1887

Abstract

Summary

Microseismic waveform data can provide detailed information on reservoirs. In our work, we re-process recordings of selected microseismic events from the geothermal reservoir Basel-1, in order to better characterize the reservoir.

Coherent reflected phases are identified by clusterwise analysis of the waveforms, since clustered events illuminate structures in a similar way. Applying the Fresnel Volume Migration to several clusters, we image zones of high reflectivity in the vicinity of the borehole. From the ratio of reflected to direct wave, we assign a value of apparent reflectivity to each imaged reflector. Correcting for effects due to different ray paths of direct and reflected waves, we map the estimated reflection coefficients. Comparing the estimated values to the frequency- and angle-dependent reflection coefficient at a single fluid layer, we map the fracture width. Some of the reflectivity values indicate complex fluid-filled fractured zones, rather than single fractures. Under linear slip condition, a value for the normal compliance of the reservoir can be determined.

In the Basel reservoir, we observe reflection coefficients of about 0.1, which means effective fracture widths in the range of centimeters.

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/content/papers/10.3997/2214-4609.201601263
2016-05-31
2020-06-02
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References

  1. Aki, K. and Richards, P.G.
    [2002] Quantitative Seismology.University Science Books, 2 edn.
    [Google Scholar]
  2. Buske, S., Gutjahr, S. and Sick, C.
    [2009] Fresnel Volume Migration of single-component seismic data. Geophysics, 74(6), WCA47–WCA55.
    [Google Scholar]
  3. Dyer, B., Schanz, U., Ladner, F, Haring, M. and Spillman, T.
    [2008] Microseismic imaging of a geother-mal reservoir stimulation. The Leading Edge, 27(7), 856–869.
    [Google Scholar]
  4. Haring, M.O., Schanz, U., Ladner, F and Dyer, B.C.
    [2008] Characterisation of the Basel 1 enhanced geothermal system. Geothermics, 37(5), 469–495.
    [Google Scholar]
  5. Kummerow, J., Shapiro, S.A., Asanuma, H. and Haring, M.
    [2011] Application of an Arrival Time and Cross Correlation Value-based Location Algorithm to the Basel microseismic Data. Extended Abstracts DVD of the 73rd EAGE Conference & Exhibition incorporatingSPE EUROPEC, Artikel Nr. P193 (5 S.). EAGE Publications bv.
    [Google Scholar]
  6. Oelke, A., Alexandrow, D., Abakumov, I., Glubovskikh, S., Shigapov, R., Krüger, O.S., Kashtan, B., Troyan, V.N. and Shapiro, S.A.
    [2013] Seismic reflectivity of hydraulic fractures approximated by thin fluid layers. Geophysics, 78(4), T79–T87.
    [Google Scholar]
  7. Reshetnikov, A., Kummerow, J., Asanuma, H., Haring, M. and Shapiro, S.A.
    [2015] Microseismic reflection imaging and its application to the Basel geothermal reservoir. GEOPHYSICS, 80(6), WC39–WC49.
    [Google Scholar]
  8. Rusu, A.
    [2012] Processing of microseismic data for imaging the Basel geothermal reservoir. Master’s thesis, Berlin, Freie Universität Berlin, BSc, 2012.
    [Google Scholar]
  9. Schoenberg, M.
    [1980] Elastic wave behavior across linear slip interfaces. Journal of the Acoustical Society of America, 68(5), 1516–1521.
    [Google Scholar]
  10. Shearer, P.M.
    [2009] Introduction to seismology.Cambridge University Press.
    [Google Scholar]
  11. Yu, C. and Shapiro, S.A.
    [2015] Rock Physics Constrained Estimation of Shale Anisotropy for Microseismic Processing - From VTI to ORThorhombic. Extended Abstracts DVD of the 77th EAGE Conference & Exhibition incorporating SPE EUROPEC, We P507. EAGE Publications bv.
    [Google Scholar]
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