Abstract One of the main goals interpretation magnetic data is imaging boundaries subsurface structures. In this study, a new edge detector called improved horizontal tilt angle (impTDX) has been introduced and tested on synthetic measured data. The filter exhibits high efficiency not only in detecting sources, but also determining sources from different depth levels. impTDX produces more precise sharper boundaries, increases discernibility neighboring anomalies, advantage avoiding creation...

This study investigates the presence and spatial extent of saline water seawater intrusion in Subiya Peninsula, Kuwait, a region designated for establishment new Silk City. We collected transient electromagnetic (TEM) data at 63 stations using coincident loop setup on regional, as well local, scale. The were analyzed through conventional 1D inversion techniques, including Occam Levenberg–Marquardt methods, to create detailed resistivity models subsurface. Our findings indicate significant...

Over the last two decades, controlled source (CS) electromagnetic (EM) methods using an extended frequency range from 1-1000 kHz have been developed. Controlled sources complement Radio-magnetotellurics (RMT) method by providing a wider range, greater depth of investigation and more stable responses. In addition, they remain operational even without radio antennas in vicinity measurement area. While initially CS-/RMT was originally considered only far-field conditions, it has recently to...

The present study was designed to give a clear and comprehensive understanding of the structural situation in Sohag region surrounding area by applying several edge detectors aeromagnetic data. In this research, International Geomagnetic Reference Field (IGRF) values were removed from data obtained then reduced north magnetic pole (RTP). A combination different applied determine boundaries sources. good correlation noticed between these techniques, indicating that their integration can...

Abstract Electrical resistivity tomography (ERT) and ground magnetic surveys were applied to characterize an old uncontrolled landfill in a former exploited sand gravel quarry area the north-west of city Cologne, Germany. The total field its vertical gradient recorded using proton precession magnetometer cover about 43,250 m 2 . data transferred frequency domain then reduced north pole. amplitude analytical signal was calculated define materials within outside landfill. Eight ERT profiles...

A radio magnetotelluric (MT) field data set, acquired in scalar mode, over a buried waste site has been successfully analyzed using 3D MT inversion scheme nonlinear conjugate gradients. The results of this analysis demonstrate the utility where more than 4800 points collected on multiple measurement profiles have inverted simultaneously. resulting image clearly detects waste; when receiver cross pit boundaries, maps lateral extent pit. However, base is poorly resolved, and depends upon...

ABSTRACT An algorithm for the two‐dimensional (2D) joint inversion of radiomagnetotelluric and direct current resistivity data was developed. This can be used 2D apparent sets collected by multi‐electrode systems various classical electrode arrays (Wenner, Schlumberger, dipole‐diplole, pole‐dipole) measurements jointly. We use a finite difference technique to solve Helmoltz Poisson equations methods respectively. A regularized with smoothness constrained stabilizer employed invert both sets....

The marine differential electric dipole (DED) is applied for the first time to study a subseafloor groundwater body in coastal region of Bat Yam, Israel. Previous long-offset transient electromagnetic applications detected this freshwater underneath Mediterranean seafloor. We have novel DED method environment further investigate natural phenomenon. main objectives are locate freshwater-seawater interface at western aquifer edge and identify mechanism controlling occurrence beneath acquired...

The transition toward renewable energies demands a secure supply of critical raw materials and requires efficient noninvasive methods for deep earth resource exploration. novel, electromagnetic (EM) sounding the mineral exploration semi-airborne EM (semi-AEM) concept aims at resources down to depth 1 km. Here, we evaluate large-scale semi-AEM study in graphite mining district eastern Bavaria, Germany. derived 3D model is based on approximately 70,000 complex-valued data points recorded using...

ABSTRACT Lake sediments may serve as archives on paleoclimatic fluctuations, geomagnetic field variations and volcanic activities. Holzmaar in Eifel/Germany is a maar lake its lacustrine provide proxy data. Therefore, knowledge about the geometry and, especially, thickness of very important for determining an optimum drilling location studies. We have developed floating in‐loop transient electromagnetic method set up (Float‐transient method) with transmitter receiver size 18 × m 2 6...

We present a new approach for 2-D magnetotelluric forward numerical modelling in contrast to traditional methods like finite elements or differences. The method used solving the partial differential equations is based on mesh-free technique which does not need an underlaying mesh grid. use Meshless Local Petrov–Galerkin (MLPG) combination with radial basis functions simulate response of given conductivity model plane-wave source. compare solution known simulation programs and simple...

Water-covered areas may lead to gaps in surface electromagnetic surveys, causing reduced resolution and, as a consequence, increased uncertainty derived subsurface models. We have evaluated boat-towed floating central loop time-domain technique that mitigates this problem. It facilitates obtaining data with spatial sampling density, which is rarely possible standard instrumentation on land, and it only requires moderate logistical effort. A unique field study shallow volcanic lake...

ABSTRACT A new method for the 2D inversion of induced polarization (IP) data in time domain has been developed. The entire IP transients were observed and inverted into Cole‐Cole earth models, including resistivity, chargeability, relaxation frequency constant. Firstly, a modified 1D time‐domain electromagnetic algorithm was used to calculate response layered polarizable ground. transient signals then using Marquardt derive parameters each layer. However, model calculations showed that EM...

ABSTRACT A new radiomagnetotelluric (RMT) instrument has been developed that can record time series of electric and magnetic fields in the frequency range from 10 kHz to 1 MHz. Military civilian radio stations broadcasting this are used as transmitters. Transfer functions (e.g., apparent resistivities phases a function frequency) determined by spectral analysis using newly processing software. The transfer presented here first ones ever at frequencies above 300 they lead better resolution...

Abstract Bülent Tezkan, Johannes B. Stoll, Rainer Bergers and Hannah Großbach report on a recent pilot project to prove the feasibility of unmanned aircraft systems for carrying out aeromagnetic surveys.

We have compared structured and unstructured grid-based 2D inversion algorithms for magnetotelluric (MT) radiomagnetotelluric (RMT) data in terms of speed accuracy. developed a new algorithm MT RMT by using finite-element (FE) method that uses triangle grids. compare the results our with those conventional algorithm, which either FE or finite-difference (FD) numerical solution technique. The imaging surface topography underground resistivity structures requires fewer elements than use FD...

ABSTRACT We compare selected marine electromagnetic methods for sensitivity to the presence of relatively thin resistive targets (e.g., hydrocarbons, gas hydrates, fresh groundwater, etc.). The study includes conventional controlled‐source method, recently introduced transient prospecting with vertical electric lines and novel circular dipole which is still in stage theoretical development. comparison based on general physical considerations, analytical (mainly asymptotic) analysis, rigorous...

ABSTRACT In the framework of Deep Electromagnetic Soundings for Mineral Exploration project, we conducted ground‐based long‐offset transient‐electromagnetic measurements in a former mining area eastern Thuringia, Germany. The large‐scale survey resulted an extensive dataset acquired with multiple high‐power transmitters and high number electric magnetic field receivers. recorded data exhibit quality over several decades time orders magnitude. Although obtained subsurface models indicate...