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Exploration Geophysics
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  The Journal of the Australian Society of Exploration Geophysicists
 
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Exploration Geophysics presents case histories, advances in data interpretation, and theoretical developments in applied geophysics. More

Managing Editor: Mark Lackie

 
 
 

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Published online 25 March 2015
Benefits of using multi-component transmitter–receiver systems for determining geometrical parameters of a dipole conductor from single-line anomalies 
Jacques K. Desmarais and Richard S. Smith

We show the advantages of using multi-component transmitter–receiver systems for determining the geometry of a dipole conductor. We find that single transmitter systems are unable to resolve the orientation of an axially symmetric conductor and subsequently determine which measurements from a multi-component transmitter–receiver system are critical to address this problem.

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Published online 25 March 2015
Decomposing the electromagnetic response of magnetic dipoles to determine the geometric parameters of a dipole conductor 
Jacques K. Desmarais and Richard S. Smith

A novel automatic data interpretation algorithm is presented for modelling airborne electromagnetic (AEM) data acquired over resistive environments, using a single-component transmitter, where the position and orientation of a dipole conductor is allowed to vary in three dimensions. This algorithm is tested on both synthetic and field data.

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Published online 13 March 2015
Frequency-wavenumber implementation for P- and S-wave separation from multi-component seismic data 
Zhiyuan Li, Xiaona Ma, Chao Fu, Bingluo Gu and Guanghe Liang

This paper presents a modified separation equation of P- and S-waves for multi-component seismic data in the frequency-wavenumber domain. The equation can be applied to the seismic data which are recorded on the laterally heterogeneous free surface.

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Published online 26 February 2015
Depth and shape solutions from second moving average residual magnetic anomalies 
El-Sayed M. Abdelrahman, Khalid S. Essa, Tarek M. El-Araby and Eid R. Abo-Ezz

We have developed an efficient method to simultaneously determine the depth and shape of a buried structure from second moving average residual magnetic anomalies. The method is based on computing the standard deviation of the depths for each shape factor, and was applied to synthetic and field data.

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Published online 24 February 2015
Monitoring CO2 drainage and imbibition in a heterogeneous sandstone using both seismic velocity and electrical resistivity measurements 
Jongwook Kim, Myung Jin Nam and Toshifumi Matsuoka

Seismic velocity and electrical resistivity were measured simultaneously to monitor the behaviour of carbon dioxide (CO2) during CO2 drainage and imbibition within a heterogeneous, clay-containing Tako sandstone sample. Employing Archie’s equation and the Gassmann fluid-substitution equation, electrical resistivities and P-wave velocities were analysed respectively and interpreted to evaluate CO2 saturation.

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Published online 24 February 2015
3D unconstrained and geologically constrained stochastic inversion of airborne vertical gravity gradient data 
Euloge Budet Tchikaya, Michel Chouteau, Pierre Keating and Pejman Shamsipour

This article presents an inversion tool for airborne gravity gradient data that yields a 3D density model using stochastic methods i.e. cokriging and conditional simulation. This method uses geostatistical properties of the measured gravity gradient to estimate a 3D density model. Applications to modelled and survey data demonstrate the performance of the method.

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Published online 19 February 2015
Drill-rig noise suppression using the Karhunen-Loéve transform for seismic-while-drilling experiment at Brukunga, South Australia 
Baichun Sun, Andrej Bóna, Binzhong Zhou, Andrew King, Christian Dupuis and Anton Kepic

To overcome the challenge of surface wave interference generated from drill rigs for seismic-while-drilling, we compare two wavefield separation methods: (1) the Karhunen-Loéve (KL) transform and (2) the fk filter. The results show that drill-rig noise can be effectively suppressed in the correlation domain.

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Published online 30 January 2015
Calculation of gravity due to a vertical cylinder using a spherical harmonic series and numerical integration 
Sung-Ho Na, Hyoungrea Rim, Young-Hong Shin, Mutaek Lim and Yeong-Sue Park

In this paper, the spherical harmonic series of the gravitational potential and its gravity field due to a right vertical cylinder was developed. This series can be used at far and intermediate regions, and it is fast and accurate, using only a few terms.

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Published online 15 January 2015
Direct simulation Monte Carlo method with a focal mechanism algorithm 
Asep Nur Rachman, Tae Woong Chung, Kazuo Yoshimoto and Sukyoung Yun

To simulate the observation of the radiation pattern of an earthquake, the direct simulation Monte Carlo method is modified by implanting a focal mechanism algorithm. The modified method shows more reliable results compared to those of the original one, for events with more than 12 recorded stations.

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Published online 13 January 2015
Imaging tilted transversely isotropic media with a generalised screen propagator 
Sung-Il Shin, Joongmoo Byun and Soon Jee Seol

We expand the vertical transversely isotropic generalised screen propagator into a tilted transversely isotropic generalised screen propagator (TTI-GSP) by adopting tilted coordinates. The validity of the developed algorithm has been tested by increasing the accuracy of wide-angle propagation in TTI-GSP with high-order expansion of the velocity perturbation.

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Published online 05 January 2015
Identification of leachate from livestock mortality burial using electrical resistivity and small-loop EM survey: case history 
Sung-Ho Song, In-Ky Cho and Kwang-Jun Choi

A small-loop EM survey and electrical resistivity survey were applied to a carcass disposal site to delineate the burial shape and extent of leachate arising from the burial. The small-loop EM survey was adequate for a reconnaissance survey of the burial zone and the resistivity survey was useful for quantitatively interpreting the pathway of leachate flows in the site.

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Published online 24 December 2014
Integrated interpretation of overlapping AEM datasets achieved through standardisation 
Camilla C. Sørensen, Tim Munday and Graham Heinson

Combining resistivity-depth models obtained from the inversion of airborne electromagnetic data can be challenging, but spatially coherent resistivity-depth images of the ground can assist geological interpretations. We use ground EM data to standardise AEM data so as to be able to combine overlapping AEM datasets acquired with different systems.

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Published online 19 December 2014
A modified excitation amplitude imaging condition for prestack reverse time migration 
Bingluo Gu, Youshan Liu, Xiaona Ma, Zhiyuan Li and Guanghe Liang

We propose a process to effectively use the modified shortest path method for extracting the maximum amplitude around the first-arrival events. Then, the excitation amplitude imaging condition is applied to obtain a continuous and clear migration image. Numerical tests show that the improvement is feasible and effective in complex-structure media.

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Published online 18 December 2014
Kirchhoff prestack migration using the suppressed wave equation estimation of traveltime (SWEET) algorithm in VTI media 
Ho Seuk Bae, Wookeen Chung, Jiho Ha and Changsoo Shin

This paper examines anisotropic prestack Kirchhoff migration using the pseudo-acoustic wave equation in a vertical transversely isotropic (VTI) medium. Both amplitudes and traveltimes were calculated efficiently for migration using the suppressed wave equation estimation of traveltime (SWEET) algorithm.

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Published online 17 December 2014
Estimating primaries from passive seismic data 
Hao Cheng, De-Li Wang, Fei Feng and Heng Zhu

Passive seismic sources can generally be divided into transient and noise sources. We compare the primaries estimated from passive seismic data using transient sources and noise sources, and analyse the characteristics of the estimated primaries obtained from the two sets of passive seismic data.

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Published online 15 December 2014
Case studies of geophysical imaging for road foundation design on soft soils and embankment risk assessment 
Robert J. Whiteley, Richard B. Kelly and Simon B. Stewart

The application of both geophysical imaging and geotechnical testing in road foundation design is a cost-effective enhancement for site characterisation of soft soils and for risk assessment of potentially unstable embankments. The incorporation of geophysics allows concentration on fewer but higher quality soil probings and geotechnical boreholes.

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Published online 08 December 2014
Laboratory modelling of self-potential anomalies due to spherical bodies 
Mohamad Sadegh Roudsari and Ali Beitollahi

This paper presents the experimental design and modelling of self-potential anomalies produced by a sphere-shaped copper–zinc source using a water tank and polarising electrodes. Self-potentials were measured by placing the sphere at a given depth in a rectangular glass tank filled with water.

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Published online 25 November 2014
Deblending using a space-varying median filter 
Yangkang Chen

In this paper, I propose to use a space-varying median filter (SVMF) to remove blending noise. I demonstrate that this filtering method preserves more useful seismic reflection than does the conventional version of a median filter (MF). SVMF can be regionally adaptive, instead of rigidly using a constant window length through the whole profile for filtering.

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Published online 13 November 2014
mCSEM inversion for CO2 sequestration monitoring at a deep brine aquifer in a shallow sea 
Seogi Kang, Kyubo Noh, Soon Jee Seol and Joongmoo Byun

We developed an efficient 2.5D mCSEM inversion algorithm based on an accurate forward modelling algorithm and the judicious incorporation of a priori information into our inversion scheme. We demonstrated the successful recovery of resistivity distributions of the injected CO2 from the deep brine aquifer model in the shallow sea.

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Published online 12 November 2014
Magnetic depths to basalts: extension of spectral depths method 
Roger Clifton

By assuming that anomalies in a TMI grid arise from thin magnetic layers, spectral depth estimates to one or more equivalent magnetic layers may be obtained repeatedly across large areas. A general formula is derived for the purpose and demonstrated on the TMI grid of the Northern Territory.

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Published online 08 September 2014
Estimation of surface-wave phase velocity from microtremor observation using an array with a reference station 
Hiroaki Yamanaka, Kei Kato, Kosuke Chimoto and Seiji Tsuno

An interferometric procedure for Rayleigh wave phase velocities from cross correlations of microtremors in an array with a reference station is investigated in this study. After identifying dispersive Rayleigh waves, semblance analysis of the cross correlations was carried out to estimate phase velocities for fundamental and higher-mode Rayleigh waves.

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Published online 04 September 2014
Inverse AVO problem for a stack of layers 
Liliya Malovichko

The problem of estimating thin layered model parameters by amplitude variation with offset (AVO) inversion of prestack seismic data has been studied. An algorithm for solving the prestack inverse AVO problem in the case of multilayered media has been derived. Numerical examples show the accuracy and efficiency of the method.

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Published online 06 August 2014
Accelerating seismic interpolation with a gradient projection method based on tight frame property of curvelet 
Jingjie Cao, Yanfei Wang and Benfeng Wang

A gradient projection method for seismic interpolation based on the tight frame property of curvelet transform is proposed. Some smooth L1 norm functions were analysed, and the Huber function was chosen to replace the L1 norm. The tight frame property of the curvelet transform is utilised to improve the computational efficiency.

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Published online 29 July 2014
An overview of a highly versatile forward and stable inverse algorithm for airborne, ground-based and borehole electromagnetic and electric data 
Esben Auken, Anders Vest Christiansen, Casper Kirkegaard, Gianluca Fiandaca, Cyril Schamper, Ahmad Ali Behroozmand, Andrew Binley, Emil Nielsen, Flemming Effersø, Niels Bøie Christensen, Kurt Sørensen, Nikolaj Foged and Giulio Vignoli

We present an overview of a mature and general algorithm for inversion of most electromagnetic and geoelectrical data, ground-based and airborne. The implementation uses a 1D formulation for electromagnetics and MRS responses, geoelectric responses are 1D and 2D, and the 3D sheet’s response implements an overburden of varying thickness and resistivity.

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Published online 17 July 2014
First application of airborne gravity to oil exploration in the Shengli oil province, eastern China 
Wenyong Li, Jianxin Zhou, Yanxu Liu and Jianchun Xu

An airborne gravity survey was successfully conducted over the onshore and offshore regions of the south-west Bohai Sea. The derived Bouguer gravity data and inversed results correlate well with features such as known faults, swells, sags, and oilfields identified by earlier seismic survey and drilling data.

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Published online 26 June 2014
Edge enhancement of potential field data using an enhanced tilt angle 
Xu Zhang, Peng Yu, Rui Tang, Yang Xiang and Chong-Jin Zhao

An edge-detection technique for the enhancement of potential field data, which is based on the tilt angle of the first order vertical derivative of the total horizontal gradient, is presented. The new filter clearly enhances the edges of superimposed sources sharply and generates more subtle detail.

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Published online 03 June 2014
Comments on: Christensen, N., and Lawrie, K., 2012. Resolution analyses for selecting an appropriate airborne electromagnetic (AEM) system, Exploration Geophysics, 43, 213–227 
Adam Smiarowski and Shane Mulè

The AEM in-line component is added to the posterior model covariance matrix analysis done by Christensen and Lawrie, who estimated resolution of data in an inversion program. They compared two AEM systems: SkyTEM and CGG’s TEMPEST™. Here, we clarify points made about TEMPEST™ and extend the analysis to include the in-line component.

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Published online 03 June 2014
Response to comments by Adam Smiarowski and Shane Mulè on: Christensen, N., and Lawrie, K., 2012. Resolution analyses for selecting an appropriate airborne electromagnetic (AEM) system, Exploration Geophysics, 43, 213–227 
Niels B. Christensen and Ken Lawrie

We analyse and compare the resolution improvement that can be obtained from including x-component data in the inversion of AEM data from the SkyTEM and TEMPEST systems. Except for the resistivity of the bottom layer, the SkyTEM system, even without including x-component data, has the better resolution of the parameters of the analysed models.

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Published online 14 May 2014
Radiowave imaging research (RIM) for determining the electrical conductivity of the rock in borehole section OL-KR4-OL-KR10 at Olkiluoto, Finland 
Arto Korpisalo and Eero Heikkinen

The radiowave imaging method (RIM) was tested in the possible area for a repository of spent nuclear fuel in Finland to reveal the properties of granitic bedrock. The detected low and high resistivity zones and their apparent shapes and orientations are in fair agreement with geological and other geophysical results.

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Published online 13 May 2014
Changes in P-wave velocity with different full waveform sonic transmitter centre frequency 
Majed Almalki, Brett Harris and J. Christian Dupuis

We have studied the concept of apparent P-wave dispersion and its implications in shallow, moderately consolidated to unconsolidated sandstones. Although quantitative results of apparent P-wave dispersion were difficult to obtain from the field data, it is reasonably clear that small-scale structures are significant factors in determining variations in velocity dispersion.

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Published online 30 April 2014
Implementation of adaptive edge-preserving smoothing regularisation technique for simultaneous multi-frequency full waveform inversion 
Yunhui Park and Sukjoon Pyun

An adaptive smoothing regularisation method for full waveform inversion is proposed. The proposed regularisation method is designed using the local slope and implemented in the form of a preconditioning filter for pure-gradient-based full waveform inversion. It can yield more reliable and precise inverted results compared with conventional regularisation.

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Published online 22 April 2014
Memoryless quasi-Newton (MLQN) method for 2D acoustic full waveform inversion 
Cai Liu, Fengxia Gao, Xuan Feng, Yang Liu and Qianci Ren

In this paper, a memoryless quasi-Newton (MLQN) method is applied in full waveform inversion to invert velocity from surface seismic data for the first time. This method can attain acceptable results with low computation cost and small memory storage requirements. Synthetic model tests show that the MLQN method is feasible and reliable.

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Published online 16 April 2014
Comparison of numerical dispersion in acoustic finite-difference algorithms 
Wen-Quan Liang, Yan-Fei Wang and Chang-Chun Yang

Different methods were developed to suppress the grid dispersion in numerical simulation of the acoustic wave equation. This paper compares the performance of these methods in the space and time–space domains. Dispersion analysis and numerical simulation indicate that a linear method without iteration performs comparably to the optimised methods.

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Published online 09 April 2014
Iterative reweighted least M-estimate AVO inversion 
Yang Liu, Jiashu Zhang and Guangmin Hu

In this paper, an IRLM algorithm which uses Hampel’s three-part redescending M-estimate function as the misfit measure is proposed for robust AVO inversion. By combining the advantages of the Huber norm and biweight norm, the proposed IRLM algorithm performs better in the complex noise environment.

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Published online 18 March 2014
Gaussian beam prestack depth migration in heterogeneous transversely isotropic media 
Jianguang Han and Yun Wang

Based on anisotropic kinematic and dynamic ray tracing systems, an anisotropic Gaussian beam prestack depth migration method for P-wave data in transversely isotropic media is presented in this paper. Tests of synthetic and field seismic data demonstrate that the method is accurate and efficient.

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blank image Exploration Geophysics
Volume 46 Number 1 2015
6th International Conference in Airborne Electromagnetics (AEM 2013)

 
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Table of Contents 
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6th International Conference in Airborne Electromagnetics (AEM 2013) 
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Aaron Davis
pp. 1-2

This special issue of Exploration Geophysics comprises papers from the 6th International Conference in Airborne Electromagnetics (AEM 2013) held in South Africa, and showcases the latest ideas and advancements in the discipline of airborne electromagnetic geophysics.

 
 

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Developing an efficient modelling and data presentation strategy for ATDEM system comparison and survey design 
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Magdel Combrinck
pp. 3-11

A proposal to simplify the display of ATDEM responses through the concept of a three-dimensional signal:noise nomo-volume is presented. It contains the signal:noise values of all system time channels and components for various target depths and conductances integrated into a single interactive three-dimensional image.

 
  
 

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3D-spectral CDIs: a fast alternative to 3D inversion? 
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James Macnae
pp. 12-18

Spectral 3D approximations of the EM response can efficiently model vortex induction and current gathering for simple geological target geometries. This paper presents results of a spectral model fitting algorithm to automatically pick, locate and define a sulphide target from VTEM data at the Forrestania test range, Western Australia.

 
  
 

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The analysis of ZTEM data across the Humble magnetic anomaly, Alaska 
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Daniel Sattel and Ken Witherly
pp. 19-26

ZTEM data acquired across a magnetic anomaly of almost 30 000 nT were analysed for the presence of a magnetic gradient response and the effects from elevated magnetic susceptibilities. Modelling results indicate distortions in the conductivity structure recovered by 3D inversion when elevated magnetic susceptibility values are ignored during the inversion.

 
  
 

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Regional TEMPEST survey in north-east Namibia 
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Geoffrey Peters , Gregory Street , Ivor Kahimise and David Hutchins
pp. 27-35

A regional scale low-cost TEMPEST208 survey in north-east Namibia has provided a geo-electric map of the area, including an indication of Kalahari cover thickness. While there are limitations in terms of detail and depth penetration, the results will assist explorers in selecting areas of shallow cover to reduce costs.

 
  
 

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Helicopter EM (ZTEM–VTEM) survey results over the Nuqrah copper–lead–zinc–gold SEDEX massive sulphide deposit in the Western Arabian Shield, Kingdom of Saudi Arabia 
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Jean M. Legault , Carlos Izarra , Alexander Prikhodko , Shengkai Zhao and Emad M. Saadawi
pp. 36-48

Magnetic and electromagnetic (EM) results from both time-domain (VTEM and AFMAG (ZTEM) helicopter EM surveys are compared over the Nuqrah sedimentary exhalative (SEDEX) massive sulphide deposit in Saudi Arabia. The magnetic and EM data map major controlling structures but only the EM surveys are able to define the Nuqrah deposits.

 
  
 

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MULTIPULSE – high resolution and high power in one TDEM system 
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Tianyou Chen , Greg Hodges and Philip Miles
pp. 49-57

The MULTIPULSE technology airborne TEM system transmits a high power pulse and low power pulse(s) (trapezoid or square) within a half-cycle. The high power pulse ensures good depth of exploration and the low power pulse allows higher near-surface resolution and better sensitivity to weak conductors as confirmed by field results.

 
  
 

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Geobandwidth: comparing time domain electromagnetic waveforms with a wire loop model 
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Greg Hodges and Tianyou Chen
pp. 58-63

The effect of time domain EM waveform, power and receiver sampling times are effectively compared for a wide range of time constants using a wire loop conductor model. Peak time constant and equivalent frequency can be determined analytically or numerically. Arbitrary waveforms can be modelled as a sum of simple short ramps.

 
  
 

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Not extinct yet: innovations in frequency domain HEM triggered by sea ice studies 
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Andreas A. Pfaffhuber and Stefan Hendricks
pp. 64-73

Operational use of frequency domain HEM for sea ice thickness mapping was the driving force for developing new purpose-designed systems. We present improvements in decreasing noise levels by one to two orders of magnitude, and implemented control signals to eliminate system drift. Ground tests and airborne field data confirmed the achievement of these goals.

   |        Open Access Article
 

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Airborne electromagnetic modelling options and their consequences in target definition 
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Alan Yusen Ley-Cooper , Andrea Viezzoli , Julien Guillemoteau , Giulio Vignoli , James Macnae , Leif Cox and Tim Munday
pp. 74-84

Given the range of geological conditions under which airborne EM surveys are conducted, there is an expectation that 2D and 3D methods used to extract models of geological significance would be favoured over 1D inversion and transforms. We analyse data from the Musgrave province, South Australia, used for mineral and for hydro-geological prospecting.

 
  
 

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Modelling an arbitrarily oriented magnetic dipole over a homogeneous half-space for a rapid topographic correction of airborne EM data 
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Julien Guillemoteau , Pascal Sailhac and Mickael Behaegel
pp. 85-96

In mountainous areas, the airborne electromagnetic system can be at an angle with regard to the ground. We analyse how the data and the eddy current are affected in such a context. We also suggest a simple correction for the data and for the sensitivity function that reduces topography effects.

 
  
 

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New developments in AEM discrete conductor modelling and inversion 
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Marc A. Vallée
pp. 97-111

In the last 20 years, sphere and plate models have been integrated in parametric inversion programs which are used today for interactive interpretation of airborne electromagnetic surveys on powerful workstations. Different problems encountered in the implementation and application of these models are discussed and a case history from Abitibi, Canada, is presented.

 
  
 

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Rapid approximate inversion of airborne TEM 
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Peter K. Fullagar , Glenn A. Pears , James E. Reid and Ralf Schaa
pp. 112-117

Two algorithms have been developed to perform rapid approximate 3D inversion of airborne TEM. VPem1D performs 1D inversion at each data location above a 3D model. Interpretation of cover thickness is a natural application. VPem3D performs 3D inversion of resistive limit data. Conversion to resistive limits delivers a massive increase in speed. Both programs can operate on geological models to foster integrated interpretation.

 
  
 

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Modelling the superparamagnetic response of AEM data 
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Daniel Sattel and Paul Mutton
pp. 118-129

VTEM data flown at different system elevations across a known sulphide body and surface cover with elevated superparamagnetic (SPM) properties were analysed. The results indicate that SPM responses can be distinguished from deep conductor responses if the vertical AEM gradient is measured, with EM sensors being offset vertically by 2–40 m.

 
  
 

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Using the in-line component for fixed-wing EM 1D inversion 
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Adam Smiarowski
pp. 130-135

In conductive areas, the in-line component of an offset transmitter–receiver EM system can be more sensitive to the near-surface than the vertical component. Using estimated noise levels, this paper calculates the expected uncertainty on the inverted parameters of a bathymetry model and compares this to inversion results from field data.

 
  
 

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Extending the range of time constants recorded by the SPECTREM AEM system 
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Peter B. Leggatt
pp. 136-139

The Spectrem AEM transmitter has no off-time; secondary signals are recorded at the same time as the transmitter primary. By assuming the secondaries have decayed away by the last window, the signal value is used as an estimate of the primary. The result is underestimation of the secondary amplitudes if the target is highly conductive. This paper describes a method to compute a better estimate of the primary amplitude.

 
  
 

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These articles have been peer reviewed and accepted for publication. They are still in production and have not been edited, so may differ from the final published form.

    EG14093  Accepted 12 March 2015
    The distortion tensor of magnetotellurics: a tutorial on some properties
    Frederick Lilley
    Abstract


    EG15020  Accepted 05 March 2015
    HIGH LATERAL RESOLUTION EXPLORATION USING SURFACE WAVES FROM NOISE RECORDS
    Francisco Jose Chávez-García, Toshiaki Yokoi
    Abstract


    EG15019  Accepted 03 March 2015
    Microtremor response of the Cheongcheon dam in Korea
    Ki Young Kim, Young-gyu Park
    Abstract


    EG14050  Accepted 08 June 2014
    Errata for Clark, D.A., 2012. New methods for interpretation of magnetic vector and gradient tensor data I: eigenvector analysis and the normalised source strength. Exploration Geophysics, 43, 267–282, http://dx.doi.org/10.1071/EG12020.
    David Clark
    Abstract


4


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Rank Paper Details
1. Published 5 September 2014
Optimised edge detection filters in the interpretation of potential field data

Lili Li, Danian Huang, Liguo Han and Guoqing Ma

2. Published 28 November 2014
Methods for determining remanent and total magnetisations of magnetic sources – a review

David A. Clark

3. Published 14 March 2014
Grounded electrical-source airborne transient electromagnetics (GREATEM) survey of Aso Volcano, Japan

Hisatoshi Ito, Hideshi Kaieda, Toru Mogi, Akira Jomori and Youichi Yuuki

4. Published 5 September 2014
Prediction and removal of rotation noise in airborne EM systems

Terence Kratzer and James Macnae

5. Published 28 November 2014
Practical considerations: making measurements of susceptibility, remanence and Q in the field

Phillip W. Schmidt and Mark A. Lackie

6. Published 14 March 2014
Three-dimensional resistivity modelling of grounded electrical-source airborne transient electromagnetic (GREATEM) survey data from the Nojima Fault, Awaji Island, south-east Japan

Sabry Abd Allah, Toru Mogi, Hisatoshi Ito, Akira Jymori, Youichi Yuuki, Elena Fomenko, Kenzo Kiho, Hideshi Kaieda, Koichi Suzuki and Kazuhiro Tsukuda

7. Published 5 September 2014
Bathymetry, electromagnetic streamlines and the marine controlled source electromagnetic method

Andrew Pethick and Brett Harris

8. Published 28 November 2014
Mapping pollution and coastal hydrogeology with helicopterborne transient electromagnetic measurements

Niels B. Christensen and Max Halkjær

9. Published 28 November 2014
Least squares staggered-grid finite-difference for elastic wave modelling

Lei Yang, Hongyong Yan and Hong Liu

10. Published 5 September 2014
A description of seismic amplitude techniques

James Shadlow

11. Published 28 November 2014
Evaluation of structural and geological factors in orogenic gold type mineralisation in the Kervian area, north-west Iran, using airborne geophysical data

Alireza Almasi, Alireza Jafarirad, Hasan Kheyrollahi, Mana Rahimi and Peyman Afzal

12. Published 30 May 2014
A combinatorial filtering method for magnetotelluric time-series based on Hilbert–Huang transform

Jianhua Cai

13. Memoryless quasi-Newton (MLQN) method for 2D acoustic full waveform inversion

Cai Liu, Fengxia Gao, Xuan Feng, Yang Liu and Qianci Ren

14. Published 30 May 2014
Perfectly matched layer on curvilinear grid for the second-order seismic acoustic wave equation

Sanyi Yuan, Shangxu Wang, Wenju Sun, Lina Miao and Zhenhua Li

15. Edge enhancement of potential field data using an enhanced tilt angle

Xu Zhang, Peng Yu, Rui Tang, Yang Xiang and Chong-Jin Zhao

16. Published 14 March 2014
Radiation monitoring using an unmanned helicopter in the evacuation zone around the Fukushima Daiichi nuclear power plant

Yukihisa Sanada, Atsuya Kondo, Takeshi Sugita, Yukiyasu Nishizawa, Youichi Yuuki, Kazutaka Ikeda, Yasunori Shoji and Tatsuo Torii

17. Published 25 February 2015
Airborne electromagnetic modelling options and their consequences in target definition

Alan Yusen Ley-Cooper, Andrea Viezzoli, Julien Guillemoteau, Giulio Vignoli, James Macnae, Leif Cox and Tim Munday

18. Comparison of numerical dispersion in acoustic finite-difference algorithms

Wen-Quan Liang, Yan-Fei Wang and Chang-Chun Yang

19. Published 30 May 2014
Application of high resolution airborne geophysical data in geological modelling of Mohar Cauldron Complex, Bundelkhand Massif, central India: implications for uranium exploration

A. Markandeyulu, A. K. Chaturvedi, B. V. S. N. Raju, P. S. Parihar, Roger Miller and Glenn Gooch

20. Published 28 November 2014
Remote remanence estimation (RRE)

David A. Pratt, K. Blair McKenzie and Tony S. White


      
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Volume 46 (1)

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