b'Seismic window Seismic windowto the pre-occupation of average (andAnyway, as you mentioned Terry, a new I really mean average) interpretationmind-set is definitely needed but not just geophysicists simply wanting railwayin the interpretation area - it goes back to lines that they can easily map so that thefully utilising all the data acquired and, in majority of informative (and often veryAlistair Browns words (which was actually relevant) information is processed (orapplied to processed 3D data!) LET THE washed out of the data)? Thus, I sincerelyDATA SPEAK.trust the mineral guys (or should thatI sincerely hope that your and Micks be persons?) wont take a leaf out ofarticles on hard rock seismic will generate the average oil/gas guys playbook andmore discussion and perhaps change the instead apply some critical thinking to themind-set of at least some ASEG Members!issues at hand.Michael MicenkoSome issues that come to mind: Thanks for writing about the topic.Associate Editor for Petroleum The seismic wave is more than a simpleCheersmick@freogeos.com.au reflected waveThere are refractions, surface waves,Johneven multiples, etc - the pre-occupationJohn then followed up with a second Minerals industry fan mail with removing these in processingletter after hed done some research. One of my regular correspondents wrote(or acquisition) as opposed to usingHe found there had been a great deal to me a few months ago (actually hethem to invert the whole data set toof work done in the last ten years and wrote to my colleague Terry Harvey -a model of the subsurface, means thatsuggested a workshop on the topicAssociate Editor for Minerals geophysicswe are not using all the data availableMy concern is about the younger crop of and copied me) regarding our recentto us. interpreters who, partly due to the great articles on seismic for mineralsMany oil/gas interpreters these daysrotation, dont have sufficient guidance to exploration. completely ignore the shallow sectionunderstand what good seismic data really and simply map the railway linesis. Anyway, that possibly a discussion for John Hughes has some ideas for theproduced for them by compliantanother day!mineral exploration geologists andprocessing geophysicists. This is even geophysicists to consider before theythough the signals that they areHaving Googled the topic since first hurl themselves into the seismic domain.mapping have travelled through (andbringing it up, I note that there was quite a Our exchange is reproduced below: generally been distorted by) the variablelot of activity in the early part of the (20)10s geology between the surface and the(quite a few papers dated 2012) and that target horizon. Recently, in a review ofCurtins hard rock seismic involvement was an area, I noted that a well had beenas part of the DETCRC, which ran from 2010 drilled into a very significant sink-holebut wound up in 2018. The DETCRC (Deep (the rig nearly sunk into it and causedExploration Technologies CRC) website is a doubling of the drilling budget!).still running and I found a summary of their This location was on a seismic lineobjectives and proposed outcomes.that actually showed a problem in the shallow section at the well location andI note their focus was on 3D reflection had it been properly investigated, wouldseismic which, to my mind, was probably have highlighted the risk. a mistake (trying to run before they could Im of the view that there is actuallywalk). There was probably a lot of other huge (and I mean huge!) potentialwork using refracted waves and surface John Hughesin reprocessing already acquiredwaves as well as reflected waves on 2D John R Hughes Geophysical Pty Ltdonshore seismic data (especially moreseismic that should have been carried jrhgeo@ozemail.com.au recently recorded nodal data) but thisout before pushing the concept of 3D Hi Terry (and Mick) time using the very significant amountreflection seismic for hard rock exploration of additional data conventional(note the word exploration, and not Your article on hard rock seismic in theseismic processing has thrown awaydevelopment/mining which, to me, would latest Preview, along with Micks forays(using routines such as first breakmake more sense).into the topic in Issues 210 and 213 willsuppression and FK filtering). This hopefully generate some interest in whatwould involve integrating other typesI suspect the cost of 3D reflection seismic could very well be a much more valuableof waves in the data such as refractedwas too much for most mineral explorers to tool in mineral exploration than hithertowaves and surface waves into theseriously consider.accepted (or realised!). solution. Terry, do you have any mineral industry The above point may give the mineralscomment on what DETCRC project 3.1 Unfortunately, especially here in Oz, theguys a stepping stone to evaluatingactually achieved?oil/gas industry appears to have lost itsthe usefulness of seismic data without way in its appreciation of what seismicthe quantum leap (and budget!) ofId be a bit concerned about making a data can achieve. Perhaps that is dueacquiring a new seismic data set. workshop or special session (if it were to 35 PREVIEW APRIL 2022'