Thin Section Petrography


Weatherford Laboratories petrographers have in-depth expertise in conducting thin section petrographic analysis to directly identify grain types and sizes, matrix, and cement and porosity types.

Thin section analyses ultimately benefits the client by providing accurate information about rock types, depositional environment, and diagenesis of the reservoir for both crystalline and noncrystalline (amorphous) materials. We offer a wide variety of preparation options to best suit your individual needs. Our Thin Section Preparation Lab has over 40 years of combined experience in creating custom petrographic products.

Thin Section Mosaics and Petrographic Imaging

Weatherford Laboratories' newest technology, known as thin section mosaic imaging, incorporates a high-magnification petrographic microscope capable of stitching thousands of individual images into one all-encompassing view. As a microscope, it is capable of generating multiple views including plane polarized light (PPL), crossed polarized light (XPL), reflected white light, and reflected UV. We are also capable of providing a variety of magnified photos to suit our client's needs.














Near virtual microscope advantages:

  • Archiving thin section imagery
  • Sharing slides with partners – no need to wait
  • Reduces need for multiple sets of thin sections
  • Great for sample types of limited material
  • Easy to provide digital copies of data to government entities
  • Best of both worlds for viewing macro- and micro-petrological information

Benefits of petrographic analyses:

  • Best way to characterize rock fabric, texture, and sample quality

  • Evaluate the nature of porosity

  • Assist in determining reservoir sensitivity to fluids, pressure, and mechanical stability

  • Applicable to a wide range of sample material (cuttings, PSWC, RSWC, conventional, etc.)

  • Evaluates the distribution of micropores with epifluorescence microscopy

  • Better understanding of provenance, diagenetic history porosity evaluation, and reservoir quality

Compositional and Textural Petrographic Analyses

Our petrographers integrate all available information from a reservoir rock sample through the statistical technique of point counting. By carefully evaluating a matrix of analytical points (typically between 300 and 400) on a thin section of reservoir material under a microscope, we provide a statistically rigorous, quantitative characterization of mineralogy and porosity in conventional rock types. This data may then aid in a variety of interpretations, including the provenance and diagenetic history of the sediments.

Precise characterization of rock types, depositional environment, and diagenesis. Armed with this analysis, clients can make a more informed decision about the
field’s short- and long-term development, whether they are in the early stages of appraising a prospect, developing a promising region, or exploiting an identified or
existing field. The nature of data typically collected and analyzed via point counting analysis includes:


  • Basic mineralogy by volume which includes the percentage of various minerals, detrital and authigenic clays, and cement in the sample

  • Percentage of skeletal and non-skeletal allochem types

  • Fabric and texture

  • Average grain size and range

  • Porosity evaluation such as the percentage of microporosity associated with clays (estimated based on clay content)

  • How the reservoir rock is expected to respond to well logging runs including density, resistivity, and gamma ray

  • Any anticipated formation sensitivity concerns

  • Diagenetic history

Grain size characterization is critical when evaluating depositional processes and controls on reservoir quality. While grain size of unconsolidated sediments can be determined by laser grain size techniques, thin section point count methods must be used on consolidated rock types.

Data can be provided in a Touchstone™ compatible format which the client can use to potentially predict reservoir quality in future wells.

Weatherford Laboratories' petrographers have extensive experience in characterizing clastic and carbonate conventional reservoirs, tight gas sands, shale reservoirs, unconsolidated sands, and heavy oil sands.