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Hadar Guyot: Holes U1377A and U1377B

Two holes were drilled at Hadar Guyot. In Hole U1377A, only a small amount of disturbed sediment was recovered in the core catcher of the first core. The majority of the mixed assemblage within this sample is composed of Pleistocene-age nannofossils, including small Gephyrocapsa and P. lacunosa. The assemblage also includes older, presumably reworked taxa, including D. brouweri and Discoaster triradiatus (late Miocene to Pliocene), as well as D. neohamatus (late Miocene). Two additional samples were taken from Section 330-U1377A-2R-1. Sample 2R-1, 8 cm, contains a single specimen of Cyclicargolithus floridanus (late Eocene to middle Miocene) along with a single specimen of the long-ranging Mesozoic species Watznaeuria barnesiae; their presence may be the result of contamination. Sample 2R-1, 13 cm, contains a single specimen each of the Cenozoic taxa C. pelagicus and Dictyococcites productus.

Four samples were taken from the Hole U1377B. Sample 330-U1377B-1R-2, 0–1 cm, contains an Eocene assemblage including Discoaster barbadiensis, Discoaster binodosus, Discoaster saipanensis, Ericsonia formosa, and Chiasmolithus grandis, which suggest a middle Eocene age. The remaining three samples were taken from Section 1R-2. Sample 1R-2, 7 cm, contains only two species that are not age diagnostic (D. productus and C. floridanus). Sample 1R-2, 28 cm, contains a mixed assemblage of late Miocene to Pleistocene nannofossils including C. macintyrei, Discoaster surculus, D. tamalis, and small Gephyrocapsa and could represent contamination. The final sample (1R-2, 29 cm) is barren of nannoflora.