A thermal maturity map based on vitrinite reflectance of British coals

L Bullock,A Schito,J Parnell,S Corrado,J Armstrong,D Muirhead

doi:10.1144/jgs2019-055

L Bullock, A Schito + Show 4 more

Open Access

https://doi.org/10.1144/jgs2019-055

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Abstract

A compilation of new and previously published vitrinite reflectance (R0) data from Carboniferous coals constitutes the most comprehensive map of reflectance across Great Britain. Values of R0 range from 0.38 to 3.29%, recording an ambient thermal maturity in the early oil window (standard reference point for reflectance studies), modified by elevated heat flow in northern England and along the Variscan orogenic front. The map provides a context for other geological datasets. Supplementary material: A statistical summary of vitrinite reflectance data is available at https://doi.org/10.6084/m9.figshare.c.4529969

Highlights

A compilation of new and previously published vitrinite reflectance (R0) data from Carboniferous coals constitutes the most comprehensive map of reflectance across Great Britain
We present a map of vitrinite reflectance data for Great Britain (Fig. 1)
The standard materials used to calibrate the microscope depend on the coal rank and are spinel with relative reflectance (Rr) of 0.426%, sapphire with Rr of 0.585%, YAG with Rr of 0.905%, GGG with Rr of 1.72 and cubic zirconia with Rr of 3.09

Summary

Methods

There are 14 new analyses in this study, from Inninmore Bay, East Trodigal, High Tirfergus, Uddingston, Arran, Ascog (Bute), Kello Water, Jenkin Beck, Tan Hill, Rowanburn, Wrexham, Hanwood, Pembroke and Midsomer Norton. Samples for new vitrinite reflectance analyses were crushed and mounted in epoxy resin and polished, according to the method of Bustin et al (1990). The vitrinite reflectance (R0) values range from 0.38 to 3.29% (Figs 3 and 4; Table 1 and supplementary material Appendix I). The distribution of values (Fig. 3) shows that a majority of samples have R0 values in the range up to 0.80%. Depths presented are subject to available data in references or obtainable colliery or site information. The depths presented do not account for any uplift, burial or erosion, and may not fully represent the maximum burial experienced by the samples whilst in situ.

Discussion

Findings

44 Washington

Conclusions