Authors: Ogasawara, H; Liebenberg, B; Rickenbacher, M; Ziegler, M; van Esterhuizen, H; Onstott, TC; Durrheim, RJ, Manzi, MSD; Mngadi, S; Yabe, Y; Ogasawara, H; Kaneki, S; Cason, E; Vermeuren, J-G; van Heerden, E; Wiersberg, T; Zimmer, M; Kujawa, C; Conze, R; van Aswegen, G; Wechsler, N; Ward, AK; Enslin, S; Tau, S; Bucibo, MS


DOI https://doi.org/10.36487/ACG_rep/1952_28_Ogasawara

Cite As:
Ogasawara, H, Liebenberg, B, Rickenbacher, M, Ziegler, M, van Esterhuizen, H, Onstott, TC, Durrheim, RJ, Manzi, MSD, Mngadi, S, Yabe, Y, Ogasawara, H, Kaneki, S, Cason, E, Vermeuren, J-G, van Heerden, E, Wiersberg, T, Zimmer, M, Kujawa, C, Conze, R, van Aswegen, G, Wechsler, N, Ward, AK, Enslin, S, Tau, S & Bucibo, MS 2019, '2019 status report: Drilling into seismogenic zones of M2.0–M5.5 earthquakes in South African gold mines (DSeis project)', in W Joughin (ed.), Deep Mining 2019: Proceedings of the Ninth International Conference on Deep and High Stress Mining, The Southern African Institute of Mining and Metallurgy, Johannesburg, pp. 375-384, https://doi.org/10.36487/ACG_rep/1952_28_Ogasawara

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Abstract:
In 2014, a M5.5 earthquake ruptured the range of depths between 3.5 km and 7 km near Orkney, South Africa. The main and aftershocks were very well monitored in the nearfield by dense, surface, strong motion meters and a dense underground seismic network in the deep gold mines. The mechanism of this M5.5 earthquake was left-lateral strike-slip faulting, differing from typical mining-induced earthquakes with normal-faulting mechanisms on the mining horizons shallower than 3.5 km depth. To understand why such an unusual event took place, the aftershock zone was probed by full-core NQ drilling during 2017-2018, with a total length of about 1.6 km, followed by in-hole geophysical logging, core logging, core testing, and monitoring in the drilled holes. These holes also presented a rare opportunity to investigate deep life. In addition, seismogenic zones of M2–M3 earthquakes were probed on mine horizons that were also very well monitored by acoustic emission networks. This paper reviews the early results of the project.

References:
Brodsky, E.E., Ma, K.-F., Mori, J., Saffer, D.M. and the participants of the ICDP/SCEC International Workshop (2009). Rapid response fault drilling: past, present, and future. Scientific Drilling, 8, 66–74.
Catuneanu, O. and Biddulph, M.N. (2001). Sequence stratigraphy of the Vaal Reef facies associations in the Witwatersrand foredeep, South Africa. Sedimentary Geology, 141–142, 113–130.
Durrheim, R.J. (2015). Geophysical laboratories in deep gold mines: earthquakes, neutrinos, extremophiles and the origin of the Earth’s magnetic field. The History of Geophysics in Southern Africa. J.H. de Beer (ed.). SUN MeDIA, Stellenbosch, pp. 116–138.
Ellsworth, W., Boettcher, M. and Ogasawara, H. (2017). A Test Case for the Source Inversion Validation: The 2014 ML 5.5 Orkney, South Africa Earthquake. Southern California Earthquake Center 2017 Annual Meeting, FARM, Poster199, 10-13 September 2017
Funato, A. and Ito, T. (2017). A new method of diametrical core deformation analysis for in-situ stress measurements, Int. J. Rock Mech. Min. Sci., 91, 112-118, doi: 10.1016/j.ijrmms.2016.11.002.
Hickman, S., Zoback, M., Ellsworth, W., Boness, N., Malin, P., Roecker, S. and Thurber, C. (2007). Structure and properties of the San Andreas Fault in central California recent results from the SAFOD experiment. Scientific Drilling, Special Issue 1, 29–32.
Hirono, T., Asayama, S., Kaneki, S. and Ito, A. (2016). Preservation of amorphous ultrafine material: A proposed proxy for slip during recent earthquakes on active faults. Scientific Reports, 6, 36536.
Hofmann, G., Scheepers, L. and Ogasawara, H. (2013). Loading conditions of geological faults in deep level tabular mines. Proceedings of the 6th Int. Symp. on In-Situ Rock Stress (RS2013), Sendai, Japan.
Imanishi, K., Ogasawara, H., Yabe, Y., Horiuchi, S., Okubo, M. and Murakami, O. (2017). Source parameters of the 2014 M5.5 Orkney earthquake sequence, South Africa, by using near-field underground seismic arrays in gold mines. Abstracts IASPEI 2017 Kobe, S02-1-03.
Kaneki, S., Yokoyama, Y., Hirono, T., Yabe, Y. and Ogasawara, H. (2018). Mineralogical characteristics of fault rocks recovered from aftershock zone of the M5.5 Orkney earthquake in South Africa (ICDP DSeis project). Abstracts Japan Seismol. Soc. Fall Meeting, S0-06.
Linzer, L., Manzi, M. and ICDP DSeis team (2018). Interpretation of the merged 3D seismic volume covering the seismogenic zone of M5.5 Orkney earthquake, South Africa, Abstract Jpn. Seismol. Soc. Fall Meeting S08-05, Koriyama, 10 October 2018.
Manzunzu, B., Midzi, V., Mangongolo, A. and Essrich, F. (2017). The aftershock sequence of the 5 August 2014 Orkney earthquake (ML 5.5), South Africa. J. Seismol. doi: 10.1007/s10950-017-9667-z.
Midzi, V., Zulu, B., Manzunzu, B., Mulabisana, T., Pule, T., Myendeki, S. and Gubela W. (2015). Macroseismic survey of the ML5.5, 2014 Orkney earthquake, J. Seismol, 19: 741–751. .
Mngadi, S.B., Durrheim, R.J., Manzi, M.S.D., Ogasawara, H., Yabe, Y., Yilmaz, H., Wechsler, N., Van Aswegen, G., Roberts, D., Ward, A.K., Naoi, M., Moriya, H., Ishida, A., SATREPS team and ICDP DSeis team. (2019). Integration of underground mapping, petrology, and high-resolution microseismicity analysis to characterise weak geotechnical zones in deep South African gold mines. International Journal of Rock Mechanics and Mining Sciences. 114, 79–91. .
Moore, D.E. and Lockner, D.A. (2004). Crystallographic controls on the frictional behavior of dry and water-saturated sheet-structure minerals. J. Geophys. Res., 109, B03401,
Moore, D.E. and Michael J.R. (2007). Talc-bearing serpentinite and the creeping section of the San Andreas fault. Nature, 446:16, 795-797. .
Mori, J. and Ellsworth, W. (2013). Active fault and earthquakes. Unravelling the Workings of Planet Earth – Science Plan for 2014-2019, pp. 24-31.
Science_Conference/ICDP_SciencePlan2014_2019.pdf
Mori, J.J., Yasutomi, T. and Ogasawara, H. (2018). Close Observations of the Rupture for the M5.5 Orkney, South Africa Earthquake. Tuesday, 11 December 2018. Abstract AGU Fall Meeting. S21C-0438.
Moyer, P.A., Boettcher, M.S., Ellsworth, W.L., Ogasawara, H., Cichowicz, A., Birch, D. and van Aswegen, G. (2017), Call for Models—A Test Case for the Source Inversion Validation: The 2014 ML 5.5 Orkney, South Africa, Earthquake, Seismol. Res. Lett., 88(4), doi: 10.1785/0220160218
Nakatani, M., Yabe, Y., Philipp, J., Morema, G., Stanchits, S., Dresen, G. and JAGUARS Group (2008). Acoustic emission measurements in a deep gold mine in South Africa—Project overview and some typical waveforms, Seismol. Res. Lett., 79, 311.
Naoi, M., Nakatani, M., Yabe, Y., Kwiatek, G., Igarashi, T. and Plenkers, K. (2011). Twenty thousand aftershocks of a very small (M2) earthquake and their relation to the mainshock rupture and geological structures. Bull. Seis-mol. Soc. Amer. 101, 2399-2407, doi: 10.1785/0120100346.
Naoi, M., Nakatani, M., Horiuchi, S., Yabe, Y., Philipp, J., Kgarume, T., Morema, G., Khambule, S., Masakale, T., Ribeiro, L., Miyakawa, K., Watanabe, A., Otsuki, K., Moriya, H., Murakami, O., Kawakata, H., Yoshimitsu, N., Ward, A., Durrheim, R. and Ogasawara, H. (2014). Frequency–magnitude distribution of -3.7 < Mw < 1 mining-induced earthquakes around a mining front and b value invariance with post-blast time. Pure and Applied Geophysics, 171, 2665–2684. doi 10.1007/s00024-013-0721-7.
Naoi,M.,Nakatani,M.,Otsuki,K.,Yabe,Y.,Kgarume,T.,Murakami,O.,Masakale,T., Ribeiro,L.,Ward,A.,Moriya,H.,Kawakata, H.,Durrheim,R. and Ogasawara,H. (2015a). Steady activity of microfractures on geological faults loaded by mining stress,Tectonophysics,649, 100–114. doi: 10.1016/j.tecto.2015.02.025.
Naoi,M., Nakatani, M., Kgarume, T., Khambule, S., Masakale, T., Ribeiro, L., Philipp, J., Horiuchi, S., Otsuki, K., Miyakawa, K., Watanabe, A., Moriya, H., Murakami, O., Yabe, Y., Kawakata, H., Yoshimitsu, N., Ward, A., Durrheim, R. and Ogasawara, H. (2015b). Quasi-static slip patch growth to 20 m on a geological fault inferred from acoustic emissions in a South African gold mine,Journal of Geophysical Research Solid Earth, 120, 1692–1707.
Naoi, M., Nakatani, M., Igarashi, T., Otsuki, K., Yabe, Y., Kgarume, T., Murakami, O., Masakale, T., Ribeiro, L., Ward, A., Moriya, H., Kawakata, H., Nakao, S., Durrheim, R. and Ogasawara, H. (2015c). Unexpectedly frequent occurrence of very small repeating earthquakes (–5.1 ≤ MW ≤ –3.6) in a South African gold mine: implications for monitoring intraplate faults, Journal of Geophysical Research, 120, 8478–8493.
Ogasawara, H., Kato, H., Hofmann, G. and De Bruin, P. (2012). Trial of the BX conical-ended borehole overcoring stress measurement technique, J. SAIMM, 102, 749-754.
Ogasawara, H., Nakatani, M., Durrheim, R.J., Naoi, M., Yabe, Y., Moriya, H., Hofmann, G.F., Stander, C., Roberts, D.P., De Bruin, P., Oelofse, J., Kato, H., Cichowicz, A., Birch, D., Ngobeni, D., Milev, A., Kgarume, T., Satoh, T., Horiuchi, S., Kawakata, H., Murakami, O., Yoshimitsu, N., Ward, A.K., Wienand, J., Lenegan, P., Yilmaz, H., Mngadi, S., Piper, P.S., Clements, T.N., Nakao, S., Okubo, M., Ishii, H. and Visser, A.V. (2014a). Observational studies of the rock mass response to mining in highly-stressed gold mines in South Africa. Proceedings of the Seventh International Congress on Deep and High Stress Mining, Hudyma, M. and Potvin, Y. (eds), Australian Centre for Geomechanics, Perth. pp. 123–137.
Ogasawara, H., Kato, H., Hofmann, G., Roberts, D., Piper, P., Clements, T., Ward, A.K., Yabe Y., Yilmaz, H. and Durrheim, R.J. (2014b). BX CCBO in-situ stress measurements at earthquake prone areas in South African gold mines– a summary of mini-workshop on 13 Feb 2014. Proceeding of the American Rock Mechanics Association annual symposium, ARMA2014, Minneapolis, CD-ROM, paper number 14-7438.
Ogasawara, H.Y., Manzi, M., Durrheim, R. and Ogasawara, H. (2017). Calibration of the seismic velocity structure and understanding of the fault formation in the environs of the Orkney M5.5 earthquake, South Africa. Abstracts AGU 2017 Fall Meeting, #S51A-0570.
Rickenbacher, M. (2018). Geological and geotechnical rock mass model from two deep DSeis boreholes drilled at Moab Khotsong. MSc thesis. ETH Zurich, Switzerland.
Rusley, C., Onstott, T.C., Liang, R. Higgins, J.A., Slater, N.W., Ogasawara, H., Cason, E.D., Sherwood, B., Lollar, B., Wiersberg, T., Zimmer, M., van Heerden, E., Kieft, T.L., Freese, B., Liebenberg, B. and Esterhuizen, V.H. (2018). Exploring the limits of life in a South African deep subsurface brine. Abstract B23E-2552 AGU 2018 Fall meeting, Washington DC, 11 December 2018.
Sugawara K. and Obara Y. (1999). Draft ISRM suggested method for in situ stress measurement using the compact conical-ended borehole overcoring (CCBO) technique. International Journal of Rock Mechanics and Mining Sciences, 36, 307–322.
Van Aswegen, G. (2017). Keynote Lecture: Seismic sources and rockburst damage in South Africa and Chile. Proceedings of the 9th International Symposium on Rockbursts and Seismicity in Mines (RaSiM9). Vallejos, J.A (ed.). Feyser Impresores. Santiago. pp. 72–87.
Voosen, P. (2017). Deep in a South African gold mine, scientists drill for the heart of an earthquake. Science. aan6905. 31 May 2017.
Wechsler, N., Van Aswegen, G., Yabe, Y., Mngadi, S., Kamhaji, L., Ward, A., Morema, S., Durrheim, R., Ogasawara, H. and ICDP DSeis team. (2018). Recovery of ruptures from seismogenic zone at Cooke 4 mine (DSeis - ICDP scientific drilling project in the South-African gold mines). Abstract EGU 2018-9721, Vienna, 12 April 2018.
Wiersberg, T., Zimmer, M., Kujawa, C., Liebenberg, B., Ogasawara, H., Onstott, T.C., Cason, E., Vermeulen, Jan-G and van Heerden, E. (2019). Investigations on fault zone gases in South African gold mines. Abstract EGU2019-5670, SSP1.2/CL1.32/EMRP3.11/GD2.9/GMPV1.7/NH5.12/
TS1.4, 7-12 April 2019, Vienna.
Yabe, Y., Nakatani, M., Naoi, M., Philipp, J., Janssen, C., Watanabe, T., Katsura, T., Kawakata, H., Georg, D. and Ogasawara, H. (2015). Nucleation process of an M2 earthquake in a deep gold mine in South Africa inferred from on-fault foreshock activity, Journal of Geophysical Research, 120, 5574–4495.
Yabe, Y., Abe, S., Ito, T., Ishida, A., Sugimura, K., Kanematsu, M., Higashi, M., Tadokoro, R., Ogasawara, H., Funato, A., Kato, H., Watson, B., Mngadi, S., Durrheim, R., Hofmann, G. and Scheepers, L. (2019). In-situ stress around earthquake source faults in and beneath South African deep gold mines. Proceedings of International Conference on Deep Mining 2019. This volume, SAIMM, Johannesburg.
Yamamoto, K. (2009). A theory of rock core-based methods for in-situ stress measurement, Earth Planets Space, 61, 1143–1161.
Ziegler, M., Rickenbacher, M., Berset, N., Liebenberg, B., Ishida, A., Sugimura, K., Noda, T., Ogasawara, H., Mngadi, S., Durrheim, R., Ito, T., Funato, A. and the ICDP DSeis team. (2018). Core and borehole logging and stress measurements of a 817 m long borehole drilled from 2.9 km depth toward the Moab Khotsong 2014 M5.5 aftershock zone (ICDP DSeis project in South Africa). Abstract EGU2018-10377, Vienna, 12 April 2018.




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