The organic matter is dominantly vitrinite. A small proportion of the vitrinite may have grown in a marginal marine setting, but most appears to have grown inland. The coal and shaly coals show assemblages typical of ombrogenous settings, although the abundance of minerals suggests a low-moor inland setting rather than a high moor. The presence of fungal tissues suggests that wood-rotting fungae were able to live in the areas that were the source of the woody tissues. This is consistent with an origin from an inland rather than a marginal marine setting. However, most of the wood tissues are relatively intact, and the extent of fungal attack appears, overall, to have been small. The preservation of the wood structures within the large isolated wood fragments is generally better than in the coals and shaly coals.
Some coaly intraclasts are undoubtedly present (Plate P11, fig. 3 and fig. 4). The root tissues, such as those figured in Plate P13, figure 3 and figure 4, suggest that some in situ plant tissue are present. The preservation of some of the cutinite is also indicative of minimal transport for at least some of the organic matter.
Fusinite and semifusinite are restricted to two samples. Both of these components tend to float, so lack of these macerals could be due to a low tendency for sinking in the water column. However, it is also possible that the horizons that contain these two macerals represent relatively rare forest fire events in the source areas.
Marine liptinite is a relatively minor component of the organic matter assemblages. The general paucity of phytoplankton may suggest relatively low productivities in the overlying water columns.