A comparison of the use of X-ray and neutron tomographic core scanning techniques for drilling projects: insights from scanning core recovered during the Alpine Fault Deep Fault Drilling Project
Jack N. Williams
CORRESPONDING AUTHOR
Department of Geology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
Joseph J. Bevitt
Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Lucas Heights NSW 2234, Australia
Virginia G. Toy
Department of Geology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
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Luke N. J. Wedmore, Tess Turner, Juliet Biggs, Jack N. Williams, Henry M. Sichingabula, Christine Kabumbu, and Kawawa Banda
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Mapping and compiling the attributes of faults capable of hosting earthquakes are important for the next generation of seismic hazard assessment. We document 18 active faults in the Luangwa Rift, Zambia, in an active fault database. These faults are between 9 and 207 km long offset Quaternary sediments, have scarps up to ~30 m high, and are capable of hosting earthquakes from Mw 5.8 to 8.1. We associate the Molaza Fault with surface ruptures from two unattributed M 6+ 20th century earthquakes.
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Earthquake hazard is often specified using instrumental records. However, this record may not accurately forecast the location and magnitude of future earthquakes as it is short (100s of years) relative to their frequency along geologic faults (1000s of years). Here, we describe an approach to assess this hazard using fault maps and GPS data. By applying this to southern Malawi, we find that its faults may host rare (1 in 10 000 years) M 7 earthquakes that pose a risk to its growing population.
Jack N. Williams, Virginia G. Toy, Cécile Massiot, David D. McNamara, Steven A. F. Smith, and Steven Mills
Solid Earth, 9, 469–489, https://doi.org/10.5194/se-9-469-2018, https://doi.org/10.5194/se-9-469-2018, 2018
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We present new data on the orientation of fractures, their fill, and their density around the Alpine Fault, a plate boundary fault on the South Island of New Zealand. Fractures < 160 m of the fault are filled and show a range of orientations, whilst fractures at greater distances (< 500 m) are open and parallel to the rock's mechanical weakness. We interpret the latter fracture set to reflect near-surface processes, whilst the latter are potentially linked to deep-seated Alpine Fault seismicity.
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Mapping and compiling the attributes of faults capable of hosting earthquakes are important for the next generation of seismic hazard assessment. We document 18 active faults in the Luangwa Rift, Zambia, in an active fault database. These faults are between 9 and 207 km long offset Quaternary sediments, have scarps up to ~30 m high, and are capable of hosting earthquakes from Mw 5.8 to 8.1. We associate the Molaza Fault with surface ruptures from two unattributed M 6+ 20th century earthquakes.
Jack N. Williams, Luke N. J. Wedmore, Åke Fagereng, Maximilian J. Werner, Hassan Mdala, Donna J. Shillington, Christopher A. Scholz, Folarin Kolawole, Lachlan J. M. Wright, Juliet Biggs, Zuze Dulanya, Felix Mphepo, and Patrick Chindandali
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We use geologic and GPS data to constrain the magnitude and frequency of earthquakes that occur along active faults in Malawi. These faults slip in earthquakes as the tectonic plates on either side of the East African Rift in Malawi diverge. Low divergence rates (0.5–1.5 mm yr) and long faults (5–200 km) imply that earthquakes along these faults are rare (once every 1000–10 000 years) but could have high magnitudes (M 7–8). These data can be used to assess seismic risk in Malawi.
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Publication in SE not foreseen
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In March 2011, the Mw ~9 Tohoku-oki earthquake, one of the largest seismic events ever recorded, occurred across a megathrust fault in the west of the Japan trench. This devastating earthquake stressed the need for more detailed studies on the fault zone behavior and the main causes of this event.
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Solid Earth, 12, 187–217, https://doi.org/10.5194/se-12-187-2021, https://doi.org/10.5194/se-12-187-2021, 2021
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Earthquake hazard is often specified using instrumental records. However, this record may not accurately forecast the location and magnitude of future earthquakes as it is short (100s of years) relative to their frequency along geologic faults (1000s of years). Here, we describe an approach to assess this hazard using fault maps and GPS data. By applying this to southern Malawi, we find that its faults may host rare (1 in 10 000 years) M 7 earthquakes that pose a risk to its growing population.
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Processes associated with open pores can change the physical properties of rocks and cause earthquakes. In borehole samples from the Alpine Fault zone, we show that many pores in these rocks were filled by weak materials that can slide easily. The amount of open spaces was thus reduced, and fluids circulating within them built up high pressures. Both weak materials and high pressures within pores reduce the rock strength; thus the state of pores here can trigger the next Alpine Fault earthquake.
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By quantifying trace concentrations of titanium in quartz (a known geologic “thermometer”), we constrain the temperature profile for the deep crust along the Alpine Fault. We show there is a sharp change from fairly uniform temperatures at deep levels to a very steep gradient in temperature in the upper kilometers of the crust.
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Solid Earth, 9, 469–489, https://doi.org/10.5194/se-9-469-2018, https://doi.org/10.5194/se-9-469-2018, 2018
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We present new data on the orientation of fractures, their fill, and their density around the Alpine Fault, a plate boundary fault on the South Island of New Zealand. Fractures < 160 m of the fault are filled and show a range of orientations, whilst fractures at greater distances (< 500 m) are open and parallel to the rock's mechanical weakness. We interpret the latter fracture set to reflect near-surface processes, whilst the latter are potentially linked to deep-seated Alpine Fault seismicity.
Martina Kirilova, Virginia Toy, Jeremy S. Rooney, Carolina Giorgetti, Keith C. Gordon, Cristiano Collettini, and Toru Takeshita
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Graphite crystallinity “irreversibly” increases with temperature and it has been calibrated as a thermometer recording peak temperatures experienced by a rock. To examine the possibility of mechanical modifications of graphite structure and the impacts on graphite thermometry we performed deformation experiments. Raman spectroscopy demonstrates a reduction in crystallinity due to mechanical reworking in the brittle field. This finding clearly compromises the validity of the graphite thermometry.
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Cited articles
ASTM: (American Society for Testing, Materials), E803-91, Standard Test Method for Determining the L/D Ratio of Neutron Radiography Beams, 2013.
Berryman, K. R., Cochran, U. A., Clark, K. J., Biasi, G. P., Langridge, R. M., and Villamor, P.: Major earthquakes occur regularly on an isolated plate boundary fault, Science, 336, 1690–1693, 2012.
Caine, J. S., Evans, J. P., and Forster, C. B.: Fault zone architecture and permeability structure, Geology, 24, 1025–1028, 1996.
Christe, P., Bernasconi, M., Vontobel, P., Turberg, P., and Parriaux, A.: Three-dimensional petrographical investigations on borehole rock samples: A comparison between X-ray computed- and neutron tomography, Acta Geotech., 2, 269–279, https://doi.org/10.1007/s11440-007-0045-9, 2007.
Freifeld, B. M., Kneafsey, T. J., and Rack, F. R.: On-site geological core analysis using a portable X-ray computed tomographic system, Geol. Soc. London, Spec. Publ., 267, 165–178, 2006.
Garbe, U., Randall, T., and Hughes, C.: The new neutron radiography/tomography/imaging station DINGO at OPAL, in Nuclear Instruments and Methods in Physics Research, Sectio En A: Accelerators, Spectrometers, Detectors and Associated Equipment, 651, 42–46, 2011.
Grader, A. S., Balzarini, M., Radaelli, F., Capasso, G., and Pellegrino, A.: Fracture-Matrix Flow: Quantification and Visualization Using X-Ray Computerized Tomography, in: Dynamics of Fluids in Fractured Rock, edited by: Faybishenko, B., Witherspoon, P. A., and Benson, S. M., 157–168, https://doi.org/10.1029/GM122p0157, 2000.
Hassanein, R., Lehmann, E., and Vontobel, P.: Methods of scattering corrections for quantitative neutron radiography, in: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 542, 353–360, 2005.
Hassanein, R., de Beer, F., Kardjilov, N., and Lehmann, E.: Scattering correction algorithm for neutron radiography and tomography tested at facilities with different beam characteristics, Phys. B Condens. Matter, 385–386, 1194–1196, https://doi.org/10.1016/j.physb.2006.05.406, 2006.
Keren, T. T. and Kirkpatrick, J. D.: The damage is done: Low fault friction recorded in the damage zone of the shallow Japan Trench décollement, J. Geophys. Res. Sol. Ea., 121, 3804–3824, https://doi.org/10.1002/2015JB012311, 2016.
Ketcham, R. A. and Carlson, W. D.: Acquisition, optimization and interpretation of X-ray computed tomographic imagery: applications to the geosciences, Comput. Geosci., 27, 381–400, available at: http://ac.els-cdn.com/S0098300400001163/1-s2.0-S0098300400001163-main.pdf?_tid=47f3eb96-5bd4-11e3-86fc-00000aab0f6b&acdnat=1386045485_e323788eaa9cc76ba255f3fba7abec66, 2001.
Kyle, J. R. and Ketcham, R. A.: Application of high resolution X-ray computed tomography to mineral deposit origin, evaluation, and processing, Ore Geol. Rev., 65, 821–839, https://doi.org/10.1016/j.oregeorev.2014.09.034, 2015.
Masschaele, B., Dierick, M., Van Loo, D., Boone, M. N., Brabant, L., Pauwels, E., Cnudde, V., and Van Hoorebeke, L.: HECTOR: A 240kV micro-CT setup optimized for research, J. Phys. Conf. Ser., 463, 12012, https://doi.org/10.1088/1742-6596/463/1/012012, 2013.
Norris, R. J. and Cooper, A. F.: Late Quaternary slip rates and slip partitioning on the Alpine Fault, New Zealand, J. Struct. Geol., 23, 507–520, 2001.
Rothwell, R. G. and Rack, F. R.: New techniques in sediment core analysis: an introduction, Geol. Soc. London, Spec. Publ., 267, 1–29, 2006.
Schleicher, A. M., Sutherland, R., Townend, J., Toy, V. G., and van der Pluijm, B. A.: Clay mineral formation and fabric development in the DFDP-1B borehole, central Alpine Fault, New Zealand, New Zeal. J. Geol. Geophys., 58, 13–21, 2015.
Schwarz, D., Vontobel, P., Lehmann, E. H., Meyer, C. A., and Bongartz, G.: Neutron Tomography of Internal Structures of Vertebrate Remains?: a Comparison With X-Ray Computed Tomography, Palaeontol. Electron., 8, 11 pp., 2005.
Sills, D. W.: The fabric of clasts, veins and foliations within the actively creeping zones of the San Andreas Fault at SAFOD: implications for deformation processes, 2013.
Sutherland, R., Eberhart-Phillips, D., Harris, R. A., Stern, T., Bevan, J., Ellis, S., Henrys, D., Cox, S., Norris, R. J., Berryman, K. R., Townend, J., Bannister, S., Pettinga, J., Leitner, B., Wallace, L., Little, T. A., Cooper, A. F., Yetton, M., and Stirling, M.: Do great earthquakes occur on the Alpine fault in central South Island, New Zealand?. A continental plate boundary: tectonics at South Island, New Zealand, edited by: Okaya, D., Stern, T., and Davey, F., American Geophysical Union, Washington D.C., 2007.
Sutherland, R., Toy, V. G., Townend, J., Cox, S. C., Eccles, J. D., Faulkner, D. R., Prior, D. J., Norris, R. J., and Mariani, E.: Drilling reveals fluid control on architecture and rupture of the Alpine fault, New Zealand, Geology, 40, 1143–1146, https://doi.org/10.1130/G33614.1, 2012.
Townend, J., Sutherland, R., and Toy, V.: Deep Fault Drilling Project – Alpine Fault, New Zealand, Sci. Dril., 8, 75–82, https://doi.org/10.2204/iodp.sd.8.12.2009, 2009.
Toy, V. G., Boulton, C. J., Sutherland, R., Townend, J., Norris, R. J., Little, T. A., Prior, D. J., Mariani, E., Faulkner, D., Menzies, C. D., Scott, H., and Carpenter, B. M.: Fault rock lithologies and architecture of the central Alpine fault, New Zealand, revealed by DFDP-1 drilling, Lithosphere, 7, 155–173, https://doi.org/10.1130/L395.1, 2015.
Vontobel, P., Lehmann, E., and Carlson, W. D.: Comparison of X-ray and neutron tomography investigations of geological materials, IEEE T. Nucl. Sci., 52, 338–341, 2005.
Voorn, M., Exner, U., Barnhoorn, A., Baud, P., and Reuschlé, T.: Porosity, permeability and 3D fracture network characterisation of dolomite reservoir rock samples, J. Pet. Sci. Eng., 127, 270–285, https://doi.org/10.1016/j.petrol.2014.12.019, 2015.
Wennberg, O. P., Rennan, L., and Basquet, R.: Computed tomography scan imaging of natural open fractures in a porous rock; geometry and fluid flow, Geophys. Prospect., 57, 239–249, 2009.
Williams, J. N., Toy, V. G., Massiot, C., McNamara, D. D., and Wang, T.: Damaged beyond repair? Characterising the damage zone of a fault late in its interseismic cycle, the Alpine Fault, New Zealand, J. Struct. Geol., 90, 76–94, https://doi.org/10.1016/j.jsg.2016.07.006, 2016.
Withjack, E. M., Devier, C., and Michael, G.: The Role of X-Ray Computed Tomography in Core Analysis, Soc. Pet. Eng., SPE Western Regional/AAPG Pacific Section Joint Meeting, 19–24 May, Long Beach, California, https://doi.org/10.2118/83467-MS, 2003.
Short summary
We compare images of drillcore from the Alpine Fault in New Zealand that were collected using X-ray computed tomography (CT) and neutron tomography (NT). Both techniques provide 3-D images of the core's internal structure, which would not be possible through visual analysis alone. We find that CT scans are more beneficial, as they can image a wider range of rock types, and this scanning technique is more practical. Nevertheless, NT provides complementary scans over limited intervals of core.
We compare images of drillcore from the Alpine Fault in New Zealand that were collected using...