20. NEOGENE BENTHIC FORAMINIFERS FROM DSDP SITES 360 AND 362, SOUTH EASTERN ATLANTIC

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1 0. NEOGENE BENTHC FORAMNFERS FROM DSDP STES 60 AND 6, SOUTH EASTERN ATANTC Alexa Cameron, Department of Geology, University of Canterbury, Christchurch, New Zealand Miocene to Quaternary benthic foraminifers have been examined from the South Atlantic Sites 60 and 6 (Figure ). Site 60 is situated midway down the continental rise off Southwest Africa, at latitude 'S, longitude 8 O'E, in a water depth of 977 meters. Site 6 is situated on the Abutment Plateau of the Frio Ridge segment of the Walvis Ridge, at latitude 9 4'S, longitude 0 'E, in a water depth of meters. The portions examined are: Site 60, Cores - (lower Pliocene-lower Miocene); Site 6, Cores -8 (Pleistocene-lower Miocene). Most of the material examined consists of foraminifer- or diatom-rich nannofossil ooze and chalks. The benthic foraminifers are sparse, and in many instances only - specimens were found for each species present (Tables and ). The benthics appear as a very small portion of the total foraminifer fauna, in most cases less than % of the sample provided. The benthic faunas are dominated by long-ranging, moderate to deep-water species, not particularly suitable for biostratigraphic subdivision. Miliolids, mainly Quinqueloculina, and Biloculina are persistent throughout Sites 60 and 6. Arenaceous forms were found with six species present at Site 60, and nine at Site 6. From the range charts (Tables and ) it can be seen that the dominant and persistent forms are: Pullenia bulloides, Pullenia quinqueloba, Oridorsalis umbonatus, Oridorsalis tenera, Cassidulina subglobosa, Cassidulina laevigata, Alabamina tenuimarginata, Sphaeroidina bulloides, Martinottiella communis, Cibicides ihungia, Cibicides molestus, Bulimina truncanella, Angulogerina esuriens, Gyroidina prominula and Gyroidinoides zelandicus. ess common, though still present, are: Hopkinsina mioindex, Euuvigerina notohispida, Bolivinafinlayi, aticarinina halophora and various species of Stilostomella. The following species observed are known from the New Zealand sequence: Cibicides molestus, Cibicides ihungia, Bulimina marginata, Cassidulina laevigata, and Pullenia bulloides. Vella (96a, b, c, 96) inferred the following depth ranges for Miocene and Pliocene forms from the east coast of the North sland, New Zealand: 0 W 0 Figure. ocation of Sites 60 and 6. Pullenia bulloides Pullenia quinqueloba Cibicides molestus Cibicides ihungia Cassidulina laevigata Bulimina marginata REFERENCES AFRCA feet feet feet feet feet feet Vella, P.P., 96a. Biostratigraphy and paleoecology of Mauriceville District, New Zealand: Trans. Roy. Soc. New Zealand Geol., v., p , 96b. Determining depths of New Zealand Tertiary seas: Tuatara, v. 0, p , 96c. ate Tertiary y Nonionid foraminifera from Wairarapa, New Zealand: Trans. Roy. Soc. New Zealand d Geol., v., p Some foraminifera from the upper Miocene and Pliocene of Wairarapa, New Zealand: Trans. Roy. Soc. New Zealand Geol., v., p

2 A. CAMERON TABE Distribution of ower Pliocene to ower Miocene Benthic Foraminifers in Site 60 DEPTH BEOW SEA FOOR N METERS 79, , 98, , 7, - 7 7, - 6, 6, ,, , 74, - 84 S4-9, 9, ,, - -,, , 60-69, 79-88, 98-07, 7-6, 6-4, - 64, 74-8, EG 40 STE 60 O u Z O u 4 E < al z Cibicides sp. Mαrtinottiellα communis Gyroidinα zelαndicus ßuliminα miolαevis Cαssidulinα subglobosα Brizαlinα sp. Pulleniα bulloides Anomαlinoides fαsciαtus Oridorsαlis umbonαtus Stilostomellα bαsicαrinαtα Angulogerinα esuriens D : E o c c O o E Ë g l> O D < l_ <, Kαrreriellα/Siphote tulαriα [ ], l Sphαeroidinα bulloides Euuvigerinα notohispidα Rosαlinα sp. Stilostomellα stαchei Stilostomellα 'bortonicα' Cibicides (with umbonαl plug) Bolivinα sp. Cibicides (flanged) l j r r a Cassidulina laevigata Globobulimina sp. Quinqueloculina sp. Alabamina tenuimarginata Karrerulina aegra Cibicides novozealandica aticarinina halophora \ Nodosaria longiscata Nodosaria sp. Anomalina aotea Bulimina truncanella Massilina tenuis. 8

3 NEOGENE BENTHC FORAMNFERS TABE - Continued Nuttαlides truempyi { σ "o ç b E σ c 'Ë z> Bolivinopsis cubensis Melonis zeobesus Nodosαriα obliquecostαtα Cibicides robertsoniαnus Sigmoilopsis schlumbergeri Stilostomellα verneuilli Stilostomellα pomuligerα Quinqueloculinα sp. Nodosαrellα subnodos αgenonodosαriα hirstuα Nodosαriα delicαtulα i Nodosαriα striαtα Uvigerinα sp. Vαginulinα vagina Uvigerina plejeba Vulvulina sp. Uvigerina striata Bulimina pupula Proxifrons sp. Ehrenbergina sp. AUSTRA-NEW ZEAAND PANKTONC FORAMNFERA ZONES (Jenkins 966, 967, 97) puncticulara conomiozea miotumida mayeri mayeri TROPCA PANKTONC FORAMNFERA ZONES (Bolli 97, 966, 97) margaritae Neogloboquadrina dutertrei acostaensis menardii mayeri Globigerinoides ruber fohsi robusta fohsi lobata fohsi fohsi U M AGE POCENE MOCENE Orbulina suturalis fohsi peripheroronda Praeorbulina glomerosa curva Praeorbulina glomerosa Globigerinoides trilobus trilobus Globigerina woodi connecta Globigerinatella insueta Globigerinita stainforthi Globigerinita dissimilis 8

4 A. CAMERON TABE Distribution of Pleistocene to ower Miocene Benthic Foraminifers at Site 6 EG 40 STE 6 TTXΠT _o i s * s o S * o t S " J.8 o j?! f! j j }}i U!!?{] 4!f. Jl; i. i i * s s s!! s J J g % j j j! J. j 6-4, , T , ~~ 8-60 * Ė_= T _~ T : :Z: TZZZTZZZ" ZZZZZZZZ_ZZZZZ T ZZZZ 74 -» -J 9- l T Zt _ T T 8, J_ 9-0, 7 cc j Z ZZTZZZ_" ZZZZ ZTT 0,- _8 -, , , ~T~ 8-60 ~ t T T~f T ee ZT Z Z TZZ Z ZZZ ZZZZ TZ ZTZ±Z ZZZZ 40,- 0 U _^ 0-9, 8-60 [ f 97, ,- 6 7 T" 8-60,- 4 8 T f^óë~ 4,- 64 J Süziiz! EE HE; feijii J^ETTFETF ;EÉEE ~:ME 9, ,- ~CX J 0,- 40 _ , ~68,- 7Jr~"~~~ 8-60 " j~~ El " 87, ~~ 8-60 "j _ 406, U 4,- 4 8 ~~ 8-60 ^ir_±±^z ± zz :: :- :l: Zi:zzz :: ZEzzzla: : zzzllzzz : zzrz =±^i-^ei=; ii=-?i^~-i! = EËZ - -= =i== 48,- 49 ] 8-60 T" 8-60 ec-t" " ~ Z Z_ZZTZZ±Z±ZZZZZ±±t±ZZ~±7ZZZtzZ±Z 0, C^X T -. Z tt^ T_ T _ 0, J 8-60 T ZZÜE^^ z^z±i zizzzt^zii ~Tz~izziziiz±±irriiz~i~izπ: ÜWÜ çç_ T TT T T T T fi 77,- 87 _ J_ J β ^. T ZZ +l 8-60 TT z:zez: :z: tzrz~ ;Z±ZJZ~±ZZZZZZT_T^T; ~±Z±ZZZ 96, a - z" :tzi_t: J T: " T t T T T; lit 6, Zz^Z ~Tr T TT : ZZZZZZZZZZZZZZZZZZZZ 644-6,

5 NEOGENE BENTHC FORAMNFERS TABE - Continued Stilostomellα verneuilli Angulogerinα esuriens Globobuliminα (arenaceous) Dental ino subcostata Proxifrons sp. Ellipsoglandulina subconica Vaginulinopsis sp. c Bol vina anostomosa 'i Cerobertina sp. Nodosaria Mspida Astrononion impressum, Buliminella sp., Nodosaria p/rula ßulimina pupulσ i Textularia sp. Hofkeruva zeocuminata oxostomum sp. i U. Cerobertina flong, thin) Quadrimorphiπo sp. Astrononion charlottensis l AUSTRA-NEW ZEAAND PANKTONC FORAMNFERA ZONES (Jenkins 966, 967, 97) truncatulinoides inflata puncticulata conomiozea TROPCA PANKTONC FORAMNFERA ZONES (Bolli 97, 966, 97) trunc.truncatulinoides or truncatulinoides truncatulinoides truncatulinoides cf - tosaensis miocenica GloborotaEia margσritae Neogloboquodrina dutertrei acostaensis M U AGE PESTOCENE PESTOCENE UPPER POCENE POCENE menordii mayeri - fohsi robusta M MOCENE mayeri mayeri fohsi lobata Orbulina suturalis fohsi fohsi fohsi peripheroronda Praeorbulina glomerosσ curva Praeorbulina glomerosa curva Globigerinoides trilobus trilobus Globigerinatella insueta "GlθDTgèrinrtà~stain?orTrTi~'- GlobiQcriπitö dissirni is 8

6 A. CAMERON Figure PATE Bolivinopsis cubensis (Cushman and Bermudez). 4. Sample 6-9,. conomiozea Figure Massilina tenuis (Czjzek). 47. Sample 6-9,. conomiozea Figure Vaginulina vagina (Stache).. Sample 6-9,. conomiozea Figure 4 Vaginulinopsis spinulosa (Stache). 6. Sample 60-,. Globigerinoides trilobus trilobus Zone; lower Pliocene. Figures, 6 Plectofrondicularia whaingaroica (Stache). 9. Sample 6-,. puncticulata Zone; lower Pliocene. Figure 7 Stilostomella basicarinata Hornibrook. 9. Sample 6-4,. puncticulata Zone; lower Pliocene. FigureS Stilostomella pomuligera (Stache). 9. Sample 6-8,. inßata Zone; middle Pliocene. Figure 9 Stilostomella stachei (Chapman). 9. Sample 6-0,. conomiozea Figure 0 Bulimina truncanella Finlay. 70. Sample 6-0,. conomiozea Figure Angulogerina esuriens Hornibrook. 99. Sample 6-7-4, 8-60 cm. puncticulata Figure Cassidulina subglobosa Brady. 68. Sample 6-0,. conomiozea Figures, 4 Pullenia bulloides (d'orbigny). 9. Sample 6-8,. inflata Zone; middle Pliocene. Figures, 6 Pullenia quinqueloba (Reuss). 9. Sample 6-4,. inflata Zone; Pleistocene to upper Pliocene. Figure 7 Alabamina tenuimarginata (Chapman, Parr and Collins). 9. Sample 6-0,. conomiozea Figures 8-0 Gyroidina zelandicus (Finlay). 9. Sample 6-9,. conomiozea Figures - Anomalina aotea Finlay. 0. Sample 6-0,. conomiozea Figures 4, Anomalinoides fasciatus (Stache). 47. Sample 6-8,. inflata Zone; middle Pliocene. 86

7 NEOGENE BENTHC FORAMNFERS PATE 87