Abstract
An investigation of ground motion, recorded using broad-band, wide dynamic-range digital seismographs, of large mine tremors from two South African mining districts with different geologic settings, reveals some essential differences in both seismic source and ground motion parameters. In the Klerksdorp district where the strata are offset by major throughgoing normal faults, the largest tremors, with magnitudes ranging as high as 5.2, tend to be associated with slip on these pre-existing faults. Moreover, the seismic source and ground motion parameters are quite similar to those of natural crustal earthquakes. In the Carletonville district, by contrast, where substantial faults do not exist, the large-magnitude tremors appear to result from the failure of relatively intact rock and cause seismic stress drops and ground motion parameters higher than normally observed for natural shocks. Additionally, there appears to be an upper magnitude limit of about 4 in the Carletonville district. Detailed analyses of an exceptionally large event recorded locally from each of these districts serve to highlight these contrasts.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Andrews, D. J.,Objective determination of source parameters and similarity of earthquakes of different size, (Earthquake Source Mechanics, Geophysical Monograph 37 1986) (Maurice Ewing 6) pp. 259–267.
Borcherdt, R. D., Fletcher, J. B., Jensen, E. G., Maxwell, G. L., Van Schaack, J. R., Warrick, R. E., Cranswick, E., Johnston, M. J. S., andMcClearn, R. (1985),A general earthquake-observation system (GEOS), Bull. Seismol. Soc. Am.75, 1783–1825.
Brune, J. N. (1970),Tectonic stress and the spectra of seismic shear waves from earthquakes, J. Geophys. Res.75, 4997–5009. (1971,Correction, J. Geophys. Res.76, 5002.)
Fernandez, L. M. andVan der Heever, P. K.,Ground movement and damage accompanying a large seismic event in the Klerksdorp district, (Proc. 1st Int. Con. on Rockbursts and Seismicity in Mines 1984), (S.A.I.M.M., Johannesburg) pp. 193–198.
Gay, N. C., Spencer, D., Van Wyk, J. J., andVan der Heever, P. K.,The control of geological and mining parameters on seismicity in the Klerksdorp mining district, (Proc. 1st Int. Con. on Rockbursts and Seismicity in Mines 1984), (S.A.I.M.M., Johannesburg) pp. 107–120.
Hanks, T. C. (1977),Earthquake stress drops, ambient tectonic stresses and stresses that drive plate motions, Pure Appl. Geophys.115, 441–458.
Hanks, T. C. andJohnson, D. A. (1976),Geophysical assessment of peak accelerations, Bull. Seismol. Soc. Am.66, 959–968.
Hanks, T. C. andKanamori, H. (1979),A moment magnitude scale, J. Geophys. Res.84, 2348–2350.
McGarr, A.,Some applications of seismic source mechanism studies to assessing underground hazard, (Proc. 1st Int. Con. on Rockbursts and Seismicity in Mines 1984a), (S.A.I.M.M., Johannesburg), pp. 199–208.
McGarr, A. (1984b),Scaling of ground motion parameters, state of stress and focal depth, J. Geophys. Res.89, 6969–6979.
McGarr, A. (1985),Some comments on the nature of Witwatersrand mine tremors, USGS internal report, 19 pp.
McGarr, A., Green, R. W. E., andSpottiswoode, S. M. (1981),Strong ground motion of mine tremors: some implications for near-source ground motion parameters, Bull. Seismol. Soc. Am.71, 295–319.
Scheepers, J. B.,The Klerksdorp seismic network—monitoring of seismic events and systems layout, (Proc. 1st Int. Con. on Rockbursts and Seismicity in Mines 1984), (S.A.I.M.M., Johannesburg), pp. 341–345.
Spottiswoode, S. M.,Source mechanisms of mine tremors at Blyvooruitzicht Gold Mine, (Proc. 1st Int. Con. on Rockbursts and Seismicity in Mines 1984), (S.A.I.M.M., Johannesburg), pp. 29–37.
Spottiswoode, S. M. andMcGarr, A. (1975),Source parameters of tremors in a deep-level gold mine, Bull. Seismol. Soc. Am.65, 93–112.
Tanton, J. H., McCarthy, T. F., andHagan, T. O.,The introduction of stabilizing pillars to reduce rockbursts at Western Deep Levels, Limited, (Proc. 1st Int. Con. on Rockbursts and Seismicity in Mines 1984), (S.A.I.M.M., Johannesburg), pp. 245–252.
van der Heever, P. K.,Some technical and research aspects of the Klerksdorp seismic network, (Proc. 1st Int. Con. on Rockbursts and Seismicity in Mines 1984), (S.A.I.M.M., Johannesburg), pp. 349–350.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
McGarr, A., Bicknell, J., Sembera, E. et al. Analysis of exceptionally large tremors in two gold mining districts of South Africa. PAGEOPH 129, 295–307 (1989). https://doi.org/10.1007/BF00874511
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00874511