b'David Annetts best of Exploration GeophysicsFeatureDavid Annetts best of Exploration Geophysicsthree of the papers five authors remain active and equally pleasing that the paper was a product of the CRC-AMET program which served to align industry, government and academic institutions towards the solution of a difficult topical problem. Supported by a number of papers (e.g. Macnae, Bishop, and Munday 2001; Worrall et al. 2001) showing practical applications, my choice for best Exploration Geophysics paper was published at a time to take advantage of the unique confluence of theoretical and instrumental developments, computing power, and offering the promise of processing electromagnetic data in a conductivity-depth transformation so that results looked like geology, and encouraging further development of both rapid approximate and slower, more David Annettsrigorous techniques, the algorithm described by Macnae et al. ASEG President 2020 - (1998) made electromagnetic data easily accessible. In my view, David.Annetts@csiro.au their work was timely, impactful and presaged a future in which a data set providing unique insight into the earths structure could be an integral part of an exploration program and that is It is an honour and a pleasure to be able to review 50 years ofwhy it is my choice of best paper in Exploration Geophysics.ASEG technical material in order to choose the best. However, nominating a best paper, even with implicit disclaimersBest paperaround comparisons of work from minerals, petroleum and geo-technical applications from different periods, andMacnae, J., A. King, N. Stolz, A. Osmakoff, and A. Blaha. 1998. Fast assuming the establishment of a useful metric, is a particularlyAEM data processing and inversion. Exploration Geophysics 29, uncomfortable task. 163169.Unashamedly, I drew candidates from my somewhat narrow field of time-domain electromagnetic prospecting in the hopeReferencesof easing my task. Yet even with self-imposed restrictions, the task is not so simple because the field requires cooperation ofBuselli, G., and B. ONeill. 1977. SIROTEM: A New Portable hardware and software components in order to successfullyInstrument for Multichannel Transient Electromagnetic interpret the data using physics-based models to provideMeasurements. Exploration Geophysics 8: 8287.quantitative predictions. This article, therefore, offers a numberDuncan, A., G. Roberts, G. Buselli, J. Pik, D. Williamson, P. Roocke, of honourable mentions before nominating my choice of bestR. Thorn, and A. Anderson. 1992. SALTMAPairborne EM for paper from 50 years of Exploration Geophysics. the environment. Exploration Geophysics 23: 123126.A hardware-centric approach to a choice of best paper mightElliott, P. 1998. The Principles and Practice of FLAIRTEM. start with the introduction of SIROTEM by Buselli and ONeillExploration Geophysics 29: 5859.(1977). Summarising work that commenced only two years afterLane, R., C. Plunkett, A. Price, A. Green, and H. Yiding. 1998. the formation of the ASEG, they describe SIROTEMs design andStreamed data - A source of insight and improvement for provide field examples of the instruments use. A continuationtime domain airborne EM. Exploration Geophysics 29: 1623.of this theme might sojurn at Duncan et al. (1992) whoLane, R., A. Green, C. Golding, M. Owers, P. Pik, C. Plunkett, D. described the SALTMAP system which evolved to Tempest AEMSattel, and B. Thorn. 2000. An Example of 3D Conductivity system (Lane et al. 2000) that is currently being flown in orderMapping Using the TEMPEST Airborne Electromagnetic to map electrical conductivity as part of Geoscience AustraliasSystem. Exploration Geophysics 31: 162172.AusAEM program (Ley-Cooper et al, 2018). From left-field,Macnae, J., J. Bishop, and T. Munday. 2001. Simplified electrical Elliotts (1998) introduction of the FLAIRTEM system might be astructure models at AEM scales, Lawlers, Western Australia. courageous, prescient choice with the industry on the cusp ofExploration Geophysics 32: 2935.ubiquitous drone use. McCracken, K. G., J. P. Pik, and R. W. Harris. 1984. Noise in EM Exploration Systems. Exploration Geophysics 15: 169174.Noise determines what can reasonably be interpreted fromWorrall, L., R. Lane, J. Meyers, and A. Whitaker. 2001. Exploring measured data. Thus, work by Lane et al. (1998), who describedthrough cover - the integrated interpretation of high noise sources in the use of streamed data by the Tempestresolution aeromagnetic, airborne electromagnetic and AEM system must also be considered on the same level asground gravity data from the Grants Patch area, Eastern hardware, as must work by McCracken, Pik, and Harris (1984)Gold-fields Province, Archaean Yilgarn Craton Part A: who described noise sources and offered practical proceduresMapping geology using airborne EM. Exploration Geophysics to minimise some noise sources. 32: 190193.Macnae, J., A. King, N. Stolz, A. Osmakoff, and A. Blaha. 1998. Fast In my choice of best Exploration Geophysics paper, I consideredAEM data processing and inversion. Exploration Geophysics timeliness, impact and foresight. It is especially pleasing that29: 163169.OCTOBER 2020 PREVIEW 44'