We use cookies to ensure that we give you the best experience on our website. You can change your cookie settings at any time. Otherwise, we'll assume you're OK to continue.

Durham University

Department of Earth Sciences

Petrography and Microscopy


Petrographype•trog•ra•phy — pɛˈtrɒgrəfɪ

n. the branch of science concerned with the composition and properties of rocks

Petrography is a fundamental part of the Earth Sciences, which plays a role in much of the research that takes place within the Earth Sciences department. It is also a core component of teaching at all levels of the within the undergraduate programme. This page provides further information on the petrography and microscopy facilities in the Department of Earth Sciences, together with information on their use in its teaching and research.


Specialist infrastructure

The Department of Earth Sciences has a dedicated Microscopy and SEM laboratory, which contains a significant proportion of our petrographic imaging equipment, and is used by researchers in almost all research areas. However, many research groups also have their own specialist equipment funded by grants and consortia.

  • The GeoPOP3 Research Consortium will use the laboratory and especially the SEM for several of the research themes with 100% fEC funding.
  • The Rock Mechanics Laboratory contains a state-of-the-art microscope purchased in 2013 for the analysis of rock deformation samples.

Professional services

The facility offers a full petrological service for industry with fast turn around times for SEM analysis of samples. We offer a unique facility in that samples need not be coated or polished to use the SEM-EDS and hence preserve sample integrity.

Related Facilities

In addition to the facilities present within the Earth Sciences department, staff and postgraduate students have access to microscopy equipment within other departments across the University. In particular, the Scanning Electron Microscopy facility based in the Physics department:

Durham GJ Russell Microscopy Facility


Petrography is used in some capacity in a many research groups within the Earth Sciences department, as a tool for phase analysis, textural analysis, and quantitative analysis. This section explores the use of Petrography within these research groups.

Phase IdentificationTextural AnalysisQuantitative Analysis

Petrography in

Phase Analysis

— identifying minerals/clasts within a rock as a hand specimen or in thin section.

Textural Analysis

— examining the texture of a rock, the arrangement of the minerals/clasts within the sample.

Quantitative Analysis

— e.g., grain size analysis, image analyses, point counting.

The Structural Research Group at Durham make extensive use of the microscopy facilities across all three areas. Investigation of rock texture at the outcrop, hand specimen and thin section scale yeild information on the deformational history of a region that is of interest within Structural Research. In addition, the closely associated Rock Mechanics Laboratory uses petrography to examine samples produced using the LVHRS apparatus, in order to understand the mechanisms of faulting within the crust.

Petrographic analysis in Sedimentological research is mainly used to provide estimates of the pore space, composition, and paragenesis of a sample. Image analysis for quantitative estimates of the pore space within a sample,for example, contribute to estimates of reservoir potential and fluid overpressure.

Micropalaeontological research is undertaken largely through the use of microscopes, both reflected light and transmitted light. At Durham, the Palaeoecosystems group uses the Microscope suite as well as the table-top SEM. In addition, the group have dedicated microscopes in the palaeoecosystems laboratory located on Level 1 in the Arthur Holmes Building.

Phase analysis of extrusive, intrusive and erupted igneous rocks underpins much of the research undertaken by members of the Volcanology Group. Quantitative analysis is also heavily used; for example: SEM analysis of volcanic ash provides insights into the health hazard of volcanic eruption, while point counting for mineral proportions allows estimation of trace element partitioning in intrusive igneous bodies


"The best geologist is the one who has seen the most rocks."(H. H. Read, 1940)

The Earth Sciences department offers a range of taught undergraduate degree programmes. Petrology and petrography form core components throught these but significantly at Level 1 and Level 2. The Level 1 Earth Materials module teaches students the principles of crystallography and petrology along with the basic methods to identify minerals in hand specimen or under a petrographic microscope. These skills are then applied further in Level 2 and 3 modules to develop student understanding of the physical processes that shape the Earth.