Comparison of open fractures in Ca2 carbonates from outcrop and well, using laser scans, image logs, and 3D-stress

  • Name:

    EAGE Carbonates Workshop 

  • Venue:

    Potsdam, Deutschland

  • Date:

    2017

  • Author:

    Becker, I., Wüstefeld, P., Koehrer, B., Jelinek, W., and Hilgers, C. 

  • Speaker:

    Becker I

  • Understanding the fracture patterns of carbonate reservoirs reduces uncertainties in reservoir characterization.
    This study integrates outcrop and well data to evaluate their comparability in fracture characteristics with a
    focus on Zechstein Ca2 (Stassfurt Formation) carbonates in the Southern Permian Basin, N-Germany. We
    identified a suitable outcrop on the SW margin of the Harz mountains, which can be used as an analog to an
    operated naturally-fractured Zechstein (Ca2) carbonate gas field, some 130 km further to the NW, with a similar
    depositional environment (upper slope) and lithology (dolomite).
    Using our newly developed automated workflow, we derive fracture data from terrestrial laser scanning
    (LiDAR) in addition to manually measured ones, and compare fracture orientations and –frequencies to results
    from subsurface fracture analysis. Furthermore, we determine the dilation tendency of those fractures based on
    the regional stress field and thus, their potential to reactivate and contribute to the flow potential within the
    reservoir.