Colour Spectrophotometry

For years, geologists have used the Munsell colour system to describe the colour of rocks and sediments, visually comparing the hue, lightness, and relative colour purity of earth materials to colour chips. As the demand for a more comprehensive and less subjective colour assessment of sediment is required, Geotek have introduced a state of the art spectrophotometer to mount onto the MSCL-S and MSCL-XYZ systems.

The Konica Minolta colour spectrophotometer can measure reflectance in the very near UV through the visible and into the very near IR range (wavelengths 360-740nm). It provides a rapid and non-destructive method of producing very high resolution image data sets for sediment cores.

The latest MSCL software has been written to permit simultaneous operation of the spectrophotometer with the other MSCL sensors.

Konica Minolta CM-2600d Features & Specification

Illuminating/Viewing system: d/8 (diffused illumination, 8-degree viewing angle), equipped with simultaneous measurement of SCI (specular component included) / SCE (specular component excluded). Also incorporates Numerical UV-Control (NUVC), a technology installed to drastically reduce calibration and measurement procedure time.

Measurement Time/Interval period: Approx. 2 seconds/Approx 4 seconds. High energy xenon flash illumination and the high resolution monolithic dual beam monochromator provide superior optical results.

Measurement/Illumination Area: Two interchangeable measurement apertures MAV: Ø 8mm SAV Ø 3mm. Both provide perfect data correlation and enable image data collection from uneven samples.

Outputs: Spectral data in 10nm bins and Munsell colour can be exported from the Geotek software in text format along with any other MSCL data.

Applications

  • Colour record: Provides a true colour representation of a split core’s surface before oxidation processes can take effect.
  • Paleoclimate/palaeoceanographic records: Reflectivity can act as a reliable proxy for carbonate content. Other compositional elements may also be estimated using specific frequencies or colour parameters as proxies.
  • Core Archives: Cross correlation of overlapping cores for a continuous downhole log.
  • Spectrophotometer Data WindowSpectrophotometer Data Window

    References:

    Jarrard, R.D. & Vanden Berg, M.D. 2006. Sediment mineralogy based on visible and near-infrared reflectance spectroscopy. Rothwell, R.G. New techniques in sediment core analysis. Geological Society, London Special Publications, 267, 129-140.

    Nederbragt, A., et al 2006. Sediment colour analysis from digital images and correlation with sediment composition. Rothwell, R.G. New techniques in sediment core analysis. Geological Society, London Special Publications, 267, 113-128.

    Rogerson, M., et al 2006. Colour logging as a tool in high-resolution palaeocenography. Rothwell, R.G. New techniques in sediment core analysis. Geological Society, London Special Publications, 267, 99-112.

    For further information on the device see Konica Minolta Spectrophotometer CM-2600d or contact us.

MSCL Systems