How is vitrinite reflectance measured?
The reflected light intensity is measured with either a photometer, a spectrophotometer or with a digital camera fitted to the microscope. The system is calibrated with special Vitrinite Reflectance Standards, supplied by CRAIC. The sample is then placed on the sample stage and brought into focus.
What is vitrinite reflectance in oil and gas?
1. n. [Geology] A measurement of the maturity of organic matter with respect to whether it has generated hydrocarbons or could be an effective source rock. See: generation, geochemistry, geologic time scale, kerogen, maturity, source rock, vitrinite.
What is vitrine reflectance?
Vitrinite reflectance (Ro) Vitrinite reflectance is the proportion of incident light reflected from a polished vitrinite surface. Vitrinite is a maceral (an organic component) of coal. As vitrinite is heated in the earth during burial, it systematically changes its reflective properties.
How is vitrinite reflectance used as an indication of maturity of source rocks?
The key attraction of vitrinite reflectance in this context is its sensitivity to temperature ranges that largely correspond to those of hydrocarbon generation (i.e. 60 to 120 °C). This means that, with a suitable calibration, vitrinite reflectance can be used as an indicator of maturity in hydrocarbon source rocks.
What is the meaning of%vitrinite reflectance?
Vitrinite reflectance is a measure of the percentage of incident light reflected from the surface of vitrinite particles in a sedimentary rock. It is referred to as %R o.
How do you use vitrinite reflectance as a maturity parameter?
Look for Vitrinite Reflectance as Maturity Parameter by Mukhopadhyay and Dow (2007), for further details. The most common application of the increase of vitrinite reflectance is mapping isoreflectance contours to depict local and regional variation of maturation.
How can I measure the vitrinite reflectance of coal?
ISO 7404-5 and ASTM D2798 both state that measuring the vitrinite reflectance of coal is to be done with a specially configured microscope using a calibrated photometer. The microscope is configured for incident illumination with green light where the illuminating light may be either plane-polarized or not.
What does vitrinite look like under microscope?
Under a microscope, it has a shiny appearance and is derived from the cell-wall material or woody tissue of plants. Since vitrinite changes predictably with heating (over geological time periods), vitrinite reflectance levels are a reliable measurement of a coal sample’s thermal maturity thus its value as a source of energy.