Microscopic Studies

  • Vahid Tavakoli
Part of the SpringerBriefs in Petroleum Geoscience & Engineering book series (BRIEFSPGE)


Microscopic observations are one of the main sources of information for geological studies. This is more important in core analysis with limited macroscopic samples. Routine microscopic studies of a core sample include petrographical analysis to understand facies properties and diagenetic processes, paleontological studies for absolute age dating, X-ray diffraction for mineral identification (especially clays), scanning electron microscopy equipped with energy dispersive spectroscopy for pore and pore throat determination, mineral identification, and elemental analysis. The static reservoir properties of a sample depend completely on primary (facies) or secondary (diagenesis) characteristics of the rocks. The rock mineralogy, constituents, sedimentary environment, microscopic porosities, cements, compaction features, and many other parameters are gained by study of a rock sample under a polarizing microscope. They are recorded on standard sheets and compared with other rock properties derived from routine or special core analysis sections. Paleontological studies are used for absolute age dating and make it possible to correlate the strata in a chronostratigraphic framework. Such a framework is integrated with other microscopic and macroscopic geological data and provides the reservoir zonation scheme and understanding of reservoir geometry. Fine-size minerals, especially clays, are identified by the X-ray method. They play a vital role in reservoir properties and future drilling in the field. Pore types and pore throats determine the fluid flow properties and major rock types of the reservoir. They have a major effect on reservoir heterogeneity. Final results are combined with other sources and characterize the geological role in micro and regional scale distribution of reservoir properties.


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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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