1887

Abstract

Summary

Traditional pore pressure prediction methods, which are based on seismic velocities, allow accounting for overpressure generated by compaction disequilibrium. Although several other sources of overpressure has been widely recognized, they are still poorly quantified. This abstract presents a workflow for quantifying the overpressure due to both the lateral strain exerted by a salt diapir and the clay diagenesis (smectite to illite transformation). The former is modelled using geomechanical analytical approach, based on the Geertsma method. The latter is instead derived from geochemical lab tests carried out on bottom-hole cores. The overpressures resulting from the three mechanisms (i.e., under-compaction, lateral strain and clay digenesis) have been superimposed to a post-drilling pore pressure interpretation. The sum of the calculated overpressure fits quite well with the pore pressure interpretation down to a certain depth, below which the considered mechanisms are not enough to fully justify the measured overpressures.

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/content/papers/10.3997/2214-4609.201900510
2019-05-19
2019-12-08
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References

  1. Bowers, G.L.
    [1995] Pore pressure estimation from velocity data: Accounting for overpressure mechanisms besides undercompaction. SPE Drilling & Completion, 10(02), 89–95.
    [Google Scholar]
  2. Eaton, B.A.
    [1975] The equation for geopressure prediction from well logs. Fall Meeting of the Society of Petroleum Engineers of AIME.
    [Google Scholar]
  3. Geertsma, J.
    [1966] Problems of rock mechanics in petroleum production engineering. 1st ISRM Congress.
    [Google Scholar]
  4. Grauls, D.
    [1999] Overpressures: causal mechanisms, conventional and hydromechanical approaches. Oil & Gas Science and Technology, 54(6), 667–678
    [Google Scholar]
  5. Heidari, M., Nikolinakou, M., Flemings, P. and Hudec, M.
    [2015] A Simplified Analysis of Stresses in Rising Salt Domes and Adjacent Sediments. 49th US Rock Mechanics / Geomechanics Symposium.American Rock Mechanics Association.
    [Google Scholar]
  6. Hottman, C.E. and Johnson, R.K.
    [1965] Estimation of formation pressures from log-derived shale properties. Journal of Petroleum Technology, 17(06), 717–722.
    [Google Scholar]
  7. Luo, G., Nikolinakou, M.A., Flemings, P.B. and Hudec, M.R.
    [2012] Geomechanical modeling of stresses adjacent to salt bodies: Part 1—Uncoupled models. AAPG bulletin, 96(1), 43–64
    [Google Scholar]
  8. Nikolinakou, M.A., Luo, G., Hudec, M.R. and Flemings, P.B.
    [2012] Geomechanical modeling of stresses adjacent to salt bodies: Part 2—Poroelastoplasticity and coupled overpressures. AAPG bulletin, 96(1), 65–85.
    [Google Scholar]
  9. Nikolinakou, M.A., Flemings, P.B. and Hudec, M.R.
    [2014] Modeling stress evolution around a rising salt diapir. Marine and Petroleum Geology, 51, 230–238.
    [Google Scholar]
  10. Skempton, A.W.
    [1954] The pore-pressure coefficients A and B. Geotechnique, 4(4), 143–147.
    [Google Scholar]
  11. Zhang, J.
    [2011] Pore pressure prediction from well logs: Methods, modifications, and new approaches. Earth-Science Reviews, 108(1–2), 50–63.
    [Google Scholar]
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