The glacial sedimentary units recovered from Transect EG65 are very similar to those recovered from Transect EG68. The cored glacial sediments are divided into three facies: (1) pebble-sized clasts, (2) massive sandy diamicton, and (3) fine-grained diamicton with bioturbation. The sandy fraction in Unit S-1 of Hole SEG48A is composed of angular fragments of quartz, alkali feldspar, amphibole, basaltic lapilli, and shell fragments (Fig. F8).
Preglacial sediments recovered from two sites are particularly interesting. A gray, fine-grained, well-indurated quartzwacke unit (S-1) with rip-up clasts was recovered from Hole SEG38B (Sample 163X-SEG38B-1-1 [Piece 2, 8–27 cm]) (Fig. F9). The rip-up clasts are randomly oriented with irregular, rounded dish shapes. The unit is moderately sorted with grains ranging from clay to medium-sand size cemented by calcite. In thin section, the unit has an isotropic clast fabric of subrounded, low sphericity quartz (50%); clay (8%); subangular to angular grains of calcite (8%), muscovite (1%), and epidote (1%); and carbon flakes (3%). The poorly sorted, random distribution of the irregularly shaped rip-up clasts and high clay and carbon content of this unit suggest deposition under high-energy conditions, possibly as fall-out from a sediment load of a highly concentrated turbidite current suspension. Such a depositional environment, however, is difficult to reconcile with an in situ position between subaerially erupted lavas; therefore the unit might be a glacial clast.
Unit S-2 in Hole SEG80B is a bioturbated, poorly indurated, gray micaceous sandstone with coal flasers (Figs. F7). The fine-grained (silt to medium grained) sandstone is generally well sorted with a porosity value of ~30%. The original planar and small-scale cross-lamination is disturbed by 5- to 30-mm-long, 2–4 mm in diameter vertical and subhorizontal burrows. Coal flasers are abundant as discontinuous drapings with alignment of minute fragments parallel to the bedding. The best examples of coal flasers are found between 19.3 and 30.0 cm in Section 163X-SEG80B-1-1. A fossil wood fragment as large as 2 cm in diameter occurs 35 cm below the top of Unit S-2. The coal has generally high vitrinite reflectance.
In thin section the sediment is dominated by angular grains of quartz with high sphericity (>60%) and feldspar, giving the sandstone an arkosic composition (Fig. F10). Subordinate amounts of muscovite and hornblende and trace amounts of pyrite occur. The heavy mineral assemblage is dominated by zircons. Pyrite is the first authigene phase and is closely connected to organic debris, which is mainly plant fragments. The pyrite is followed by Ti oxides, probably anatase, precipitated in the close vicinity of dissolved titanoferous grains. These authigene phases were cemented by the widespread development of alkali feldspar overgrowths on detrital, dominantly angular feldspar grains. The sparse amount of quartz overgrowths developed contemporary with the prevalent authigene alkali feldspars. After these early diagenetic phases, the sandstone experienced incipient mechanical compaction, as evidenced by slightly bent mica grains and minor grain crushing. Sporadic calcite cementation occurred in the open framework, replacing some of the detrital feldspar grains and occluding porosity locally (Fig. F10). The last diagenetic episode was an intense dissolution of feldspar grains that resulted in high amounts of secondary porosity. The dissolution phase seems selective; preferably dissolving detrital feldspar grains compared to detrital and authigenic alkali feldspar. Dissolution does not seem to have affected calcite, and preferable feldspar dissolution inside calcite cemented areas is widespread. The skeletal grain remnants are not affected by later compaction (Fig. F10), though the authigene cements were only able to stabilize the grain framework in limited amount. Therefore, the sandstone does not seem to have experienced high mechanical compaction and deep burial.
Two samples from Unit S-2 were processed for palynological examination at the Geological Survey of Denmark and Greenland (GEUS). The samples are dominated by tracheids and black coal particles; however, dinoflagellate cysts were recovered from both samples. The dinoflagellate cysts are well preserved and only slightly affected by thermal heating during burial. The density and diversity is low. The dominant species are Oligosphaeridium sp. 1 Nøhr-Hansen 1993 and Circulodinium sp. 1 Nøhr-Hansen 1993, together with a few specimens of Circulodinium distinctum, Leptodinium cancellatum, Microdinium dentatum, Odontochitina operculata, Oligosphaeridium poculum, O. prolixispinosum, Palaeoperidinium cretaceum, Spinidinium styloniferum, and Surculosphaeridium longifurcatum, which is characteristic for the Early Cretaceous. The assemblages correlate with the upper middle Albian Chichaouadinium vestitum Subzone to the lower upper Albian Wigginsiella grandstandica Subzone described from East Greenland by Nøhr-Hansen (1993) and recorded from the Canadian Arctic by Nøhr-Hansen and McIntyre (1998). The well sorted, fine-grained sediment, coal flasers, abundant bioturbation, and presence of dinoflagellate cysts suggest that Unit S-2 was deposited in a relatively calm shallow-marine environment. The angular form of grains and the high content of coal fragments indicate little physical reworking of the sediment before deposition, suggesting that deposition occurred proximally to the source of detritus. After deposition, the sediments in Hole SEG80B suffered little mechanical compaction and heating from the overburden.