Exploration Geophysics (EXPLOR GEOPHYS)

Publisher: CSIRO Publishing

Journal description

Exploration Geophysics publishes excellent research in geophysics, reviews, technical papers and significant case histories in minerals, petroleum, mining and environmental geophysics, and is an official publication of the Australian Society of Exploration Geophysicists (ASEG). Authors and readers are professional earth scientists specialising in the practical application of the principles of physics and mathematics to solve problems in a broad range of geological situations. They are variously in industry, government and academic research institutions. All papers are peer reviewed. Four issues are published each year in both print and online versions and some issues include special sections of particular topics, or collections of papers from the regular ASEG Conferences. We also publish a joint issue as Mulli-Tamsa with the Korean Society of Exploration Geophysicists and as Butsuri-Tansa with the Society of Exploration Geophysicists of Japan; this issue goes to all three societies.

Current impact factor: 0.51

Impact Factor Rankings

2016 Impact Factor Available summer 2017
2014 / 2015 Impact Factor 0.508
2013 Impact Factor 0.554
2012 Impact Factor 0.667
2011 Impact Factor 0.634
2010 Impact Factor 0.619
2009 Impact Factor 0.404

Impact factor over time

Impact factor

Additional details

5-year impact 0.88
Cited half-life >10.0
Immediacy index 0.50
Eigenfactor 0.00
Article influence 0.34
Website Exploration Geophysics website
ISSN 0812-3985
OCLC 180103031
Material type Periodical, Internet resource
Document type Internet Resource, Computer File, Journal / Magazine / Newspaper

Publisher details

CSIRO Publishing

  • Pre-print
    • Author can archive a pre-print version
  • Post-print
    • Author can archive a post-print version
  • Conditions
    • On author's personal repository or institutional repository
    • Must link to publisher version
    • Published source must be acknowledged
    • Publisher's version/PDF cannot be used
  • Classification

Publications in this journal

  • No preview · Article · Feb 2016 · Exploration Geophysics

  • No preview · Article · Jan 2016 · Exploration Geophysics

  • No preview · Article · Jan 2016 · Exploration Geophysics

  • No preview · Article · Jan 2016 · Exploration Geophysics

  • No preview · Article · Jan 2016 · Exploration Geophysics

  • No preview · Article · Jan 2016 · Exploration Geophysics
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    ABSTRACT: In wave-equation-based migration, the imaging condition is an important factor that impacts migration accuracy and efficiency. Among the commonly used imaging conditions, the excitation amplitude imaging condition has high resolution, accuracy and low storage and input/output burden when compared with others. However, the excitation amplitude extracted by this imaging condition in its current form will produce a distorted migration image for certain scenarios. In this paper, a modified excitation amplitude imaging condition is proposed that addresses the above problem and produces migrated images free from distortion for complicated geologic models. In this paper, we propose a method to effectively use the modified shortest path method (MSPM) 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. This process can, to some extent, improve the distorted migration image produced by the traditional excitation amplitude imaging condition. Some numerical tests with synthetic data of Sigsbee2a and Marmousi-II models show that the improvement is feasible and effective in complex-structure media.
    No preview · Article · Dec 2015 · Exploration Geophysics
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    ABSTRACT: One-way wave equation migration is computationally efficient compared with reverse time migration, and it provides a better subsurface image than ray-based migration algorithms when imaging complex structures. Among many one-way wave-based migration algorithms, we adopted the generalised screen propagator (GSP) to build the migration algorithm. When the wavefield propagates through the large velocity variation in lateral or steeply dipping structures, GSP increases the accuracy of the wavefield in wide angle by adopting higher-order terms induced from expansion of the vertical slowness in Taylor series with each perturbation term. To apply the migration algorithm to a more realistic geological structure, we considered tilted transversely isotropic (TTI) media. The new GSP, which contains the tilting angle as a symmetric axis of the anisotropic media, was derived by modifying the GSP designed for vertical transversely isotropic (VTI) media. To verify the developed TTI-GSP, we analysed the accuracy of wave propagation, especially for the new perturbation parameters and the tilting angle; the results clearly showed that the perturbation term of the tilting angle in TTI media has considerable effects on proper propagation. In addition, through numerical tests, we demonstrated that the developed TTI-GS migration algorithm could successfully image a steeply dipping salt flank with high velocity variation around anisotropic layers.
    No preview · Article · Dec 2015 · Exploration Geophysics
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    ABSTRACT: Leachate from livestock mortality burial is harmful to the soil and groundwater environment and adequate assessment approaches are necessary to manage burial sites. Among the methods used to detect leachate, geophysical surveys, including electrical resistivity and electromagnetic (EM) techniques, are used in many engineering approaches to environmental problems, such as identifying contaminant plumes and evaluating hydrogeological conditions. Electrical resistivity, with a small-loop EM survey, was used in this study as a reconnaissance technique to identify the burial shape and distribution of leachate from livestock mortality burial in five small separate zones. We conducted a multi-frequency small-loop EM survey using lattice nets and acquired apparent conductivity values along several parallel and perpendicular lines over a burial site. We also compared geophysical results to the geochemical analysis of samples from both a leachate collection well and a downstream observation well within the study area. Depth slices of apparent conductivities at each frequency (obtained from the small-loop EM survey data) clearly identified the subsurface structure of the burial shape and the extent of leachate transport. Low-resistivity zones, identified from two-dimensional (2D) electrical resistivity imaging results, were matched to the five burial zones (within a depth of 5m), as well as high electrical conductivity of the leachate obtained from leachate collection wells, and depth slices of the apparent conductivity distribution obtained from the small-loop EM survey. A three-dimensional (3D) inversion of resistivity data provided a detailed 3D structure of the overall burial site and leachate pathways. Moreover, these zones were widely spread over the burial site, indicating that leachate potentially extended through damaged regions of the composite liner to a depth of 10m along the downstream groundwater flow. Both the small-loop EM method and the electrical resistivity method were considered suitable for identifying the shape of the livestock mortality burial and the extent of leachate.
    No preview · Article · Dec 2015 · Exploration Geophysics
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    ABSTRACT: The relationship between the self-potential (SP) produced by a polarised sphere and its depth was studied in a laboratory experiment. This was carried out by using a sphere made up of two hemispheres of different materials: one copper and the other zinc. Self-potentials were measured by placing the sphere at a given depth in a rectangular glass tank filled with water. The surface of the water was covered by a sheet with 684 brass electrodes. A sensitive, high impedance digital voltmeter was used to measure potentials from each electrode to a 'base'. We have measured the SP response of the metallic body and our work shows that SP signals of several millivolts are generated due to the sphere placed within water. The gridded SP data show a clear anomaly over the sphere at shallow depths, and as the depth of the sphere increases, the measured SP signal due to the sphere decreases. An analytical formula is given to determine the maximum depth of the sphere at which the presence of the anomaly can be detected. Responses from other geometries are examined as well.
    No preview · Article · Dec 2015 · Exploration Geophysics
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    ABSTRACT: Population growth along the coast of eastern Australia has increased demand for new and upgraded transport infrastructure within intervening coastal floodplains and steeper hinterland areas. This has created additional challenges for road foundation design. The floodplain areas in this region are underlain by considerable thicknesses of recently deposited alluvial and clayey marine sediments. If characterisation of these deposits is inadequate they can increase road construction costs and affect long-term road stability and serviceability. Case studies from a major coastal highway upgrade demonstrate how combining surface wave seismic and electrical geophysical imaging with conventional geotechnical testing enhances characterisation of these very soft and soft soils. The geophysical results also provide initial foundation design parameters such as void ratio and pre-consolidation pressure. A further significant risk issue for roads is potential embankment instability. This can occur during new road construction or when upgrades of existing embankments are required. Assessing the causes of instability of existing steeper embankments with drilling and probing is often difficult and costly due to access and safety problems. In these situations combinations of electrical, ground penetrating radar and P-wave seismic imaging technologies can rapidly provide information on the likely conditions below both the roadway and embankment. Case studies show the application of these technologies on two unstable road embankments. It is concluded that the application of both geophysical imaging and geotechnical testing is a cost-effective enhancement for site characterisation of soft soils and for risk assessment of potentially unstable embankments. This approach overcomes many of the current limitations of conventional methods of site investigation that provide point location data only. The incorporation of geophysics into a well crafted site investigation allows concentration on fewer but higher quality soil probings and geotechnical boreholes.
    No preview · Article · Dec 2015 · Exploration Geophysics
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    ABSTRACT: Rapid interpretation of large airborne transient electromagnetic (ATEM) datasets is highly desirable for timely decision-making in exploration. Full solution 3D inversion of entire airborne electromagnetic (AEM) surveys is often still not feasible on current day PCs. Therefore, two algorithms to perform rapid approximate 3D interpretation of AEM have been developed. The loss of rigour may be of little consequence if the objective of the AEM survey is regional reconnaissance. Data coverage is often quasi-2D rather than truly 3D in such cases, belying the need for `exact' 3D inversion. Incorporation of geological constraints reduces the non-uniqueness of 3D AEM inversion. Integrated interpretation can be achieved most readily when inversion is applied to a geological model, attributed with lithology as well as conductivity. Geological models also offer several practical advantages over pure property models during inversion. In particular, they permit adjustment of geological boundaries. In addition, optimal conductivities can be determined for homogeneous units. Both algorithms described here can operate on geological models; however, they can also perform `unconstrained' inversion if the geological context is unknown. VPem1D performs 1D inversion at each ATEM data location above a 3D model. Interpretation of cover thickness is a natural application; this is illustrated via application to Spectrem data from central Australia. VPem3D performs 3D inversion on time-integrated (resistive limit) data. Conversion to resistive limits delivers a massive increase in speed since the TEM inverse problem reduces to a quasi-magnetic problem. The time evolution of the decay is lost during the conversion, but the information can be largely recovered by constructing a starting model from conductivity depth images (CDIs) or 1D inversions combined with geological constraints if available. The efficacy of the approach is demonstrated on Spectrem data from Brazil. Both separately and in combination, these programs provide new options to exploration and mining companies for rapid interpretation of ATEM surveys.
    No preview · Article · Oct 2015 · Exploration Geophysics
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    ABSTRACT: Forward modelling of airborne time-domain electromagnetic (ATDEM) responses is frequently used to compare systems and design surveys for optimum detection of expected mineral exploration targets. It is a challenging exercise to display and analyse the forward modelled responses due to the large amount of data generated for three dimensional models as well as the system dependent nature of the data. I propose simplifying the display of ATDEM responses through using the dimensionless quantity of signal-to-noise ratios (signal:noise) instead of respective system units. I also introduce the concept of a three-dimensional signal:noise nomo-volume as an efficient tool to visually present and analyse large amounts of data. The signal:noise nomo-volume is a logical extension of the two-dimensional conductance nomogram. 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. Responses are calculated over a complete survey grid and therefore include effects of system and target geometries. The user can interactively select signal:noise cut-off values on the nomo-volume and is able to perform visual comparisons between various system and target responses. The process is easy to apply and geophysicists with access to forward modelling airborne electromagnetic (AEM) and three-dimensional imaging software already possess the tools required to produce and analyse signal:noise nomo-volumes.
    No preview · Article · Sep 2015 · Exploration Geophysics