1887
Volume 22, Issue 1
  • ISSN: 0812-3985
  • E-ISSN: 1834-7533

Abstract

Boreholes drilled in the search for oil in the Vulcan Sub-basin (Timor Sea, North West Shelf, Australia) commonly exhibit an elliptical cross-section believed to be the result of wellbore failure known as borehole breakout. Breakouts form by compressional shear failure in response to stress concentration around the borehole due to the prevailing stress. The bore wall becomes elongated in the direction of least horizontal compressive stress. The orientation and shape of the breakouts are measured by the four-arm dipmeter tool. The azimuths of the long axes of breakouts in the Vulcan Sub-basin show a reasonably consistent 130-170°N trend implying that maximum horizontal compressive stress (SH) is oriented 040-080°N.

This NE-ENE SH orientation in the Vulcan Sub-basin is not controlled by compression transmitted from the nearby Australia/Banda Arc collision zone. However, it is consistent with theoretical models of stress distribution in the Indo-Australian plate based on the plate-driving forces at all of its boundaries. The present SH orientation is consistent with either strike-slip or normal movement on the pre-existing NE-trending faults in the basin.

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1991-03-01
2026-01-21
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References

  1. Abbott, M., and Chamalaun, F., (1981). ‘Geochronology of some Banda Arc volcanics’. In: Barber, A., and Wiryosujono, S., (eds.) The geology and tectonics of Eastern Indonesia, Geological Research and Development Centre, Bandung, Indonesia, Sp. Pub., 2, 253-268.
  2. Audley-Charles, M. G., (1986). ‘Rates of Neogene and Quaternary tectonic movements in the Southern Banda Arc based on micropalaeontology’. J. Geol. Soc. Lond., 143, 161-175.
  3. Bell, J. S., (1990). ‘Investigating stress regimes in sedimentary basins using information from oil industry wireline logs and drilling records’. In: Hurst, A., Lovell, M.A., and Morton, A.C. (eds.) Geological applications of wireline logs, Geol. Soc. Sp. Pub., 48, 305-325.
  4. Cardwell, R. K., and Isacks, B. L., (1978). ‘Geometry of the subducted lithosphere beneath the Banda Sea in eastern Indonesia from seismicity and fault plane solutions’. J. geophys. Res., B83, 2825-2838.
  5. Chamalaun, F, Lockwood, K., and White, A., (1976). The Bouguer gravity field of eastern Timor’. Tectonophysics, 30, 241-259.
  6. Cloetingh, S., and Wortel, R., (1986). ‘Stress in the Indo-Australian plate’. Tectonophysics, 132, 49-67.
  7. Dart, R. L., and Zoback, M. L, (1989). ‘Wellbore breakout stress analysis within the central and eastern continental United States’. Log Analyst, 30, 1, 12-25.
  8. Friedrich, J., McCaffrey, R., and Denham, D., (1988). ‘Source parameters of seven large Australian earthquakes determined by body waveform inversion’. Geophys. J., 95, 1-13.
  9. Hillis, R. R., (1990). ‘Post-Permian subsidence and tectonics, Vulcan Sub-basin, North West Shelf, Australia’. In: Pacific Rim Congress 90 Proc, V. II, 203-211.
  10. Jacobson, R. S., Shor, Jr., G. G., Kieckhefer, R. M., and Purdy, G. M., (1978). ‘Seismic refraction and reflection studies in theTimor-Aru Trough system and Australian continental shelf. Am. Ass. Petrol. Geol. Mem., 29, 209-222.
  11. Johnston, C. R., and Bowin, C. Q, (1981). ‘Crustal reactions resulting from the mid Pliocene-Recent continent-island arc collision in the Timor region’. Bur. Miner. Resources J. Aust. geol. geophys., 6, 223-243.
  12. Mardia, K. V., (1972). Statistics of directional data. Academic Press, London and New York, 357pp.
  13. Minster, J. B., and Jordan, T. H., (1978). ‘Present-day plate motions’. J. geophys. Res., B83, 5531-5354.
  14. Pattillo, J., and Nicholls, P. J., (1990). ‘A tectonostratigraphic framework for the Vulcan Graben, Timor Sea region’. Aust. Petrol. Explor. Assoc. J., 30, 27-51.
  15. Plumb, R. A., and Hickman, S. H., (1985). ‘Stress-induced borehole elongation: a comparison between the four-arm dipmeter and the borehole televiewer in the Auburn geothermal well’. J. geophys. Res., B90, 5513-5521.
  16. Richardson, M., Solomon, S. C, and Sleep, N. H., (1979). ‘Tectonic stress in the plates’. Rev. geophys. space phys., 17, 981-1019.
  17. Schlumberger (1981). Dipmeter interpretation. V. 1, Schlumberger Educational Services.
  18. Veevers, J. J., (1974). ‘Sedimentary sequences of the Timor Trough, Timor, and the Sahul Shelf. In: Veevers, J.J., Heirtzler, J.R., et al. (eds.) Initial Rep. Deep Sea Drill. Proj., 27, 567-569.
  19. Whitford, D. J., and Jezek, P. A., (1982). ‘Isotopic constraints on the role of subducted sialic material in Indonesian island-arc magmatism’. Geol. Soc. Am. Bull., 93, 504-513.
  20. Woods, E. P., (1988). ‘Extensional structures of the Jabiru Terrace, Vulcan Sub-basin’. In: Purcell, P.G., and R.R. (eds.) The North West Shelf, Australia, Proc. Petrol. Explor. Soc. Aust. Symp., Perth 1988, 311-330.
  21. Zoback, M. D., Moos, D., Mastin, L., and Anderson, R. N., (1985). ‘Well bore breakout and in situ stress’. J. geophys. Res. B90, 5523-5530.
  22. Zoback, M. L., and Zoback, M. D., (1989). ‘Tectonic stress field of the continental United States’. In: Pakiser, L.C., and Mooney, W.D. (eds.) Geophysical framework of the continental United States, Geol. Soc. Am. Mem., 172, 523-539.
  23. Zoback, M. L., et el., (1989). ‘Global patterns of tectonic stress’. Nature,341, 291-298.
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  • Article Type: Research Article
Keyword(s): borehole breakouts; in situ; plate collision; stress; Vulcan Sub-basin

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