Exon, N.F., Kennett, J.P., and Malone, M.J. (Eds.)Proceedings of the Ocean Drilling Program, Scientific Results Volume 189
10. LATE CRETACEOUSQUATERNARY BIOMAGNETOSTRATIGRAPHY OF ODP SITES 1168, 1170, 1171, AND 1172, TASMANIAN GATEWAY1
C.E. Stickley,2 H. Brinkhuis,3 K.L. McGonigal,4 G.C.H. Chaproniere,5 M. Fuller,6 D.C. Kelly,7 D. Nrnberg,8 H.A. Pfuhl,9 S.A. Schellenberg,10 J. Schoenfeld,8 N. Suzuki,11 Y. Touchard,12 W. Wei,13 G.L. Williams,14 J. Lara,4 and S.A. Stant4
Late Cretaceous (Maastrichtian)Quaternary summary biostratigra-phies are presented for Ocean Drilling Program (ODP) Leg 189 Sites1168 (West Tasmanian Margin), 1170 and 1171 (South Tasman Rise),and 1172 (East Tasman Plateau). The age models are calibrated to mag-netostratigraphy and integrate both calcareous (planktonic foraminifersand nannofossils) and siliceous (diatoms and radiolarians) microfossilgroups with organic walled microfossils (organic walled dinoflagellatecysts, or dinocysts). We also incorporate benthic oxygen isotope stratig-raphies into the upper Quaternary parts of the age models for furthercontrol. The purpose of this paper is to provide a summary age-depthmodel for all deep-penetrating sites of Leg 189 incorporating updatedshipboard biostratigraphic data with new information obtained duringthe 3 yr since the cruise. In this respect we provide a report of work toNovember 2003, not a final synthesis of the biomagnetostratigraphy ofLeg 189, yet we present the most complete integrated age model forthese sites at this time.
Detailed information of the stratigraphy of individual fossil groups,paleomagnetism, and isotope data are presented elsewhere. Ongoing ef-forts aim toward further integration of age information for Leg 189 sites
1Stickley, C.E., Brinkhuis, H., McGoni-gal, K.L., Chaproniere, G.C.H., Fuller, M., Kelly, D.C., Nrnberg, D., Pfuhl, H.A., Schellenberg, S.A., Schoenfeld, J., Suzuki, N., Touchard, Y., Wei, W., Wil-liams, G.L., Lara, J., and Stant, S.A., 2004. Late CretaceousQuaternary biomagnetostratigraphy of ODP Sites 1168, 1170, 1171, and 1172, Tasma-nian Gateway. In Exon, N.F., Kennett, J.P., and Malone, M.J. (Eds.), Proc. ODP, Sci. Results, 189, 157 [Online]. Available from World Wide Web: . [Cited YYYY-MM-DD]2Lamont-Doherty Earth Observatory, Palisades NY 10964, USA. Current address: School of Earth, Ocean and Planetary Sciences, PO Box 914, Cardiff University, Cardiff, CF10 3YE, United Kingdom. firstname.lastname@example.orgBotanical Palaeoecology, Laboratory of Palaeobotany and Palynology, Utre-cht University, CD-3584 Utrecht, The Netherlands.4Department of Geological Sciences, Florida State University, Tallahassee FL 32306, USA.5Department of Geology, The Austra-lian National University, Canberra ACT 0200, Australia.6Hawaii Institute of Geophysics and Planetology, University of Hawaii at Manoa, Honolulu HI 96822, USA.7Department of Geology and Geo-physics, University of WisconsinMadison, Madison WI 53706, USA.8GEOMAR Research Center for Marine Geosciences, D-24148 Kiel, Germany.9Max Planck Institute for Biogeochem-istry, 07745 Jena, Germany.10Department of Geological Sciences, San Diego State University, San Diego CA 92182, USA.11Institute of Geology and Paleontol-ogy, Tohoku University, Sendai 980-8578, Japan.12CEREGE, Europle Mditerranen de lArbois BP80, F-13545 Aix en Provence Cedex 4, France.13Scripps Institution of Oceanography, University of California, San Diego, La Jolla CA 92093, USA.14Geological Survey of Canada (Atlan-tic), Bedford Institute of Oceanogra-phy, Dartmouth NS B2Y 4A2, Canada.
Initial receipt: 28 February 2003Acceptance: 22 March 2004Web publication: 13 August 2004Ms 189SR-111
C.E. STICKLEY ET AL.LATE CRETACEOUS-QUATERNARY BIOMAGNETOSTRATIGRAPHY 2
and will include an attempt to correlate zonation schemes for all themajor microfossil groups and detailed correlation between all sites.
Five sites (Sites 11681172) were drilled in water depths of 24633568 m during Ocean Drilling Program (ODP) Leg 189 in the Tasma-nian Gateway in MarchMay 2000 (Fig. F1). In all, 4539 m of Late Cre-taceous to Quaternary marine sediments were recovered, with an over-all recovery of 89%. The sediments of Leg 189 essentially record theAntarctic Cenozoic evolution from Greenhouse to Icehouse (seeExon, Kennett, Malone, et al., 2001). Postcruise work is presented inthis volume and notably in Exon et al. (in press). The biomagnetostrati-graphic age models for the four deep sites (Sites 1168, 1170, 1171, and1172) are presented in this paper. Difficulties in drilling at Site 1169 re-sulted in a high amount of core disturbance, causing unreliable age as-signment. Drilling was aborted beyond one advanced piston corer/ex-tended core barrel (APC/XCB) hole, and no further postcruise attempthas been made to refine the shipboard age model (Shipboard ScientificParty, 2001c) for this site.
The relatively shallow region off Tasmania is one of the few placeswhere well-preserved and almost complete marine Cenozoic carbonate-rich sequences can be drilled in present-day latitudes of 4050S andpaleolatitudes of up to 70S. The broad geological history of all the sitesis comparable, although important differences exist east to west andnorth to south (e.g., Exon, Kennett, Malone, et al., 2001; Brinkhuis,Munstermann, et al., this volume; Brinkhuis, Sengers, et al., this vol-ume; Huber et al., submitted [N1]; McGonigal, in press; Pfuhl et al., inpress; Pfuhl and McCave, this volume; Stant et al., this volume; Stick-ley et al., submitted [N2]). The wide range of lithologies recovered dur-ing Leg 189 (Exon, Kennett, Malone, et al., 2001) are almost completelyfossiliferous throughout the Cretaceous to Quaternary; they contain awealth and diversity of microfossils (e.g., diatoms, nannofossils, ostra-codes, planktonic and benthic foraminifers, radiolarians, and silicoflag-ellates) and palynomorphs (dinocysts, acritarchs, spores, and pollen) invarying abundances and associations, providing ample opportunity todevelop correlations between groups. The main groups are used here toderive age models for the four deep-penetrating sites. These are themost complete integrated biomagnetostratigraphic data for Leg 189 toMarch 2003. This is not intended as a final synthesis, however, and on-going work on individual fossil groups is still refining some intervals.
Microfossil Groups at Leg 189 Sites and Their Application to the Age Models
Five microfossil groups of age significance are present in Leg 189 sed-iments in varying abundances. These comprise a calcareous grouping(nannofossils and planktonic foraminifers), a siliceous grouping (dia-toms and radiolarians), and palynomorphs (notably organic walled di-noflagellate cysts or dinocysts, spores, and pollen). Other groups (e.g.,benthic foraminifers, ostracodes, silicoflagellates, and ebridians) arepresent in varying abundance through selected stratigraphic intervals(see Exon, Kennett, Malone, et al., 2001) but are not used here for ageassignment.
142E 146 148144 150
Site Site 11681168Site 1168
Site 1172Site 1172Site 1172100010001000 2
Site 1171Site 1171Site 1171
Site 1170Site 1170Site 1170Site 1169Site 1169Site 1169
South Tasman Rise
F1. Leg 189 drill sites, p. 26.
C.E. STICKLEY ET AL.LATE CRETACEOUS-QUATERNARY BIOMAGNETOSTRATIGRAPHY 3
The stratigraphic distribution of the main microfossil groups throughthe drilled sequences changes markedly with depositional environ-ment/lithology. The calcareous groups are most abundant in the pelagiccalcareous oozes of the OligoceneQuaternary (Stant et al., this vol-ume; McGonigal and Wei, this volume; McGonigal, in press; Wei etal., this volume), whereas palynomorphs are the dominant group inthe shallow-water siliciclastic sediments of the Maastrichtian and Paleo-gene (Brinkhuis, Munstermann, et al., this volume; Brinkhuis, Sen-gers, et al., this volume). However, palynomorphs and calcareousgroups are largely abundant throughout the drilled sequences at Site1168. In addition, well-preserved dinocysts are present in the Quater-nary intervals of Sites 11681172, making these occurrences the south-ernmost Quaternary dinocysts records to date. Diatoms are commonlyabundant in sediments of late Eocene age and younger at all sites (ex-cept Site 1168), with pyritized specimens frequently occurring in theMaastrichtianmiddle Eocene intervals. Radiolarians are abundant atSite 1171 from the upper Eocene and at Site 1170 from the Oligocene.At Site 1172 they are common only in the Eocene and Miocene inter-vals. At Site 1168 diatoms and radiolarians are preserved only in twoshort intervals in the mid-Oligocene and upper Miocene, and thereforeare not useful for age assignment at this site. Benthic foraminifers arepresent throughout the drilled intervals of all sites except for the upperEocene glauconitic sands. They give an indication of paleobathymetrichistory through the sequences (see Exon, Kennett, Malone, et al., 2001).
Extensive postcruise high-resolution calcareous nannofossil strati-graphic work has been undertaken through the Neogene