Coals and shaly coals are present in a number of samples from Hole 1109D in the deeper part of the section. These appear to be hypautochthonous in origin. However, it is possible that the samples are themselves part of large peat intraclasts, but this does not appear to be likely. The coals and shaly coals are typical of Tertiary peats and show affinities to the Miocene coals that are widely distributed through Papua New Guinea and southeast Asia. Liptinite is abundant to major within these coals, but they are dominated by vitrinite. Inertinite is present as small amounts of funginite (sclerotinite).
The vitrinite occurs both as telovitrinite and detrovitrinite (Plate P9, fig. 1, fig. 2, fig. 3, and fig. 4; Plate P10, fig. 1, fig. 2, fig. 3, and fig. 4; Plate P14, fig. 2). Detrovitrinite is more widely distributed than telovitrinite, but the large size of the telovitrinite phytoclasts means that it is more abundant overall within the coals. No major differences in reflectances between detrovitrinite and telovitrinite were found (cf. Plate P9, fig. 1; Plate P9, fig. 3). This is probably because most of the detrovitrinite represents isolated cell fillings from woody tissue, and this is the component used in vitrinite reflectance measurements made on the telovitrinite.
A range of liptinite macerals is present, sporinite, resinite, suberinite, cutinite, and liptodetrinite. Resinite and resin-related liptodetrinite are generally the most abundant. However, the larger liptinite phyterals are more prominent features, for example, the strongly fluorescing suberinite seen in Plate P10, figure 4. Inertinite within the coals is effectively confined to funginite (sclerotinite). Plate P10, figure 1, illustrates a large teleutospore seen in transverse section. Plate P9, figure 1, also contains some less easily distinguished funginite.
Plate P11, figure 3 and figure 4, illustrate a small peat intraclast occurring within a sandy sediment. The coal type is similar overall to that illustrated in Plate P9, figure 1 and figure 2. In this case, the intraclast origin is clear from the discordant nature of the bedding. However, peat clasts tend to be platy, and it is possible that the other occurrences of coal and shaly coal are also intraclasts, as the contact with the surrounding lithologies was not seen.