It is not uncommon to observe that vitrinite retlectance results from coal samples with equal maturity and type of vitrinite are distributed over a range of up to 0.20-0.25 %Rm for maturity levels around 0.5 to 1.0 %Rm. It is demonstrated that the variations may be related to microlithotype composition of the samples and accordingly to the depositional environment. A practical consequence is that uncritical interpretation of data may gi ve misleading results. However, improved precision can be obtained by increasing the number of samples, and by considering microlithotype composition.
Scatter in vitrinite reflectance data from coal samples in North Sea wells