MSc. Carla Viviane Araujo
Petrobras - Cenpes/GEOQ/PDEXP
Av. Horï¿½cio Macedo, 950 - Cidade Universitï¿½ria
Ilha do Fundï¿½o - Rio de Janeiro, Brazil
This working group was established in 1988 at the ICCP Meeting in Aachen. The aim was to look at the various thermal indices (i.e., vitrinite reflectance, fluorescence, thermal alteration index, Rock-Eval, volatile matter, elemental composition) in respect to their sensitivity at different rank levels, their limitations and the correlations and comparabilities amongst them.
The objectives of the working group moved between 1994 and 1998 to the standardization of fluorescence measurements and are now back to the original ones, incorporating other geochemical thermal indices such as isomerization ratios from biomarkers. Exercises from 2000-2010 looked at all of these approaches - comparison amongst different maturity parameters and standardization of fluorescence measurements on liptinites.
The samples analysed over the years, exercises performed, and publication of results are as follows:
Series of coal and oil shales taken at different depth
- Pradier, B., (1994). ICCP Interlaboratory Exercise on Organic Thermal Markers. AAPG 1994 Annual Convention, Denver, Colorado, June 12-15, 1994.
Marine samples of different maturity
- Pradier,B., Vieth-Redemann, A., Araujo, C.V., Kalkreuth, W., Gomez Borrego, Hagemann, H., Hufnagel, W., Koch, M., Koch, J., Kuili, J., Laggoun-Defarge, F., Newmann, J., Petersen, H.I., Spanic, D., Stasiuk, L., Suarez-Ruiz, I., Thompson-Rizer, C., Wang, J., Wilkins, R., (1998). ICCP Interlaboratory Exercise on the Application of Microspectral Fluorescence Measurements as Maturity Parameter. 6th Latin American Congress on Organic Geochemistry, Margarita Island, Venezuela, October 18-22, 1998 (Conference CD-ROM).
- Araujo, C.V., Vieth-Redemann, A., Pradier, B., Kalkreuth, W., Gomez Borrego, A., Gurba, L., Hagemann, H., Hufnagel, W., Koch, M., Kuili, J., Laggoun-Defarge, F., Lo, H., Newmann, J., Spanic, D., Suarez-Ruiz, I., Thompson-Rizer, C., (1998). ICCP Interlaboratory Exercise on the Application of Microspectral Fluorescence Measurements as Maturity Parameters. Revista Latino Americana de Geoquimica Organica. 4, 41-49.
Joadja coal and equivalent oil shale
- Araujo, C.V., Kalkreuth, W., Condï¿½, V.C., Newman, J., (2000). Interlaboratory Spectral Fluorescence and VRFTM Measurements on Torbanite Samples from Australia. In: Proceedings 7th Latin-American Congress on Organic Geochemistry, Foz do Iguazu, Brazil, 153-156.
- Araujo, C.V., Barbanti, S.M., Condï¿½, V.C., Kalkreuth, W., Macedo, A.C., Newman, J., Pickel, W., Stasiuk, L., Volk, H., (2003). 2003 ICCP Thermal Indices WG: Summary of the 2002 Round Robin Exercise. ICCP News 29, 5-12.
Irati shale (presentation at the 2004 ICCP Meeting and internal report for participants)
Asturian carbonaceous and Posidonia shales
- Araujo, C.V., (2006). Thermal indices WG. Exercise year 2005. ICCP News 37, 17-28.
- ICCP Thermal Indices WG, (2006). Interlaboratory exercise of year 2005/2006. In: Proceedings Latin American Congress on Organic Geochemistry, Extended Abstracts, Salvador, Brazil, 91-96.
Click the heading above to view the presentation given in Victoria.
Oviedo, 2008 - Thermal Indices WG
The results of the TIWG from the years 2007-2008 were presented in Oviedo. The exercises investigated a maturation series comprised by a set of three samples from the Neuquï¿½n Basin, Argentina. Vitrinite reflectance, spectral fluorescence of liptinite, and Rock-Eval analyses were performed. Results for Rock-Eval presented a good correlation, as well as the results for spectral fluorescence, in particular those of participants having recently calibrated their equipment with the ICCP lamp. Correlation of vitrinite reflectance results was very poor due to low vitrinite content of the samples. As it has been proven particularly difficult to find a natural maturation series, the convener proposed a new exercise based on an artificial maturation series produced by the hydrous pyrolysis procedure. As a starting sample the Posidonia shale was suggested.
Belgrade, 2010 - Thermal Indices WG
A presentation on comparison of correction functions and spectral fluorescence curves from telalginite on two different measuring systems (photometer and spectrometer) was given. Corrected spectra obtained by the two different measuring systems presented a very good correlation.
Porto, 2011 and Beijing, 2012 - Thermal Indices WG
Click the heading above to view the presentation given in Beijing.
Three samples (C3- Kappel; C5-Pinnell and D5- Columbia McCoy), representing a natural maturation series from the Devonian of the Appalachian Basin were provided by Robert Ryder (U.S. Geological Survey) for this exercise. Sample sets are distributed in the following way: 1) Sample Set in North America - Paul Hackley, 2) Sample Set in South America - Carla Viviane Araujo, 3) Sample Set in Europe - Angeles Gomez Borrego, and 4) Sample Set in Oceania - Jane Newman.
Participants received three polished blocks and were asked to provide results for mean random vitrinite reflectance and spectral fluorescence measurements of telalginite. Each spectral measurement reported should represent a mean value of about ten single measurements. The mean spectral curve should be adjusted with the correction function obtained by the calibrated ICCP lamp source (exercise of year 1996/97). Seventeen participants provided results for mean random vitrinite reflectance, one participant for VIRF and fourteen for spectral fluorescence measurements. The results have been summarized in a report which is intended to be submitted to the International Journal of Coal Geology or another peer-reviewed journal. This round robin exercise was the last planned for the working group and the effort will be closed following publication of the report.