b'FeatureEstimating Nth-order vertical gradientsNth-order horizontal gradient otherwise there will not be aReferencesmeaningful response in the Nth-order vertical gradient.Abramowitz, M. and I. A. Stegun. 1972. Handbook of Mathematical Functions, The method will also convert measured horizontal gradientsDover Publications.from airborne magnetics to vertical gradients (or vice versa)Beyer, W., H. 1984. CRC Standard Mathematical Tables, 27th ed., CRC Press, without loss or distortion of any frequency content. 447-448.We choose a set of derivative operators that are adequate forBracewell, R. 1965. The Fourier transform and its applications. McGraw-Hill. the task. Operators that provide greater sensitivity to noise viaFitzgerald, D. J. 2023. A sliding doors moment. Preview: 224, 32-35.curve fitting, e.g. Savitzky-Golay, may yield better results. OConnell, M. D. 2001. A heuristic method of removing micropulsations from The new method is also suitable for gravimetric data sets. airborne magnetic data. The Leading Edge: 20(11), 1242-1246.Press, W. H., B. P. Flannery, S. A. Teukolsky and W. T. Vetterling. 1992. Numerical Recipes in FORTRAN: The Art of Scientific Computing, 2nd ed. Cambridge University Press.Savitzky, A. and M.J.E. Golay. 1964. Smoothing and differentiation of data by simplified least squares procedures. Analytical Chemistry: 36(8), 1627-1639.Thurston, J. B. and B. Fornberg. 2024. Analytic continuation: A tool for aeromagnetic data interpretation. The Leading Edge: 43(4), 228-234. HENDERSON RE-BYTE: The strengths of CMEsIn a previous Henderson Byte (Preview:220, 35), Coronal MassCiaran Beggan and colleagues at the British Geological Ejections (CMEs) were described and, in particular, as theirSurvey have digitised paper recordings of the magnetic effect on human health. On 10 May 2024, a CME emanatingfield throughout the Carrington event time from two from a massive sunspot 17 times the width of the Earth, causedobservatories in London (New Scientist, 30 March 2024). The an extreme geomagnetic effect, the strongest in 20yearsrate of change of the magnetic intensity computed from the with the strongest possible rating of G5. Spectacular aurorasmagnetograms was of the order of 500 nT/min which is far have been observed even to unusually low latitudes butmore than 350 nT/min which is normally considered a 1-in-fortunately disruption to power grids, satellites or GPS timing100-year event. Incidentally, the magnetic trace went off services, as occurred last in October 2003, have not beenthe chart at the time. Thus, the Carrington event was even reported. Any effect on human health is yet to be discovered. more extreme than originally thought. A similar event today In terms of strength, a comparison is often made to thewould certainly knock out communication systems, power strongest CME said to have reached Earth so far, called thegrids and satellites, thus causing havoc. Carrington event of September 1859. Until now, numericalRoger Hendersoninformation on the event to compare it to recent events wasE rogerhenderson574@gmail.comunavailable but it has just now been verified that it is still the most intense CME so far.The ASEG in social mediaFollow all our socialssocial sow+shl for the latest updates![adjective]Relating to society or its organisation[noun]Social media sites, applications or accounts E C D Q M kVenue and dates locked in forASEGs inaugural DISCOVER conference!1518 October 2024Wrest Point Hotel, HobartJUNE 2024PREVIEW 47'