The regular alternation of diatom ooze with diatom-bearing terrigenous sediment within the postglacial laminated unit from ODP Site 1098, Palmer Deep Basin I, does reflect the modern seasonal variation in flux to the seafloor in the west Antarctic Peninsula region, as influenced by modern oceanographic conditions (Hofmann et al., 1996) and recorded in sediment traps (Leventer, 1991). The detailed microscopic fabric analyses presented here lends support to the hypothesis that this sequence is predominantly composed of annually laminated sediments. However, our investigations have revealed that there are at least two scales of variation between the diatom ooze and the diatom-bearing terrigenous components—centimeter scale and submillimeter scale. Both scales of variation could be attributed to interannual variability, which would bring the average sedimentation rate of this interval more into line with the AMS radiocarbon-derived sedimentation rate, which would lead to the conclusion that these sediments are not varves. There is also microbioturbation that is not apparent from visual core inspection. Caution should be exercised when using this interval to reconstruct paleoceanographic and paleoclimatic variability during the deglaciation of this region of Antarctica. High-resolution study of the diatom assemblage sequences within both the diatom ooze and diatom-bearing terrigenous laminae, combined with microscale fabric analyses, will clarify whether the sediments are varves or interannual layers.