Macroscopic Studies

Chapter
Part of the SpringerBriefs in Petroleum Geoscience & Engineering book series (BRIEFSPGE)

Abstract

Macroscopic core studies investigate large-scale core properties that are not detectable by any other methods. A macroscopic description of the core is the final step in geological observations and reveals the remaining rock properties between the plugs. As plugging is not possible or vital in some important lithologies such as shales or anhydrites recording these variations and involving them in any interpretation is crucial. Building both conceptual and numerical reservoir models without involving macroscopic core properties leads to vital mistakes in reservoir characterization. Routinely, there are two stages of macroscopic core description. The first stage is after core cleaning for the first evaluation of the rocks, helping microscopic considerations and selecting primary samples for various analyses. The second stage is at the end of geological studies. Cores are slabbed prior to description. The fresh uncontaminated surface of the rock is available at this time. Core-scale rock properties are recorded on standard sheets that were prepared prior to description. These include but not limited to missed rock layers, rock color, sedimentary structures, compaction-related features such as stylolites and solution seams, bedding and stratal surfaces, intraclasts and rip-up clasts, large and trace fossils, visual porosities, fractures and their properties, fining and coarsening upward trends, and oil staining. The recorded parameters are illustrated on a core description log with appropriate scale. The results are integrated with microscopic geological studies as well as routine core analysis data to achieve the best interpretations and build an accurate reservoir model.

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  1. 1.School of Geology, College of ScienceUniversity of TehranTehranIran

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