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With the exception of a brief (2 m.y.) late Miocene-early Pliocene hiatus, an essentially complete Neogene record was recovered on the Kerguelen Plateau in a calcareous biofacies. The stratigraphic distribution of about 30 taxa of Neogene planktonic foraminifers recovered at Sites 747, 748,and 751 (Central and Southern Kerguelen plateaus; approximately 54°-58°S) is recorded. Faunas are characterized by low diversity and high dominance and exhibit a gradual decline in species numbers (reflecting a concomitant increase in biosiliceous forms, particularly diatoms) from about 10 in the early Miocene to 5-8 in the middle Miocene, 3-4 in the late Miocene, to essentially a lone (Neogloboquadrina pachyderma) form in the Pliocene-Pleistocene. A provisional sevenfold biostratigraphic zonation has been formulated that, together with the recovery of a representative Neogene magnetostratigraphic record, may ultimately lead to a correlation with low-latitude magnetobiostratigraphies. The initial appearance of Neogloboquadrina pachyderma is associated with magnetic polarity Chron (MPC) 4 (~7 Ma) and MPC 4A (>8 Ma) at Sites 747 and 751, respectively. INTRODUCTION Ocean Drilling Program (ODP) Leg 120 drilled five sites in a transect spanning about 4° latitude on the Central and Southern Kerguelen plateaus. The Neogene record of planktonic foraminifers is reported from Sites 747, 748, and 751 (see Fig. 1 and Table 1). With the exception of several brief hiatuses, an essentially complete Neogene section was recovered on the Kerguelen Plateau in a calcareous biofacies. Although biosiliceous elements exhibit a trend toward increasing dominance during the Neogene, planktonic foraminifers are present throughout the sequence. Faunas exhibit features typical of high-latitude cool waters: low diversity and high dominance. Fluctuating abundance patterns, particularly in the late Neogene, reflect the repeated passage of the Polar Front across this region. A provisional biostratigraphic scheme is developed for the Neogene of the Central and Southern Kerguelen plateaus, which, together with the recovery of a representative Neogene magnetostratigraphic record, may ultimately lead to a correlation with low-latitude magnetobiostratigraphies. The depths of Neogene magnetic polarity chronozones (MPC) identified in Sites 747, 748, and 751 are listed in Table 2; the stratigraphic positions of various biostratigraphic datum levels and chronostratigraphic boundaries are presented in a series of tables (3-8) that accompany site discussions. MATERIAL AND METHODS The samples discussed in this paper were collected and prepared aboard the JOIDES Resolution. Approximately one (20 cm) sample per section (less frequently, one sample every second section) plus the core-catcher (CC) sample (which was examined on the ship) were examined. Samples were prepared by washing in warm water and wet sieving over a 63 -μm screen and dried in an oven at <50°C. The faunal composition 1 Wise, S. W., Jr., Schlich, R., et al., 1992. Proc. ODP, Sci. Results, 120: College Station, TX (Ocean Drilling Program). 2 Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, U.S.A., and Department of Geology, Brown University, Providence, RI 02912, U.S.A. is reported here in semiquantitative terms based on an assessment of forms observed in a random sample of 200-400 specimens from the >63-μm size fraction. Abundances are recorded on the accompanying charts (Appendixes A-C, in back pocket) in terms of relative abundance; thus, abundant (A) = >25%, common (C) = 16%-24%), frequent (F) = 6<?o-l5%, and rare (R) = l%-5%. The generic classification used in this study follows, to a large extent, that of Loeblich and Tappan (1988). Species identifications relied heavily on Jenkins (1966, 1971), Berggren (1977), and Kennett and Srinivasan (1983). Taxonomic notes are provided to clarify concepts and usage where relevant. BIOSTRATIGRAPHY Neogene planktonic foraminifers were recovered at Sites 747, 748, and 751. Faunas are characterized by low diversity and high dominance, a characteristic feature of high-latitude, cool-water assemblages. Neogene planktonic foraminifer occurrences are presented in a series of charts (Appendixes A-C, in back pocket), and the ranges of stratigraphically useful or otherwise distinctive forms are presented in a series of range charts that accompany the text (on microfiche in back pocket). A variety of zonal schemes have been developed for the Austral midto high-latitude Neogene (see summary in Jenkins, 1975; Jenkins and Srinivasan, 1986; Berggren et al., 1983). A zonal biostratigraphy for the mid-latitude South Atlantic Neogene was formulated by Berggren (1977; see also Berggren et al., 1983). None of these zonal systems was fully applicable to the Neogene record of the Kerguelen Plateau. Elements of the Globorotalia miozea lineage figured prominently in the midto upper Neogene part of the zonal stratigraphies of these previously formulated schemes, but these forms (G. conoidea G. miotumida, G. conomiozea, G. sphericomiozea, G. puncticulata, and G. inflata) are essentially absent (or extremely rare and of sporadic occurrence only) in the Neogene of the Kerguelen Plateau. On the other hand, elements of the early part of the G. miozea group were common during the early Neogene and had a distribution similar to elsewhere in Austral and South Atlantic regions. In the mid to late Neogene, one or two taxa of globigerinids,

Neogene Planktonic Foraminifer Magnetobiostratigraphy of the Southern Kerguelen Plateau (Sites 747, 748, and 751)