliable forecast allows envisaging the measures for reducing the environmental load on the aquifer, which is the only drinking horizon for the town of Kalush.

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de Leeuw, Jan, Michael P. Lamb, Gary Parker, Andrew J. Moodie, Daniel Haught, Jeremy G. Venditti, and Jeffrey A. Nittrouer. "Entrainment and suspension of sand and gravel." Earth Surface Dynamics 8, no. 2 (June 3, 2020): 485–504. http://dx.doi.org/10.5194/esurf-8-485-2020.

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Abstract. The entrainment and suspension of sand and gravel are important for the evolution of rivers, deltas, coastal areas, and submarine fans. The prediction of a vertical profile of suspended sediment concentration typically consists of assessing (1) the concentration near the bed using an entrainment relation and (2) the upward vertical distribution of sediment in the water column. Considerable uncertainty exists in regard to both of these steps, especially the near-bed concentration. Most entrainment relations have been tested against limited grain-size-specific data, and no relations have been evaluated for gravel suspension, which can be important in bedrock and mountain rivers. To address these issues, we compiled a database with suspended sediment data from natural rivers and flume experiments, taking advantage of the increasing availability of high-resolution grain size measurements. We evaluated 12 dimensionless parameters that may determine entrainment and suspension relations and applied multivariate regression analysis. A best-fit two-parameter equation (r2=0.79) shows that near-bed entrainment, evaluated at 10 % of the flow depth, decreases with the ratio of settling velocity to skin-friction shear velocity (wsi/u∗skin), as in previous relations, and increases with Froude number (Fr), possibly due to its role in determining bedload-layer concentrations. We used the Rouse equation to predict concentration upward from the reference level and evaluated the coefficient βi, which accounts for differences in the turbulent diffusivity of sediment from the parabolic eddy viscosity model used in the Rouse derivation. The best-fit relation for βi (r2=0.40) indicates greater relative sediment diffusivities for rivers with greater flow resistance, possibly due to bedform-induced turbulence, and larger wsi/u∗skin; the latter dependence is nonlinear and therefore different from standard Rouse theory. In addition, we used empirical relations for gravel saltation to show that our relation for near-bed concentration also provides good predictions for coarse-grained sediment. The new relations extend the calibrated parameter space over a wider range in sediment sizes and flow conditions compared to previous work and result in 95 % of concentration data throughout the water column predicted within a factor of 9.

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10

Gailler, Lydie, Phillipe Labazuy, Edouard Régis, Aline Peltier, and Valérie Ferrazzini. "Active structures and thermal state of the Piton de la Fournaise summit revealed by combined UAV magnetic and thermal infrared measurements." Volcanica 5, no. 1 (February 3, 2022): 41–54. http://dx.doi.org/10.30909/vol.05.01.4154.

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In this study, we demonstrate the strong potential of combining Unmanned Aerial Vehicle (UAV)-based thermal infrared (IR) and magnetic measurements to image the thermal state of volcanic edifices, as well as the distribution of active volcano-tectonic features at depth. Since magnetization is strongly dependent on temperature and alteration, thermally active structures are also associated with a decrease in magnetization. Based on the analysis of recent combined magnetic and infrared acquisitions, we focus on the recent evolution of the summit activity at Piton de la Fournaise. The comparison clearly highlights zones of major thermal activity, alteration and high permeability, and potentially areas of low mechanical resistance. Those observations provide information on preferential pathways for future activity, and also provide constraints on fluid transfer, diffusion, and cooling processes occurring within the volcano subsurface. Through reiterations, such combined UAV measurements are therefore particularly relevant in monitoring volcanic hazards before, during and after eruptions.

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Gailler, Lydie, Phillipe Labazuy, Edouard Régis, Aline Peltier, and Valérie Ferrazzini. "Active structures and thermal state of the Piton de la Fournaise summit revealed by combined UAV magnetic and thermal infrared measurements." Volcanica 5, no. 1 (February 3, 2022): 61–74. http://dx.doi.org/10.30909/vol.05.01.6174.

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In this study, we demonstrate the strong potential of combining Unmanned Aerial Vehicle (UAV)-based thermal infrared (IR) and magnetic measurements to image the thermal state of volcanic edifices, as well as the distribution of active volcano-tectonic features at depth. Since magnetization is strongly dependent on temperature and alteration, thermally active structures are also associated with a decrease in magnetization. Based on the analysis of recent combined magnetic and infrared acquisitions, we focus on the recent evolution of the summit activity at Piton de la Fournaise. The comparison clearly highlights zones of major thermal activity, alteration and high permeability, and potentially areas of low mechanical resistance. Those observations provide information on preferential pathways for future activity, and also provide constraints on fluid transfer, diffusion, and cooling processes occurring within the volcano subsurface. Through reiterations, such combined UAV measurements are therefore particularly relevant in monitoring volcanic hazards before, during and after eruptions.

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Manik, Charla Tri Selda. "Measurement of Earth Value Using Earth Tester Measurement at Efarina University." Journal of Science Technology (JoSTec) 2, no. 1 (December 28, 2020): 42–47. http://dx.doi.org/10.55299/jostec.v2i1.51.

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Grounding refers to the connection of an electrical equipment or installation to the ground so that it can protect humans from electric shock , and secure installation components from the danger of abnormal current voltages . This grounding system has low resistance properties, so that the overcurrent in the installation network can be flowed quickly to the ground to minimize damage to equipment in the building and protect the people inside. This study reviews the measurement of grounding around the earth at the efarina university. To find out the condition of the grounding resistance at each grounding, it is necessary to measure each grounding by measuring directly on the grounding installation network using an earth tester using an electrode pin. The calculation of grounding resistance is based on the type of soil, the depth of the electrode rod. The results show that the earth around the campus lobby has met the General Electrical Installation Requirements (PUIL) standard, which is smaller than 5 ohms. However, for earthing around the health faculty, it does not meet the PUIL standard, which is less than 5 ohms.

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YAGIURA, Yoshiyuki, Hisashi CHIBA, Manabu TAKEMASA, Hideo NOMURA, Yukihiro AKASAKA, and Shinichi KUGA. "Groundwater Level Measurement through the Earth Resistance Variation." Japanese Geotechnical Journal 13, no. 4 (December 31, 2018): 423–30. http://dx.doi.org/10.3208/jgs.13.423.

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Liu, S., D. Mao, and L. Lu. "Measurement and estimation of the aerodynamic resistance." Hydrology and Earth System Sciences Discussions 3, no. 3 (May 12, 2006): 681–705. http://dx.doi.org/10.5194/hessd-3-681-2006.

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Abstract. Using two methods of eddy correlation system and evaporation pan to measure respectively the aerodynamic resistance over bare soil surface and maize field, this paper analyses the diurnal variation of the aerodynamic resistance and its relationship with wind speed. Based on direct measurements by eddy correlation system, an evaluation of the aerodynamic resistance models is made. These models include Thom model, Verma-Ronsenberg model, Monteith-Hatfield model, XieXianqun model, Mahrt-Ek model, Choudhury-1 model and Choudhury-2 model. The results show that: the distribution of the aerodynamic resistance takes a "U" type in the daytime and inverse "V" type at night. The aerodynamic resistance is a power function of wind speed. The aerodynamic resistances measured by eddy correlation system are in agreement with those measured by evaporation pan, but big differences occur when the evaporation rate is very small at night or rainy day. Choudhury-1 model, XieXianqun model and Thom model give the better agreement with the measurements by eddy correlation system both over bare soil surface and the maize field, while Mahrt-Ek Model and Monteith-Hatfield model perform worse.

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Li, Yan, Xiao Hua Sun, and Fu Shun Wang. "Design of High Precision Earth-Temperature Detection System." Applied Mechanics and Materials 427-429 (September 2013): 640–43. http://dx.doi.org/10.4028/www.scientific.net/amm.427-429.640.

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Based on platinum resistance as temperature medium, according to the measurement precision requirements during geothermal testing process, optimize the circuit design and segmented curve fitting were used, discussed the feasibility of realize high precision temperature detection. Combined with high precision temperature measurement circuit, through the single chip microcomputer control, segmented curve fitting the temperature sampling value, get the corresponding D-t curve, and compensate the nonlinear relationship of platinum resistance in the practical work, to achieve the purpose of accurate measurement of the temperature.

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Nor, N. Mohamad, R. Rajab, and K. Ramar. "Validation of the Calculation and Measurement Techniques of Earth Resistance Values." American Journal of Applied Sciences 5, no. 10 (October 1, 2008): 1313–17. http://dx.doi.org/10.3844/ajassp.2008.1313.1317.

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17

Kim, Jung-Ho, Robert Supper, David Ottowitz, Birgit Jochum, and Myeong-Jong Yi. "A new measurement protocol of direct current resistivity data." GEOPHYSICS 81, no. 2 (March 1, 2016): A7—A11. http://dx.doi.org/10.1190/geo2015-0419.1.

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We have developed a new protocol for measuring direct current (DC) resistivity data, in which self-potential (SP) data were measured immediately prior to obtaining the resistivity data. Based on this SP measurement, we have defined two different resistances: the forward resistance (i.e., a normalized potential difference caused by forward current injection) and the backward resistance (i.e., a normalized potential difference caused by backward current injection). This has allowed us to quantify distortions in the DC resistivity potential field caused by all unknown mechanisms, including ambient noises. In accordance with the proposed measurement protocol, we further devised a data-weighting method in a resistivity inversion for calculating more reasonable subsurface structures, and the method was based on the forward and backward resistances. Through inversion experiments using field resistivity data acquired by the proposed protocol, we have determined the validity and effectiveness of the proposed method.

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LaBrecque, Douglas, and William Daily. "Assessment of measurement errors for galvanic-resistivity electrodes of different composition." GEOPHYSICS 73, no. 2 (March 2008): F55—F64. http://dx.doi.org/10.1190/1.2823457.

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This research provides an empirical study of electrodes used to measure galvanic resistivity. The central element of this work is an estimation of errors in resistivity measurements that arise because of the type of electrode material used. Fourteen types of electrodes were tested including metal electrodes, metal-salt-compound (nonpolarizing) electrodes, and one nonmetal electrode, under conditions that are typical of those encountered during geophysical surveys. Measurement errors for resistance and chargeability were estimated using the reciprocity of data from an array of electrodes such as might be used for electric-resistance tomography. The same error analysis was applied to data from a network of high-precision resistors to separate instrument errors from electrode errors. Significant differences were observed in errors produced by different electrode materials. We conclude that the choice of electrode is very important for resistivity or chargeability surveys. Iron, steel (including rebar), lead, and phosphor bronze produced the smallest errors in resistance and chargeability. Aluminum, magnesium, titanium, copper, and zinc produced the largest errors. Stainless steel (alloy 316), tin, and brass performed reasonably well, as did carbon, which was the only nonmetal tested.

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SRIVASTAVA, SN, and S. NIRANJAN. "A transistorized Rocketsonde for measurement of upper atmosphere temperature." MAUSAM 19, no. 2 (May 2, 2022): 217–18. http://dx.doi.org/10.54302/mausam.v19i2.5238.

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This note gives description of & pulse modulated transistorized rocketsonde instrument package, working on 1680 Mc/s for telemetering temperature information from meteorological sounding rockets. Currently used ground equipments like GMD-1 or WBRT-57 can be used to receive the signals. The package is completely transistorized except for the final transmitting stage which has a sub-miniature tube. H.T. battery, however, is not required for this tube. The change in resistance of the thermistor due to variation in tempernture changes the p.r.f. of the modulator between 10 to 200 cps.

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Huff, J. E., and K. R. Shaw. "Measurement of flow resistance of rupture disc devices." Plant/Operations Progress 11, no. 3 (July 1992): 187–200. http://dx.doi.org/10.1002/prsb.720110316.

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Colella, Pietro, Enrico Pons, Riccardo Tommasini, Maria Luisa Di Silvestre, Eleonora Riva Sanseverino, and Gaetano Zizzo. "Fall of Potential Measurement of the Earth Resistance in Urban Environments: Accuracy Evaluation." IEEE Transactions on Industry Applications 55, no. 3 (May 2019): 2337–46. http://dx.doi.org/10.1109/tia.2019.2892680.

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22

Elliott, J. R., M. de Michele, and H. K. Gupta. "Earth Observation for Crustal Tectonics and Earthquake Hazards." Surveys in Geophysics 41, no. 6 (August 28, 2020): 1355–89. http://dx.doi.org/10.1007/s10712-020-09608-2.

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Abstract In this paper, we illustrate some of the current methods for the exploitation of data from Earth Observing satellites to measure and understand earthquakes and shallow crustal tectonics. The aim of applying such methods to Earth Observation data is to improve our knowledge of the active fault sources that generate earthquake shaking hazards. We provide examples of the use of Earth Observation, including the measurement and modelling of earthquake deformation processes and the earthquake cycle using both radar and optical imagery. We also highlight the importance of combining these orbiting satellite datasets with airborne, in situ and ground-based geophysical measurements to fully characterise the spatial and timescale of temporal scales of the triggering of earthquakes from an example of surface water loading. Finally, we conclude with an outlook on the anticipated shift from the more established method of observing earthquakes to the systematic measurement of the longer-term accumulation of crustal strain.

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Schenkel, Clifford J., and H. Frank Morrison. "Electrical resistivity measurement through metal casing." GEOPHYSICS 59, no. 7 (July 1994): 1072–82. http://dx.doi.org/10.1190/1.1443663.

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Methods using dc electrical arrays to measure formation resistivity through casing have relied on approximate forms for the current and potential distributions to derive a simple relationship between the formation resistivity and the transverse resistance calculated from measurements of the potential and its second derivative inside the casing. We have derived a numerical solution for the potentials and their derivatives to examine the accuracy of the approximate forms for casing of finite‐length, annular zones of varying radius, and for vertical discontinuities such as layers or abrupt changes in annular zone radius. For typical conductivity contrasts between the casing and formation, the approximate relationships may be off by as much as 60 percent for long casing and may show variations of 20 to 30 percent as the electrode array moves along the casing. In principle an iterative scheme could be devised to correct the readings if high accuracy was required. The numerical results show that to first order the current flow from the casing is radial, and that all the analytic expressions based on this assumption for evaluating layer resolution and the effects of annular layers are valid. An interesting byproduct of this study has been the discovery that the distortion of the potentials in a nearby well by an annular disk (e.g., an injected steam zone) surrounding the current injection well is greater if the injection well is cased. Crosswell resistivity surveys appear feasible if one of the wells is cased.

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Košťák, B., and E. Avramova-Tačeva. "Method for measurement of contemporary displacement on tectonic faults." Journal of Geodynamics 9, no. 2-4 (July 1988): 119–20. http://dx.doi.org/10.1016/s0264-3707(88)80052-8.

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Cutler, Jonathan M. "Error due to strain measurement in non-principal sections." Tectonophysics 113, no. 1-2 (March 1985): 185–90. http://dx.doi.org/10.1016/0040-1951(85)90116-7.

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26

Shui-Beih, Yu, and Lee Chiungwu. "Geodetic measurement of horizontal crustal deformation in eastern Taiwan." Tectonophysics 125, no. 1-3 (May 1986): 73–85. http://dx.doi.org/10.1016/0040-1951(86)90007-7.

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27

Yin, Changchun, and Ruo Wang. "Power line ground resistance detection using helicopter electromagnetic systems." GEOPHYSICS 80, no. 2 (March 1, 2015): E125—E133. http://dx.doi.org/10.1190/geo2014-0421.1.

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Power line grounding can be a serious concern for the power supply industry. Only a small amount of ground resistance is acceptable because a good electric contact of power line towers with the earth reduces the possibility of the natural hazard associated with lightning. We investigated the possibility of using helicopter-borne electromagnetic (HEM) apparatus to detect the ground resistances of power line towers. Two induction systems were considered: a transmitter-earth-receiver system and a power line loop-earth-receiver system. The transmitter-earth-receiver system built the background signal in the HEM receiver, whereas the power line loop-earth-receiver system produced the signal used for resolving the power line ground resistances. By ignoring the mutual coupling between the two systems, we calculated the induced electromotive forces in the power line loop above which the HEM bird was flown and its two immediate neighbor loops. We replaced other loops along the power line with the Norton-Thevinin equivalence and solved the current flow in the power line loop by the mesh current method. Using the current in the power line loop as induction source, we calculated the electromagnetic responses in the HEM receiver from the power line loop-earth-receiver system. For identification of the poorly grounded towers, we introduced ratios of in-phase and quadrature to signal amplitude and the HEM phase. We evaluated numerical experiments showing that these parameters can well identify power line towers with high ground resistances, and they were insensitive to the flight altitude and direction. Moreover, we also took the catenaries of the power line into consideration so that the elevation differences between towers resulting from rugged mountains could be easily incorporated into the interpretation. We considered vertical coaxial (VCA) and horizontal coplanar (HCP) coil configurations. It was found that the signal for HCP coil has multiple peaks, whereas the VCA coil signal has only a single peak, so we recommend the VCA coil array for power line ground resistance detection. The inversion of synthetic data showed that the power line ground resistances can be resolved from the HEM survey.

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28

Košťák, B., and E. Avramova-Tačeva. "A method for contemporary displacement measurement on a tectonic fault." Journal of Geodynamics 10, no. 2-4 (December 1988): 115–25. http://dx.doi.org/10.1016/0264-3707(88)90018-x.

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29

Corbellini, G., and U. Corbellini. "Definition and measurement of the earth resistance of an electrode covering a large area." European Transactions on Electrical Power 5, no. 3 (September 6, 2007): 173–80. http://dx.doi.org/10.1002/etep.4450050305.

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30

Carter, W. E., and D. S. Robertson. "Very-Long-Baseline Interferometry Applied to Geophysics." Symposium - International Astronomical Union 156 (1993): 133–44. http://dx.doi.org/10.1017/s0074180900173115.

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Very-long-baseline Interferometry (VLBI) has opened for study a broad new spectrum of geophysical phenomena including: direct observation of the tectonic motions and deformations of the Earth's crustal plates, observations of unprecedented detail of the variations in the rotation of the Earth, and direct measurement of the elastic deformations of the Earth in response to tidal forces. These new measurements have placed significant constraints on models of the interior structure of the Earth; for example, measurements of the variations in the Earth's nutation have been shown to be particularly sensitive to the shape of the core-mantle boundary. The VLBI measurements will allow us to construct a global reference frame accurate at the centimeter level. Such a frame will be essential to studying long-term global changes, especially those changes related to sea-level variations as recorded by tide gauge measurements.

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31

Rasol, Mezgeen, Franziska Schmidt, Silvia Ientile, Lucas Adelaide, Boumediene Nedjar, Malal Kane, and Christophe Chevalier. "Progress and Monitoring Opportunities of Skid Resistance in Road Transport: A Critical Review and Road Sensors." Remote Sensing 13, no. 18 (September 17, 2021): 3729. http://dx.doi.org/10.3390/rs13183729.

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Skid resistance is a significant feature that provides consistent traffic safety management for road pavements. An appropriate level of Skid resistance describes the contribution that the pavement surface makes to tire/road friction, and the surface of the road pavement can reduce vehicle operation cost, traffic accidents, and fatalities, particularly in wet conditions. Wet conditions decrease the level of the skid resistance (pavement friction), and this may lead to serious struggles related to driving on the road pavement (e.g., skidding or hydroplaning), which contributes to higher crash rates. The knowledge of skid resistance is essential to ensure reliable traffic management in transportation systems. Thus, a suitable methodology of skid resistance measurement and the understanding of the characterization of the road pavement are key to allow safe driving conditions. This paper presents a critical review on the current state of the art of the research conducted on skid resistance measurement techniques, taking into account field-based and laboratory-based methodologies, and novel road sensors with regard to various practices of skid resistance, factors influencing the skid resistance, the concept of the minimum skid resistance and thresholds. In conclusion, new trends that are relevant to data collection approaches and innovative procedures to further describe the data treatment are discussed to achieve better understanding, more accurate data interoperability, and proper measurement of skid resistance.

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32

Toni, G. "Stability evolution of clayey slopes and measurement modelling of mobilizing shearing resistance." Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere 25, no. 9 (January 2000): 793–97. http://dx.doi.org/10.1016/s1464-1909(00)00103-9.

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33

Borradaile, Graham John, and Mike Stupavsky. "Anisotropy of magnetic susceptibility: Measurement schemes." Geophysical Research Letters 22, no. 15 (August 1, 1995): 1957–60. http://dx.doi.org/10.1029/95gl01910.

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34

Werner, C., J. C. Wyngaard, and S. L. Brantley. "Eddy-correlation measurement of hydrothermal gases." Geophysical Research Letters 27, no. 18 (September 15, 2000): 2925–28. http://dx.doi.org/10.1029/2000gl011765.

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35

Kostiuk, Theodor, Kelly E. Fast, Timothy A. Livengood, Tilak Hewagama, Jeffrey J. Goldstein, Fred Espenak, and David Buhl. "Direct measurement of winds on Titan." Geophysical Research Letters 28, no. 12 (June 15, 2001): 2361–64. http://dx.doi.org/10.1029/2000gl012617.

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36

Burgess, A. B., R. G. Grainger, A. Dudhia, V. H. Payne, and V. L. Jay. "MIPAS measurement of sulphur hexafluoride (SF6)." Geophysical Research Letters 31, no. 5 (March 9, 2004): n/a. http://dx.doi.org/10.1029/2003gl019143.

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37

Renzetti, N. A. "A global positioning measurement system for regional geodesy in the caribbean." Tectonophysics 130, no. 1-4 (November 1986): 61–76. http://dx.doi.org/10.1016/0040-1951(86)90101-0.

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38

Le Guern, Jules, Stéphane Rodrigues, Thomas Geay, Sébastien Zanker, Alexandre Hauet, Pablo Tassi, Nicolas Claude, Philippe Jugé, Antoine Duperray, and Louis Vervynck. "Relevance of acoustic methods to quantify bedload transport and bedform dynamics in a large sandy-gravel-bed river." Earth Surface Dynamics 9, no. 3 (May 27, 2021): 423–44. http://dx.doi.org/10.5194/esurf-9-423-2021.

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Abstract. Despite the inherent difficulties in quantifying its value, bedload transport is essential for understanding fluvial systems. In this study, we assessed different indirect bedload measurement techniques with a reference direct bedload measurement in a reach of a large sandy-gravel-bed river. An acoustic Doppler current profiler (aDcp), the dune tracking method (DTM) and hydrophone measurement techniques were used to determine bedload transport rates by using calibration with the reference method or by using empirical formulas. This study is the first work which attempted to use a hydrophone to quantify bedload rates in a large sandy-gravel-bed river. Results show that the hydrophone is the most efficient and accurate method for determining bedload fluxes in the Loire River. Although further work is needed to identify the parameters controlling self-generated sediment noise, the calibration procedure adopted in this study allows a satisfactory estimation of bedload transport rates. Moreover, aDcp and hydrophone measurement techniques are accurate enough to quantify bedload variations associated with dune migration.

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39

Abbas, M. M., M. J. Glenn, I. G. Nolt, B. Carli, F. Mencaraglia, and M. Carlotti. "Far-infrared measurement of stratospheric carbon monoxide." Geophysical Research Letters 15, no. 2 (February 1988): 140–43. http://dx.doi.org/10.1029/gl015i002p00140.

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40

Ahmadjian, M., D. E. Jennings, M. J. Mumma, F. Espenak, C. J. Rice, R. W. Russell, and B. D. Green. "Infrared spectral measurement of space shuttle glow." Geophysical Research Letters 19, no. 10 (May 22, 1992): 989–92. http://dx.doi.org/10.1029/92gl00051.

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41

Brozena, John M., Mary F. Peters, and Rene Forsberg. "Airborne measurement of absolute sea-surface heights." Geophysical Research Letters 20, no. 9 (May 7, 1993): 875–78. http://dx.doi.org/10.1029/93gl00864.

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42

Qu, Xin Bo, Bi Hua Zhou, Ning Sheng Cao, Ya Peng Fu, and Xiao Gang Huang. "The Analysis of Transient Grounding Resistance of Portable Horizontal Grid Earth Electrodes." Applied Mechanics and Materials 347-350 (August 2013): 1753–57. http://dx.doi.org/10.4028/www.scientific.net/amm.347-350.1753.

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Based on current situation of mobile equipments earth devices, a new type of portable horizontal grid earth electrode has been designed. With the impulse ground measurement system, different number of earth electrodes responses to double exponential pulse current have been tested on cement grounds. Impulse waves of voltage and current have been gotten by experiments, and the curve of Transient Grounding Resistance (TGR) can be calculated. The analysis of discharging capacity of horizontal grid earth electrodes in time domain has great significance in the design of mobile equipments earth devices.

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43

Brodrick, P. G., L. D. L. Anderegg, and G. P. Asner. "Forest Drought Resistance at Large Geographic Scales." Geophysical Research Letters 46, no. 5 (March 2019): 2752–60. http://dx.doi.org/10.1029/2018gl081108.

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44

Fuji-ta, Kiyoshi, Tomoo Katsura, Takuya Matsuzaki, Masahiro Ichiki, and Tomoyuki Kobayashi. "Electrical conductivity measurement of gneiss under mid- to lower crustal P–T conditions." Tectonophysics 434, no. 1-4 (April 2007): 93–101. http://dx.doi.org/10.1016/j.tecto.2007.02.004.

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45

Kunde, V. G., J. C. Brasunas, W. C. Maguire, J. R. Herman, S. T. Massie, M. M. Abbas, L. W. Herath, and W. A. Shaffer. "Measurement of nighttime stratospheric N2O5from infrared emission spectra." Geophysical Research Letters 15, no. 11 (October 1988): 1177–80. http://dx.doi.org/10.1029/gl015i011p01177.

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46

Bottomley, Richard, and Derek York. "Age measurement of the submarine montagnais impact crater." Geophysical Research Letters 15, no. 12 (November 1988): 1409–12. http://dx.doi.org/10.1029/gl015i012p01409.

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47

Hirata, Kenji, and Toshitaka Baba. "Transient thermal response in ocean bottom pressure measurement." Geophysical Research Letters 33, no. 10 (May 2006): n/a. http://dx.doi.org/10.1029/2006gl026084.

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48

Torr, Marsha R., D. G. Torr, and P. G. Richards. "N(2P) in the dayglow: Measurement and theory." Geophysical Research Letters 20, no. 6 (March 19, 1993): 531–34. http://dx.doi.org/10.1029/92gl02180.

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49

Campos, T. L., A. J. Weinheimer, J. Zheng, D. D. Montzka, J. G. Walega, F. E. Grahek, S. A. Vay, et al. "Measurement of NO and NOyemission indices during SUCCESS." Geophysical Research Letters 25, no. 10 (May 15, 1998): 1713–16. http://dx.doi.org/10.1029/97gl03480.

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50

Nakamura, M., H. Noda, I. Yoshikawa, N. Iwagami, M. Hirahara, M. Yamamoto, and S. Fukao. "DC electric field measurement in the SEEK Campaign." Geophysical Research Letters 25, no. 11 (June 1, 1998): 1777–80. http://dx.doi.org/10.1029/97gl03715.

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