Hole 1090B is located in the central part of the Subantarctic Zone on the southern flank of the Agulhas Ridge (42°54'S, 8°53'E). Hole 1090B was drilled to 397.5 meters below seafloor (mbsf), and Holocene to middle Eocene sediments were recovered. Core recovery of the Eocene to lower Oligocene interval was generally good, even though sediments were recovered by the extended core barrel (XCB) system (Shipboard Scientific Party, 1999). Because the paleomagnetic signal and nannofossil assemblages are well documented in this interval, Hole 1090B may represent a reference record to improve knowledge of the Eocene-Oligocene transition (Shipboard Scientific Party, 1999, doi:10.2973/odp.proc.ir.177.105.1999).We analyzed the calcareous nannofossil assemblages of the middle Eocene to lower Oligocene interval, focusing especially on the Eocene-Oligocene transition, with quantitative investigations of nannofossil assemblages.

Six calcareous nannofossil abundance levels were recorded, as follows: VA = very abundant (>50 specimens per field of view).A = abundant (11-50 specimens per field of view).C = common (1-10 specimens per field of view).F = few (0.1 to <1 specimens per field of view).R = rare (0.02 to <0.1 specimens per field of view).RR = very rare (<0.02 specimens per field of view).Preservation of nannofossils was recorded as good (G), moderate (M), poor (P), and very poor (VP). Some samples were barren (B) of calcareous nannofossils. Reworking phenomena were noted in some Eocene intervals.

Supplement to: Marino, Maria; Flores, José-Abel (2002): Data Report: Calcareous nannofossil data from the Eocene to Oligocene, Leg 177, Hole 1090B. In: Gersonde, R; Hodell, DA; Blum, P (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 177, 1-9