Accessories observed from residues prepared for examination of foraminifers are summarized in Table AT1. Samples below Sample 188-1166A-12R-CC are not included unless they contain accessories of significance. In this case, coal is common in Sample 188-1166A-14R-CC and wood is common in Sample 17R-CC, which is the uppermost limit of woody fragments that are commonly present below this depth. The presence of what appears to be bone in Sample 188-1166A-11R-1, 47-50 cm, is noteworthy. Sponge spicules and echinoid spines are indicators of fully marine conditions even in the absence of other marine indices such as foraminifers. Pyrite consists of crystalline aggregates and appears to be detrital in origin, as some is found in detrital sandstone grains. Black coal is probably detrital and is likely derived from the Permian Amery Group coals of the Prince Charles Mountains or underlying Lower Cetaceous sediment. Wood is taken to be from nearby sources or in situ, a component of the local depositional environment. Residues usually are large and of terrigenous material in this section. Most are moderately sorted, and a comment on sorting is made only if it is notably poor or good.
Sponge spicules are conspicuous in modern sediments of Prydz Bay. However, with the exception of the 63- to 125-µm size fraction in Samples 188-1166A-1R-CC and 2R-CC and a horizon rich in sponge spicules (with simple diactinellid monaxon spicules to ~10 mm long) that occurs in Sample 188-1166A-2R, 72-73 cm, sponge spicules are either absent or very minor constituents at this site.
Sample 188-1166A-11R-1, 47-50 cm, contains what appears to be fragmented bone. Stereobinocular microscope examination of a fragment suggests that it has significant detail and deserves separate examination during shore-based studies. The fragments need to be reassembled, as the drilling process seems to have shattered the original into several tens of fragments.
Black coal fragments are present throughout the sequence, and based on observation, most are genuine coal that probably originated in the Permian Amery Group sequence of the Prince Charles Mountains region. A few trilete and bisaccate pollen or spores were recovered from diatom preparations of Samples 188-1166A-16R-2, 140-141 cm, and 16R-CC. The bisaccate forms are likely to be Permian; however, the source of the trilete is not as clear. They could be from the same source as the wood fragments in Sample 188-1166A-17R-CC.
Wood fragments, <0.5 mm long, first appear downhole at Sample 188-1166A-17R-CC (the top of lithostratigraphic Unit III) and in several samples below that. Under the microscope, the small fragments retain flexibility and orange-brown color when wet. Wood and cuticle details are clearly visible in mounted slides of the material. These wood fragments are different in color and preservation from the woody structure that is visible in some of the black coal fragments that accompany most samples.
In Sample 188-1166A-25R-2, 0-5 cm, there are fragments as large as 8-9 mm in diameter of dark brown lignified wood, which contrasts strongly with the Permian black coal. Woody structures are well preserved. Sample 188-1166A-27R-CC consists mostly of wood in fragments as large as 20 mm. The rest is quartz sand and mica, suggesting deposition in a swamp environment. There is ample wood that is well enough preserved to allow reconstruction of the vegetation at the time.
The wood fragments provide clear evidence of coeval terrestrial vegetation during deposition of Samples 188-1166A-17R-CC to 28R-CC, which immediately underlie material that is dated on other bases as latest Eocene-earliest Oligocene in age.
The features of this material contrast with descriptions of Lower Cretaceous coals recovered from Hole 741A during Leg 119, Cores 119-741A-5R to 14R in the interval 23.9-128.1 mbsf, indicating strongly that the lignitic matter encountered in Hole 1166A is Tertiary (or possibly Upper Cretaceous) material close to its origin. The woody tissue is very well preserved in many samples.
Descriptions of the Lower Cretaceous coals encountered during Leg 119 indicate that they are different (Turner and Padley, 1991). The core descriptions in the Leg 119 Initial Reports volume (Barron, Larsen et al., 1989) give much more information. The coals recovered during Leg 119 are black, apparently rich in charcoal, and lack obvious woody tissues. The Leg 119 Shipboard Scientific Party (1989b) summary of the occurrence recorded the coal as allochthonous "finely disseminated organic matter and carbonized plant fragments" and referred to "dark, organic-rich sediment." In Hole 1166A material, woody material is very abundant, still flexible when wet, and brown lignitic rather than black coal.