Reflectance data from vitrinite and bituminite in the Kimmeridge Clay Formation supporting the ICCP Identification of Dispersed Organic Matter Working Group round robin exercises from 2016 to 2020

Three round robin exercises (RRE) aimed at characterizing bituminite and testing the reproducibility of random vitrinite (VRo %) and bituminite (BitRo %) reflectance measurements of the Kimmeridge Clay Formation were conducted in 2016, 2018, and 2020. This work was conducted by the Identification of Dispersed Organic Matter Working Group (IDOM WG) of the International Committee for Coal and Organic Petrology (ICCP). Samples collected from Kimmeridge Bay and Filey Bay outcrops and the 16/17-14 well in the Tiffany oil field, Viking Graben, North Sea, UK, were analyzed by 19 to 23 participants in 15 to 17 laboratories from 14 to 15 countries. Mean VRo values, including outliers in the three RRE, range from 0.47 to 0.71%, confirming the immature to thermally mature nature of the KCF samples used. Mean random BitRo %, including outlying values, varied in all three RRE from 0.19 to 0.35%. All reflectance data are reported anonymously.