A relationship between the carbon and hydrogen content of coals and their vitrinite reflectance

An empirical relationship between carbon and hydrogen contents of coals and their measured vitrinite reflectances Rv, max (henceforth Ro) determined from published data for 210 samples of Australian coals from more than 60 different seams, shows that Ro depends upon both the carbon and hydrogen content via the equation %Ro = − 5.035 + 0.0804%C − 0.184%H. This equation allows prediction of the change in Ro when the carbon and/or hydrogen content vary. The equi-reflectance lines plotted on a Seyler chart using this equation allow prediction of the variable suppression of Ro caused by changes in hydrogen content.