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Volume 68 Number 1
  • E-ISSN: 1365-2478
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Abstract

ABSTRACT

Wireline logs and vertical seismic profile data were acquired in two boreholes intersecting the main mineralized zone at the Cu–Au New Afton porphyry deposit, Canada, with the objectives of imaging lithological contacts, fault zones that may have acted as conduits that channelled the mineralization, and alteration zones. Log data provide physical rock properties for the main lithologies and alteration zones. Calliper logs reveal many faults and caved‐in zones generally indicating rocks with low integrity at the borehole wall. The preponderance of these zones, as indicated by the logs, suggests that their response may dominate the seismic‐reflection wavefield. Outside fault zones, compressional and shear‐wave velocities exhibit significant variability due to porosity, the heterogeneity of volcanic fragmental rocks and alteration. Distributed acoustic sensing was used to acquire vertical seismic profiling data in the two boreholes surveyed with wireline logs. Straight and helically wound fibre‐optic cables housed standard fibres and a fibre engineered to increase the intensity of backscattering at the distributed acoustic sensing interrogator. Standard and engineered optical fibres placed in the two boreholes were daisy‐chained together to form two 5‐km‐long continuous fibres that were interrogated at once with two interrogators. A new generation of interrogator connected to the engineered fibres provided field data with lower noise level and higher signal‐to‐noise ratio. These data with higher signal‐to‐noise ratio from straight fibre‐optic cable were processed and used for depth imaging. Depth images benefitted from new migration weights that account for the directional sensitivity of the straight fibre‐optic cable and limit the extent of migration artefacts. Migration results show several reflectors with shallow dips to the northwest, some explained by faults intersecting the surveyed boreholes. The main sub‐vertical lithological and alteration contacts at New Afton generated downgoing reflections that were not considered in the migration.

© 2020 European Association of Geoscientists & Engineers © 2019 The Authors. Geophysical Prospecting published by John Wiley & Sons Ltd on behalf of European Association of Geoscientists & Engineers.
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2019-07-09
2024-04-19

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References

  1. BellefleurG., SchetselaarE., WadeD. and WhiteD.2018. VSP using distributed acoustic sensing with scatter‐enhanced fibre‐optic cable at the Cu–Au New Afton porphyry deposits, Canada. 2nd EAGE Conference on Geophysics for Mineral Exploration and Mining, Porto, Portugal. Extended Abstract Tu 2MIN P05.
  2. BergenD., KrutzlmannH. and RennieD.W.2015. New Gold Inc. – New Afton Project, Project #2400 Technical Report NI 43‐101, 23 March 2015, 256 p.
  3. ChanJ. and SchmittD.R.2015. Initial seismic observations from a deep borehole drilled into the Canadian Shield in northeast Alberta. International Journal of Earth Sciences (Geologische Rundschau)104, 1549–1562.
     [Google Scholar]
  4. ChengC.H. and ToksözM.N.1982. Generation, propagation and analysis of tube waves in borehole. 23rd Society of Petrophysicists and Well‐log Analysts Annual Logging Symposium, Corpus Christi, TX.
  5. ConstantinouA., SchmittD.R., KofmanR.S., KellettR., EcclesJ., LawtonD.et al. and the DFDP Whataroa Science Team . 2016. Comparison of fibre optic sensor and borehole seismometer VSP surveys in a scientific borehole – DFDP‐2, Alpine Fault, New Zealand. SEG Dallas 2016 Annual Meeting.
  6. CorreaJ., EgorovA., TertyshnikovK., BonaA., PevznerR., DeanT.et al. 2017. Analysis of signal to noise and directivity characteristics of DAS VSP at near and far offsets – a CO2CRC Otway Project data example. The Leading Edge36, 994a1–994a7.
     [Google Scholar]
  7. CosmaC., BaluL. and EnescuN.2010. 3D VSP migration by image point transform. Geophysics75, S121–S130.
     [Google Scholar]
  8. DaleyT.M., MillerD.E., DoddsK., CookP. and FreifeldB.M.2016. Field testing of modular borehole monitoring with simultaneous distributed acoustic sensing and geophone vertical seismic profiles at Citronelle, Alabama. Geophysical Prospecting64, 1318–1334.
     [Google Scholar]
  9. DaleyT.M., WhiteD., MillerD.E., RobertsonM., FreifeldB.M., HerkenhoffF.et al. 2014. Simultaneous acquisition of distributed acoustic sensing vsp with multi‐mode and single‐mode fiber optic cables and 3‐component geophones at the Aquistore CO2 storage site. SEG Denver 2014 Annual Meeting.
  10. DeanT., CunyT., ConstantinouA., DickensonP. and HamoucheE.2018. Depth calibration of fibre‐optic distributed vibration sensing measurements. First Break36, 29–34.
     [Google Scholar]
  11. FarhadiroushanM., ParkerT.R. and ShatalinS.2009. Method and Apparatus for Optical Sensing. Patent WO2010136810A2.
  12. FreifeldB.M., PevznerR., DouS., CorreaJ., DaleyT.M., RobertsonM.et al. 2016. The CO2CRC Otway Project deployment of an Areal Distributed Acoustic Sensing Network Coupled with Permanent Rotary Sources. 78th EAGE Conference and Exhibition, Vienna, Austria. Extended Abstract Tu LHR2 06.
  13. Gal'perinE.I.1974. Vertical Seismic Profiling. Special publication No. 12. Society of Exploration Geophysicist, Tulsa, OK.
     [Google Scholar]
  14. GötzJ., LüthS., HenningesJ. and ReinschT.2018. Vertical seismic profiling using daisy‐chained deployment of fibre‐optic cables in four wells simultaneously – case study at the Ketzin carbon dioxide storage site. Geophysical Prospecting66, 1201–1214.
     [Google Scholar]
  15. HardageB.A.2000. Vertical Seismic Profiling Principles. Handbook of Geophysical Exploration, Seismic Exploration. Vol. 14. Pergamon, New York.
     [Google Scholar]
  16. HarrisK., WhiteD., MelansonD., SamsonC. and DaleyT.2016. Feasibility of time‐lapse VSP monitoring at the Aquistore CO2 storage site using a distributed acoustic sensing system. International Journal of Greenhouse Gas Control50, 248–260.
     [Google Scholar]
  17. HartogA.H.2018. An Introduction to Distributed Optical Fibre Sensing. CRC Press.
     [Google Scholar]
  18. HornmanJ.C.2017. Field trial of seismic recording using distributed acoustic sensing with broadside sensitive fibre‐optic cable. Geophysical Prospecting65, 35–46.
     [Google Scholar]
  19. HuangJ.W. and BellefleurG.2012. Joint transmission and reflection traveltime tomography using the fast sweeping methods and the adjoint‐state technique. Geophysical Journal International188, 570–582.
     [Google Scholar]
  20. HumphriesM., VidalJ.A.M. and de DiosJ.C.2015. VSP monitoring for CO2 migration tracking in fractured rock massifs. 77th EAGE Conference & Exhibition, Madrid, Spain, Extended Abstract Tu N112‐02.
  21. KennettB.L.N.1974. Reflections, rays, and reverberations. Bulletin of the Seismological Society of America64, 1685–1696.
     [Google Scholar]
  22. KuvshinovB.N.2016. Interaction of helically wound fibre‐optic cables with plane seismic waves. Geophysical Prospecting64, 671–688.
     [Google Scholar]
  23. LiT. and EatonD.W.2005. Delineating the Tuwu porphyry copper deposit at Xinjiang, China, with seismic‐reflection profiling. Geophysics70, B53–B60.
     [Google Scholar]
  24. LipskeJ. and WadeD.2014. Geological model of the New Afton Copper and Gold Deposit, British Columbia, internal report to New Gold Inc., 53 p.
  25. LouM., ChengD. and DohertyF.2009. Suppressing VSP migration artifacts and noise by selected‐aperture migration and damped least‐square smoothing. SEG Houston 2009 Annual Meeting.
  26. MadsenK.N., TondellR. and KvamO.2016. Data‐driven depth calibration for distributed acoustic sensing. The Leading Edge35, 610–614.
     [Google Scholar]
  27. MateevaA., LopezJ., PottersH., MestayerJ., CoxB., KiyashchenkoD.et al. 2014. Distributed acoustic sensing for reservoir monitoring with vertical seismic profiling. Geophysical Prospecting62, 679–692.
     [Google Scholar]
  28. MillerD. and OristaglioM.1987. A new slant on seismic imaging. Migration and integral geometry. Geophysics52, 943–964.
     [Google Scholar]
  29. MuellerC., BellefleurG., AdamE., PerronG., MahM. and SnyderD.2012. Performance of low‐fold scalar migration for downhole seismic imaging of massive sulfide ore deposits at Norman West, Sudbury, Canada. Geophysics77, WC3–WC13.
     [Google Scholar]
  30. ParkerT., ShatalinS. and FarhadiroushanM.2014. Distributed acoustic sensing – a new tool for seismic applications. First Break32, 61–69.
     [Google Scholar]
  31. RawlinsonN., HauserJ. and SambridgeM.2008. Seismic ray tracing and wavefront tracking in laterally heterogeneous media. Advances in Geophysics49, 203–273.
     [Google Scholar]
  32. RiedelM., CosmaC., EnescuN., KoivistoE., KomminahoK., VaittinenK.et al. 2018. Underground vertical seismic profiling with conventional and fiber‐optic systems for exploration in the Kylylahti polymetallic mine, eastern Finland. Minerals8, 538.
     [Google Scholar]
  33. RoyB. and ClowesR.M.2000. Seismic and potential‐field imaging of the Guichon Creek batholith, British Columbia, Canada, to delineate structures hosting porphyry copper deposits. Geophysics65, 1418–1434.
     [Google Scholar]
  34. SchijnsH., SchmittD.R., HeikkinenP.J. and KukkonenI.T.2012. Seismic anisotropy in the crystalline upper crust: observations and modeling from the Outokumpu scientific borehole, Finland. Geophysical Journal International189, 541–553.
     [Google Scholar]
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Vertical seismic profiling using distributed acoustic sensing with scatter‐enhanced fibre‐optic cable at the Cu–Au New Afton porphyry deposit, British Columbia, Canada
Geophysical Prospecting 68, 313 (2020); https://doi.org/10.1111/1365-2478.12828
/content/journals/10.1111/1365-2478.12828
/content/journals/10.1111/1365-2478.12828
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  • Article Type: Research Article
Keyword(s): Distributed acoustic sensing; Helically wound fibre‐optic cable; Porphyry deposit; Vertical seismic profiling

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