The distribution of radiolarian assemblages in the modern and ice-age Pacific

The distribution of radiolarian assemblages in the modern and ice-age Pacific

Marine Micropoleontology , 3(1978): 229--266 © Elsevier Scientific Publishing Company, Amsterdam -- Printed in The Netherlands 229 THE DISTRIBUTION ...

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Marine Micropoleontology , 3(1978): 229--266 © Elsevier Scientific Publishing Company, Amsterdam -- Printed in The Netherlands

229

THE DISTRIBUTION OF RADIOLARIAN ASSEMBLAGES IN THE MODERN AND ICE-AGE PACIFIC

T.C. MOORE, JR.

Graduate School o f Oceanography, Kingston, R. L 02881 (U.S.A.) (Approved for publication March 22, 1978)

Abstract Moore, Jr., T.C., 1978. The distribution of radiolarian assemblages in the modern and ice-age Pacific. Mar. Micropaleontol., 3: 229--266. Data on radiolarian abundances from several recent regional studies of the Pacific have been combined with new data from the temperate and tropical area to provide an ocean-wide view of radiolarian distributions. A Q-mode factor analysis of these data identified seven factors which have their areas of dominance in the following regions: tropics, western Pacific, subarctic, Antarctic, transitional zone, temperate regions, and the eastern central water masses. The distributions of these factors tended to follow those of surface water masses and major ocean currents. A more detailed analysis of the temperate and tropical region better delineated the complex flow and counter flow in this area. The relationship between the distribution of modern radiolarian assemblages and the surface circulation of the Pacific can be used to deduce the nature of oceanographic changes which occurred in the past. The modern radiolarian distributions are compared with those mapped at the 18,000 B.P. level and reveal two major differences in the ice-age Pacific. The Tropical Factor, restricted primarily to the eastern half of the ocean in modern times, ranged across the entire ocean at 18,000 B.P. and extended into the area of the western boundary currents. The Subarctic Factor, now found mainly in the western subarctic, expanded to the east and south at 18,000 B.P. and had strong similarities to an assemblage found in the subantarctic area. The expansion of these two dominant assemblages was at the expense of the Western Pacific, Temperate, and Transitional Factors. These differences in the 18,000 B.P. distributions are thought to be caused by an increase in the influence of arctic air masses in the North Pacific and by a general increase in the wind-driven zonal flow.

Introduction The plankton of the oceans have distributions which generally match the patterns of the surface water masses (e.g. Bradshaw, 1959; B~ and Tolderlund, 1971; McGowan, 1971; Okada and Honjo, 1973). Furthermore, ~he microfossils derived from these planktonic organisms have distributions on the ~sea,~ floor which represent a long-term aver:age of those found in overlying waters (e.g. McIntyre and B~, 1967; Petrushevskaya, 1971a, b; Hutson et al., 1972; McMillen,

1976; Hutson, 1977). Thus, if effects of dissolution and the bioturbation of sediments are taken into account, microfossfls in the surface sediments of the sea floor can be related to surface water masses, and by studying d o w n , o r e changes in these microfossfls assemblages, past changes in the distribution of these water masses can be deduced (e.g. Geitzenauer et al., 1976; Kipp, 1976; Sancetta, 1978). Two microfossil groups of the zooplankton, foraminifera and Radiolaria, are commonly used in quantitative studies aimed at learning more about p u t

230 oceanographic conditions. In such studies, Radiolaria may offer two advantages over the foraminifera. First, the resistance of their opaline tests to dissolution make them particularly useful in productive near-shore areas, in the polar regions, and in the deepocean areas where carbonate dissolution is high. Thus, for microfossil studies in the Pacific Ocean, the most comprehensive coverage of the main water masses is achieved with the Radiolaria. Second, the Radiolaria are much more diverse than the planktonic foraminifera. In high latitudes, where the foraminiferal assemblage is strongly dominated by one species, there may be as many as twelve radiolarian species present in more than trace numbers (i.e. >2% of the population). In the tropics there are well over 100 species present in the surface sediments. If variation in the relative proportions of microfossil species is to be used in down-core studies as a paleoceanographic "barometer", the effect of this greater diversity is to provide a more finely divided scale against which to measure changes in oceanographic conditions, a scale which doe~ not "bottom out" under the extreme, near-polar conditions. Compared to the many studies of the calcareous microfossils, studies relating the distribution of living polycistine Radiolaria to that of their fossil forms on the deep-sea floor are rare (e.g. Petrushevskaya, 1971a, b; Renz, 1973; McMillen, 1976). There are, however, indications that the distributions of both living and fossil forms can be related to current systems and surface water masses. In the past few decades studies of the distribution of radiolarian microfossils (e.g. Nigrini, 1970; Casey 1971a, b; Petrushevskaya, 1971a, b) have shown that the distribution limits of many species closely follows water mass boundaries. Based on such findings Radiolaria have been used to estimate the timing and relative magnitude of oceanographic changes during the Pleistocene using both qualitative (Casey, 1971b) and semiquantitative techniques (Nigrini, 1970). In more recent years, the quantitative techniques

developed by Imbrie and Kipp (1971), and first used on foraminifera, have been applied to radiolarian assemblages (Moore, 1973a; Sachs, 1973, 1975; Robertson, 1975; Hays et al., 1976; Lozano and Hays, 1976; MolinaCruz, 1977a; Dow, 1978). In this study, much of the published data from mid- to high-latitude areas of the Pacific Ocean have been combined with new data from the temperate and tropical regions. Together, they give a nearly complete coverage of radiolarian distributions in surface sediments of the Pacific ranging from the Bering Sea to the Antarctic. Based on the relative abundances of radiolarian species in these samples and on their relationship to m o d e m surface water masses, it is possible to interpret past changes in radiolarian distributions in terms of ocean-wide changes in circulation. Methods

Sample preparation Surface sediment samples were treated with dilute hydrochloric acid and hydrogen peroxide in order to disaggregate the sediment and to remove carbonate material. The sampies were sieved at 63 /~m and the coarse fraction retained. If, after treatment, the radiol~xian tests in this fraction were partially obscured or encased by an amorphous coating of silica and clay, the coarse fraction was treated for 10 to 30 s with a concentrated solution of sodium hydroxide, lightly agitated in an ultrasonic bath, and then resieved. This treatment usually broke up such coatings with little or no damage to the tests. The coarse residue was mounted in balsam on glass slides following the technique described by Moore (1973b). This procedure produces a random distribution of tests on the slide and allows a representative count of species to be made from only part of the mounted sample. For most samples, 400--800 specimens were identified and counted. In addition to the samples examined especially for this study, data were also

231

derived from regional studies carried out by Robertson (1975), Molina-Cruz (1977a), and Dow (1978) (Appendix I). The preparation and counting techniques used by these investigators were similar to those described above.

Taxonomy The taxonomy in this and the above-mentioned studies (Tables I, II) generally follows those notes and illustrations presented by Dow (1978) and by Molina-Cruz and Moore (in Molina-Cruz, 1977a). The taxonomy of Radiolaria has been undergoing rapid changes in recent years, and at the time of the early quantitative studies of Radiolaria, it did not allow a comprehensive and consistent division of modern species. As a result, some investigators (Moore, 1973a; Sachs, 1973; Robertson, 1975) used several polygeneric and generic counting groups to describe the assemblages. For regional studies of radiolarian assemblages carried out by a single investigator, such an approach is entirely adequate. In such studies these subjectively defined counting groups maintain a coherency which is insured partially by the limited geographic range of the study and partially by the fact that one person has both defined the counting grOUl,~S and produced the counts. Such an approach is not particularly helpful, however, when other investigators try to incorporate ~hese data in a broader study. When uncertainties developed concerning the definition of counting groups used in previous studies, either the original samples were recounted (e.g. those of Moore, 1973a) or the counting groups in question were eliminated from the total data set (e.g. Cenosphaera sp. of Robertson, 1975).

Species selection Because of the relatively high diversity of Radiolvria, selectivity can be exercized in choosing the species to be studied. Some of these choices, are forced upon us by the

state of the taxonomy and by the methods used in defining the assemblages. For this investigation, the species used were limited to those whose definitions were clearly agreed upon by the workers whose data were incorporated in the study. Some species are much more commonly found in one hemisphere than the others (e.g. Lithelius nautiloides). Such species often were included in the counting groups employed in one regional study, but not in a similar study from the opposite hemisphere. These mismatches in counting groups preclude the use of such species in this study and results in the amalgamated data set being dominated by bipolar and cosmopolitan forms. Only species which are clearly restricted to one hemisphere (e.g. Antarctissa strelkovi) are exceptions to this general rule. The relative abundance of a species places a further limit on its usefulness. In this and in the previous quantitative studies of Pacific Radiolaria, the species were grouped using a Q-mode factor analysis (Klovan and Imbrie, 1971; see below). The grouping of these species and their importance in defining each of the factors (or assemblages), depends on their relative abundance in the samples. Species which are never present in proportions greater than 2% of the population have very little effect on the mathematical definition of the assemblages. Furthermore, it is difficult to accurately determine the exact abundance of these rarer species without examining a very large number of specimens, and in some c~es the counting error involved in determining their abundance obscures any distributional "signal" they might provide. Therefore, rare species (i.e. those forming less than 2% of the population) are not considered in this study. In the data spanning the entire Pacific there are 28 radiolarian species which meet these criteria (Table I). By limiting the data set to the temperate and tropical regions of the Pacific (i.e. incorporating only the new data and that of Molina-Cruz, 1977a), 44 species could be found which met the

TABLE I

0.096 0.U0 0.449 0.132 0.143

-0. 9 -0.27 0.I0 -0.24 -0.07

4.849 -0.137

0.66 -0.84

--0.095 0.333 0.134 -0.187

1.116 0.092 -0.015 0.024 -0.128

0.27 0.12 --O.31 --0.16 -0.40

-0.75 0.35 --0.15 -0.42

0.508 0.146 0.140 0.120 1.525

0.36 0.39 0.10 -0.27 0.61

A. strelkovi Petrushevskaya, 1967 Carpocan/um spp. Nigrini, 1970 L.~.ospyr/s ret/cu/ata (Ehrenberg) 1872 8iphocampe aquilonaris (Bailey) 1856 Theocalyptra bicornis (Popofsky) 1908 T. bicornis var. (Hays) 1965 T. dac~,ana (Ehrenberg) 1861 7'. davbiana vat. comutoides (Petrnshevskaya) 1967 Theoconus minythorax Nigrini, 1968 7". zancleus (Muller) 1858 Theocorythium trachelium (Ehrenberg) 1872

-0.836 -0.041 -0.021 1.046 0.187 --0.006

-0.194 --0.151 -0.039 0.197 0.084 -0.026

-0.44 -0.43 -0.39 0.30 0.20 -0.16

--0.413 -0.807 -0.308 0.308

0.518

0.141 0.639 -0.040 1.272

--1.618 0.221

0.835 0.637 0.034 0.271 0.447

1.150 0.532 0.341 -0.460 4.098

-0.295

--0.137

-0.02

W. Pac.

Acfinomma antarct[cum (Ha~ckel) 1887 A. arcadophorum Haeckel, 1887 A. med/anum spp. NiMini, 1970 A. leptodermum (Jorgenscn) 1900 Cenosphaera erbtata Haeckel, 1887 Dictyocorne profunda Ehrenberg, 1860 D. truncatum (Ehrenberg) 1861 Echinomma of. leptodermum Jorgensen, 1905 Euchitonia elegans (Ehrenberg) 1872 E. furcata Ehrenberg, 1872 E. triangulum (F,hrenberg) 1872 Ilymenastrum euclidis Haeckel, 1887 Lithelius minor Jorgensen, 1899 Ommartartus tetrathalamus (Hacckel) 1887 Ommatodiscus 81). A & B (Benson) 1966 Stylochlamidium asteriscus Haeckel, 1887 Polysolenia lappaceo (Haeckel) 1887 Prunopyle antarctica Dreyer, 1889 8pirerna melonia Haeckel, 1887 Sty lodictya validispina Jorgensen, 1905 Tetrapyle octacantha Muller, 1858 Octopyle stenozoa Haeckel, 1887 Antarctiua denticulata (Ehrenberg) 1894

Trop.

Cornel. coeff.

Pen-Pacific species

4.962 0.203 -0.314 --0.067

0.083

-0.092 -0.001 0.008 1.104

-0.133 -0.154

0.257 --0.005 0.013 0.032 1.025

0.010 0.011 -0.005 0.690 -0.079

-0.494 0.137 -0.272 -0.002 0.004 -0.023

-0.4~19

8uberc.

--0.508 -0.184 2.627 0.051

1.678

"-0.147 0.325 -0.037 2.804

0.351 -0.~,42

-0.704 -0.113 0.367 0.796 0.432

-0.149 -0.057 0.048 1.304 -0.262

1.570 1..022 1.537 --0.026 -0.030 0.845

-0.001

Trans.

0.229 0.006 -0.089 --0.009

0.274

3.160 -0.059 0.001 -0.064

0.225 4.113

0.125 -0.024 --0.008 0.027 0.066

-0.008 -0.014 0.002 0.088 -0.100

0.504 0.359 0.117 0.034 --0.006 0.047

0.683

Antare.

--0.942 0.253 --1.876 0.084

-0.524

0.062 0.018 0.087 0.178

0.116 0.105

--1.240 0.179 --0.001 0.374 0.623

--0.005 -0.086 0.038 4.457 0.284

-0.917 -0.208 -0.310 -0.059 --0.028 --0.231

-0.182

E. Cent.

-0.298 -0.254 0.024 0.292

-0.365

-0.248 -0.100 -0.088 -0.695

-0.775 -0.290

4.473 0.082 --0.076 0.105 0.651

0.039 -0.021 -0.040 1.530 --0.560

1.470 0.790 0.032 -0.084 -0.018 --0.026

0.688

Temp.

#4, Dow, 1978

#24, Dow, 1978

Sp.

Sp. #$54, Molina4~ruz, 1977a Sp. #2, Dow, 1978 Petrmlhenkays, 1967, fig. 50 II, IV Sp. #1, Dow, 1978 Sp. #20, Dow, 1978 8p. #N1, Molina-Cruz, 1977a Sp. #40, Dow: 1978 8p. #N38, Molina-Cruz, 1977a Sachs, 1973,131.2.60 Sp. #19, Dow, 1978 8acbe, 1973, pl.2.6b 8p. #N7, Molina-Cmz, 1977a 81). #34, Dow, 1978 8p. #N42, Molina-Cmz, 1977a

Bemmn, 1966,1)1.10.4 811. #10 a 21, Dow, 1978 NiMini, 1970, pl.l.a Sp. #88, Molina-C~mz,1977a Sp. #16, Dow, 1978 81). #11, Dow, 1978

#812, Molina-Cruz, 1977a #836C, Molina-Cruz, 1977a #S18, M ~ . ~ , 1977a #13, Dow, 1978

811. 8p. Sp. Sp.

81). #83, Mo!,_'ns-Cruz, 1977a 8p. #6, Dow, 1978 811. #85, Molina-Cruz, 1977a 8p. #836A, Molina-Cruz, 1977a Benson, 1966, pl,15.X 81). #87, Molina-CYuz, 1977a

8p.

Species description

The 28 species end species groups used in the analysis of the Pan-Pacific data set; the relative importance (scaled factor scores) of emrb species in defining the seven factors is given along with the correlation between relative species sbundance and August sea-surface temperature; recent references to descriptions and illustrations of the species are given in the right-hand column

t@ Qo b~

Thobm~m sceph/pe. (HMckd) 1887

Petmshemdu~va, 1967 A. dent/cubnta tar. cylindrica Petrushevskaya, 1967 A. stre/kovi Petrushevskaya, 1967 Anthocyrtidium ophirense (Ehrenheqg) 1872 C4~ocm/um spp. NiMini, 1970 G~r/s anSubshs (l-18eekei)1887 Lirioq~ris mticulata (Ehrenberg) 1872 /qeroean/um komtnevi (Doffiel) 1952 P. prwtextum eucolpum Haeckel, 1887 P. pnm~sxfum pmetextum (Ehrenbers) 1872 Pteroeorys h/rondo Haeckel, 1887 S/phocompe oqu//ommb (Bailey) 1856 Theoc~ypfra b/com/s (Popofsky) 1908 T. b/com/s vat. (Hays) 1965 T. drab/row (Bhrenbers) 1861 T. d ~ / i m z var. comuto/des (Petmsheulkqa) 1967 TAeocorms m/aythorax NiMlni, 1968 T. z ~ e / e u (Muller) 1858 77reocoryth~m tracl~lium (Bhrenberlg) 1872

Anturetism denticulata vat.

Lmeosp/ra quadranp/a Haeckei, 1887 Litheliu m/nor Joqgenmm, 1899 Octopy/e 8tenozoa Haeckel, 1887 Tetrapy/e oehwantha Muller, 1858 Ommafortm tetrathaJbmw (14j.w.kel)1887 /'o~soleaia lapin'ca (Haeckel) 1887 P. sp/noso (Haeckel) 1860 Prunopy/e antaret/ca Dreyer, 1889 8pirema me/on/a Haeckel, 1887 8ponsseter tetras Ehrenbers, 1860 8pon4mms (?) sp. Petrushevsksya, 1968 Spon4ums cf. effiptica (k'~renberg) 1872 StylocMmnidham asteriscu Haeckel, 1887 8. aster/scw vat. Haeckel, 1887 S~kM/etya uaUdisp/na Jorsensen, 1905

Hyme~stmm euclidis Huckel, 1887

Hezapyle 81~p.Huckel. 1881

,g. trknaufum (Mttmnberg) 1872 Heliodiscm mteriscus Haeckel, 1887

A c f f n o m m areadophomm Haeekel, 1887 A. med/mmm NiMini, 1967 A. feptodermum (Jorgenseu) 1900 Cenospkaera cr/sbsta Hseckel, 1887 D/ctyocome profunda Ehrenberg, 1860 D. blncatum (Bhrenberg) 1861 geh/nomma el. leplodermum J m ~ m e n , 1905 £,chitom~ e/qNns (Eimmbers) 1872 R. ~rceto l ~ m t M ~ , 1872

Temperate-Tropical 0peci~

-0.007 -0.015 0.107 0.770 0.788 -0.003 0.011 0.047 -0.045 0.018 0.042 0.237 -0.372 0.043 -0.637 0.015 0.470 -0.038

---0.000 -0.001 0.212 0.113 0.458 0.213' 0.012 0.334 0.029 --0.235 -0.154 0.235 -0.025 0.877 0.147 0.054 0.165

0.066

-0.009

-0.003 3.103 0.017 -0.446 1.257

--0.341 0.187 0.255 -0.200 0.419 4.676

-0.015 ~--0.038 0.006 -0.496 -0.454 0.302 -0.142

-0.013

-0.417 0.312 -0.096 0.188 0.213 -0.631 -0.232 1.807 -0.187 1.002 0.325 -0.232

0.854 4.831 0.687 1.654 -0.009 0.177 1.313 -0.279 0.486 2.762 0.023 1.313

6.357 -0.156 -0.266 -0.709 -0.074 -0.142 -0.297 0.274 -0.103 -0.771 0.294 -0.167

0.001

1.296 0.269 --1.161 -0.781 0.039 -0.183 --0.174

1.544 0.622 0.757 0.089 0.358 --0.004 --0.003

-0.067 -0.109 0.150 0.504 0.022 0.321 -0.373

-0.495 --0.570 -0.067 0.166 0.135 0.103

8ubarc.

--0.080 0.127 0.066 1.162 0.263 --0.045

W. Pac.

0.037 -0.131 -0.134 -0.346 --0.032 --0.053

• 'Imp.

0.804 -0.189 2.292 0.163 -0.014

0.032 0.498 4.018 0.700 1.478 0.593

-0.001 0.044 0.075 0.331 0.005 -0.078 0.392

0.004

-0.212 --0.036 --0.122 0.787 1.218 0.001 0.032 -0.037 -0.212 -0.324 0.762

0.316

0.026 -0.017 0.213 0.055 0.198 0.203 2.010

1.952 1.759 1.890 0.068 --0.023 0.830

Trans.

0.070 -0.672 -0.202 0.133 -0.098

-0.452 -0.207 0.192 -0.292 0.298 -0.572

0.001 0.036 -0.462 -0.722 --1.592 -0.328 -0.003

0.013

--2.522 0.765 4.493 0.043 0.351 --1.817 -0.289 -0.303 2.139 0.407 0.812

0.968

0.993 -0.286 -0.693 0.146 0.325 -0.247 -0.492

0.048 0.405 -0.255 --0.127 -0.132 -0.033

Austnd.

-0.446 0.117 --1.306 ---0.146 --0.074

--0.149 0.076 --1.248 --0.370 -0.613 -0.026

0.030 0.026 -0.134 0.119 -0.437 -0.041 -0.175

0.025

0.331 0.072 0.198 0.248 --0.263 0.247 -0.148 0.701 0.153 0.245 0.747 0.735

-0.559 -0.132 0.080 0.054 -0.145 --0.057 6.032

-0.624 -0.286 -0.603 --0.236 --0.056 -0.113

B. CenL

0.010 -0.122 -0.096 --0.808 0.152

--0.005 0.114 0.412 -0.061 -0.350 --0.172

0.008 0.023 -0.217 --0.594 --0.102 -0.064 0.006

0.020

--2.288 --0.604 --2.157 -0.004 0.277 2.726 0.116 -0.165 4.637 0.136 0.021

0.361

--1.203 0.293 0.746 0.518 -0.430 0.064 --0.136

0.067 -0.079 -0.279 -0.332 0.574 --0.027

N. Guinea

#812, Molina-Cruz, 1977a #836C, Molina-Cruz, 1977a #22, Dow, 1978 #152, Renz, 1973, pi.1.11 #818, Molina-Cruz, 1977a #819, Molina-Cruz, 1977a #13, Dow, 2978

sachs, 1973, pl.2.6b Sp. #NT, Molina-Cruz, 1977a Sp. #34, Dow. 1978 8p. #N42, Molina~h~z, 1977a Sp. #N14, Molina~uz, 1977a

Sp. #N27, Molina-Cruz, 1977a Sp. #N29, Molina-Cruz, 1977a 8p. #40, Dow, 1978 Sp. #N38, Molina-Cruz, 1977a Sachs, 1973, pl.2.50 Sp. #19, Dow, 1978

Petrushevskaya, 1967, fig. 50, I Sp. #I, Dow, 1978 8p. #N2, Molina-Cruz, 1977a Sp. #20, Dow, 1978 Sp. #N9, Molina-Cruz, 1977a Sp. #N1, Molina-Cruz, 1977a Nigrini, 1970, I)1.3.10, 11

Petrushevskaya, 1967, fig. 50, II, IV

Sp. #554, Molina-Cruz, 1977a Sp. #24, Dow, 1978 Nigrini, 1970, pi.1.3 Nigrini, 1970, pi.1.2 8p. #88, Molina-Cruz, 1977a Sp. #16, Dow, 1978 Sp. #340, Molina-Cruz, 1977a Sp. #$1, Molins-Cruz, 1977a Benson, 1966, pi.8--4,5 Sp. #$30, Molina-Cruz, 1977a Sp. #33, Renz, 1973, I)1.3.12 Sp. #11, Dow, 1978

8p. Sp. 8p. 8p. 8p. 8p. Sp.

81). #83, Molina-CYuz, 1977a 8p. #6, Dow, 1978 8p. #85, Molina-Cruz, 1977a 8p. #836A, Molina-Cruz, 1977a Benson, 1966, pi.15.1 8p. #87, Molina-Cruz, 1977a

8pecise description

TABI~ II The 44 spacise end 8pecise groups used in the ~ l y s i s of the Temperate/Tropical data set; the relative importance (scaled factor ecores) of each species in defining the seven factors is siren alon8 with recent references to dsecription8 and illustrations

t~O CO GO

234 above restrictions (Table II). Because the larger number of usable species in the temperate-tropical data allows a more detailed analysis, the Pan-Pacific data and the temperate-tropical subset of data are treated separately in this study.

Species grouping The Q-mode factor analysis used in this study (Klovan and Imbrie, 1971)groups individual samples based on the similarity of the proportions of the species present. It describes these samples in terms of factors which, in turn, are described in terms of the contribution that each species makes to each factor. In the sense that individual factors can be ch~xacterized by a few species which tend to vary concomitantly in abundance, these factors can be considered assemblages. Herein "assemblage" is used synonomously with "factor". It should be remembered, however, that these assemblages are mathematical constructions based on the observed occurrence of species. Each species makes some contribution to the description of every factor, although in some cases the contribution may be very small, or even negative in effect. Similarly, each factor makes some contribution (sometimes called factor loading) to every sample. These loadings also may be either positive or negative. The usefulness of this approach lies in its ability to simplify the large matrix of observed data by reducing it to a few mathematically independent (orthogonal) factors which account for most of the variabilityin the data and which can be both mapped and statistically related to physical measures of the oceanic environment.

Results

The Pan-Pacific data set: modern distribution The Radiolaria were examined in 476 surface sediment samples from the Pacific Ocean (Fig. 1). Of these only 324 samples contained

sufficient radiolarian tests far quantitative analysis (Appendix I). Tests tend to be highly or completely dissolved in samples taken beneath the central water masses of the North and particularly the South Pacific (Fig. 1). This appears to be especially true in the eastern portion of these gyres where only a few samples containing moderately preserved radiolarian tests were found. A Q-mode factor analysis of these 324 samples yielded seven factors, which account for 93.4% of the variance in the data. The first factor dominates the temperate and tropical region (Fig. 1A). Of the species which define this factor, Tetrapyle octacantha, Stylochlamydium asteriscus and Ommatartus tetrathalamus are the most important. The distribution of the Tropical Factor broadly outlines the equatorial flow r~gime. It is distinctly separate from the areas of the California and Peru--Chile Currents, the eastern boundary currents which feed into the equatorial system. However, samples from beneath the western boundary currents, particularly the Kuroshio, show high values for this factor. Based on the distribution of this assemblage and the species important to its description (Table I), it appears similar to the "Subtropical Factors" of both Robertson (1975) and Molina-Cruz (1977a). One additional factor has a distribution that is restricted to the tropical region (Fig. 2A). It is of lesser ~mportance in that it accounts for only 3.4% of the total variance in the data, however, it is clearly associated with very warm tropical waters of the western Pacific. A few samples are found in the eastern tropical Pacific which contain moderately high values for this factor. These appear in the regions of counter current flow and at the fringes of the more productive equatorial waters. Ommatartus tetrathalamus also appears as an important species of the Western Pacific Factor, but in this assemblage it is found in association with Euchitonia elegans/ furcata, and Dictyocoryne profunda. Species in samples from the cooler, productive waters of the eastern boundary currents and the western subarctic are best

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I

90"

Fig. 1. Pan-Pacific Tropical Factor: A, modern distribution (48.8% of variance in surface data); B, distribution at 18,000 B.P. Filled circles indicate location of samples used in the factor analysis and in defining the mapped patterns• Open circles indicate samples not used in mapping because their factor values do not conform to the general geographic distributions indicated by surrounding samples• Open stars indicate samples which contain too few radiolarian tests to be used in the analysis (see Appendix I, II). Contour lines and shaded areas indicate geographic patterns of factor values.

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237

described by a factor which has very little overlap in distribution (Fig. 3A) or in species composition (Table I) with the Tropical and Western Pacific Factors. This assemblage is dominated by Theocalyptra davisiana, 8iphocampe aquilonaris, and 8tylodictya validispina. The largest values for this factor are found in the western subarctic and Sea of Okhotsk where Theocalyptra davisiana reaches its highest percentages. This factor encompasses the distributions of two assemblages recognized by an earlier, more detailed study of the western North Pacific (Robertson, 1975): the "Davisiana Factor", limited in its distribution to the Sea of Okhotsk area and dominated by Theocalyptra dauisiana, and the "Subpolar Factor". It is also similar to the combined distributions of tile "Polar" and "Subarctic" Factors of Sachs (1973). In both these studies of the subarctic Pacific, a more detailed analysis of a larger number of species (35 species in Robertson, 1975; and 58 in Sachs, 1973) allowed a much finer resolution of the water masses. This study emphasizes the basic similarity of Robertson's (1975) "Davisiana" and "Subpolar" Factors with Sachs (1973) "Polar" and "Subarctic" Factors and reproduces the same general patterns of their combined distributions even though the list of species that are included in the analysis is reduced. It also indicates that, based on the species considered in this study, the make-up of the Chile, Peru and Backwater Factors of MolinaCruz (1977a) bears a strong resemblance to the assemblages found in the western subarctic and in the region of the California Current. Samples from the eastern Subarctic and Transition Zone of the North Pacific are best described by a factor in which a number of species are impoaant: Actinomma medianum, Actinomma sp., Cenosphaera cristata, Lithelius minor, 8iphocamp~ acquilonaris, Theoconus zancleus. This assemblage is similar in make-up and distribution (Fig. 4A) to the "Transitional Factors" of Robertson (1975), Sachs (1973), and Moore (1973a). There are also

similarities between this assemblage and the "Transitional" and "Subantarctic" Factors of Dow (1978) as well as the "Subantarctic" Factors of Lozano and Hays (1976), in that all these groupings include both Lithelius minor and Theocalyptra bicornis as important species in their description. These latter two studies of the Antarctic region made use of somewhat different species counting groups and included some species which occur only in the southern hemisphere (e.g. Antarctissa strelkoui and Triceraspyris antarctica). In this study, moderate values (0.3--0.4) of the Transitional Factor are found in the southern hemisphere samples from 30 °S to 50 °S latitude and extend further to the north along the coast of South America in what appears to be at least a partial analog of the "Chile" Factor of Molina-Cruz (1977a). The "Chile" Factor is dominated by Lithelius minor, a species important to the description of the Transitional Factor used in this study. Samples from the high latitudes of the southern hemisphere delineate the distribution of a single factor which is seen nowhere else in the Pacific Ocean. This distribution is dependent on two dominant species of the assemblage: Antarctissa strelkovi and A. denticulata. These species occur only in the polar to subpolar regions of the Antarctic (Fig. 5A). They also dominate the Antarctic Factors of Lozano and Hays (1976) and Dow (1978). A mid-latitude factor of only minor importance in the data set has its highest values in the area of the central water masses, particularly in the eastern regions (Fig. 6A). In the northern hemisphere, samples with moderately high values extend up into the central area of the Alaskan Gyre. The East Central Factor is dominated by Lithelius minor and thus is similar to the Chile Factor of MolinaCruz (1977a). This species is also important (along with 8tylochlamydium asteriscus and Actinomina medianum) in the factor which has its highest values in the western part of central water masses and in the temperate waters south of Australia (The Temperate

238 120.

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242

Factor, Fig. 7A), and is one of the several important species in the Transitional Factor (Table I, Fig. 4A). The location of samples devoid of radiolarian tests indicate that tests are poorly preserved in regions where the East Central Factor has its highest values. Thus, it appears that the separation of this factor as a distinct, almost monospecific assemblage (in terms of the 28 species studied) may be at least partially a result of dissolution of the radiolarian tests. Resistance of Lithelius minor to such dissolution may explain dominance of this form over other less resistant species which define the Temperate and Transitional Factors. The Temperate Factor (Fig. 7 A ) h a s a distribution which almost completely overlaps that of the Transitional Factor in the southern hemisphere (Fig. 4A). In the northern hemisphere its distribution is more irregular, but generally occupies the area to the south of the Transitional Factor. It is predominantly a southern hemisphere factor, with the largest values found south of Australia. Its species make-up indicates that it is allied to the Subantarctic Factor of Dow (1978) and Subtropical Factor of Lozano and Hays (1976). The rather poor definition of the central water masses by these factors may be a result of the limited number of species in the data set and to their method of selection. The most common species found by this study in samples from the central water mass areas are those of the stylosphaerid and collosphaerid groups. These species were eliminated from consideration because they had not been included in counts made by previous investigators. The Pan-Pacific data set: distribution at 18,000 B.P. The CLIMAP project (CLIMAP, 1976) has identified the 18,000 B.P. level in approximately 120 cores from the Pacific Ocean, 105 of which are used in this study (Appendix II). The selection of this level has been

based primarily on oxygen isotope stratigraphy (Shackleton, 1977). In addition to oxygen isotope measurements, some cores have lithologic and faunal stratigraphy (e.g. Thompson and Saito, 1974; Robertson, 1975). These cores were used'for correlation to near-by cores which had only lithologic or faunal information. Species that were counted in the analysis of the modern assemblages were also counted in the 18,000 B.P. samples. The down-core samples were described in terms of the radiolarian factors that were derived from the surface sample counts. Because coverage for the 18,000 B.P. factor distributions is not as complete as that of the surface sediments, the exact boundaries of these distributions are not as clearly defined. At 18,000 B.P., the Tropical Factor (Fig. 1B) dominates the low-latitude region and appears to have had the same general distribution that it has in modem times (Fig. 1A). The details of some regions, however, are different. For example, in the southern hemisphere, the area of highest factor values (~0.8) extended further to the south between Australia and New Zealand and off the coast of South America. A slight increase in the dominance of the tropical assemblage in low latitudes at 18,000 B.P. is indicated by the diminished importance of the Western Pacific Factor (Fig. 2A, B), particularly in the northern hemisphere. There does appear to be some slight increase in the Western Pacific Factor in the central tropics of the South Pacific; however, the coverage in this region is sparse in both the modern and 18,000 B.P. maps. The northern boundary of the Tropical Factor was shifted slightly to the south; and in the northwestern Pacific, where control is good, the gradient of factor values across this boundary does not appear as sharp as it is in the modern map. This is also apparent in a more detailed investigation of the subarctic Radiolaria (Robertson, 1975) but disagrees with the sharper gradient found by Sancetta (1978) in the diatom assemblages

243 120.

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Fig. 7. Pan-Pacific, Temperate Factor: A, modern distribution (9.8% of variance in surface data); ]3, distribution at 18,000 B.P. Sample locations, shading and contours as in Fig. 1.

244 of this area. With the broader geographic coverage of this study, we can see high values for the Tropical Factor do not extend to the coast of Japan (as in the modem distribution), but rather bend to the south. The decreased gradient in the Tropical Factor along its northern boundary is accompanied by an expansion to the south of the Subarctic Factor (Fig. 3A, B) and a southwestern extention of the Transitional Factor (Fig. 4A, B). In addition to the lower sea surface temperatures (Robertson, 1975; Sachs, 1975; Sancetta, 1978) the changes in factor distributions and gradients in the Northwestern Pacific suggests increased mixing along the North Pacific Drift and a possible southward submergence of the subarctic radiolarian assemblage beneath the tropical surface waters. The southward penetration of the Subarctic and Transitional Factors along the coast of Japan suggest that the northward flowing Kuroshio Current was somewhat displaced t(, the east by the southward flowing Oyashio Current and that at 18,000 B.P. the mixing, zone between these cold and warm currents extended to the southernmost islands of JapmL The Subarctic Factor appears to have been just as important in the regions of the California and Peru-Chile Current Systems at 18,000 B.P. as it is in modem times, with perhaps a slight increase in importance off Oregon, off southwestern Mexico, and along the coast of South America. Perhaps the most surprising difference in the ice-age distribution of this factor lies in the area south of Australia where values greater than 0.6 occurred at 18,000 B.P., but where no sample has a value higher than 0.2 in modern times. This curious appearance of what is now primarily a subarctic assemblage in the subantarctic of the ice-age is a result of the behavior of a single species, Theocalyptra davisiana. Hays ~ al., (1976), noted that this species never occurs in proportions greater than about 5% in the modern fauna of the Antarctic but commonly reached 20--30% at the time of the last glacial maximum. The only reported modem

analog of such high percentages of this species is found in the Sea of Okhotsk (Robertson, 1975). Thus, it is an important species in the modem Subarctic Factor (Table I, Fig. 3A) and when T. davisiana reached high percentages in the subantarcfic radiolarian fauna of 18,000 B.P. the resultant assemblage was most closely approximated by that of the modem subarctic. The Transitional Factor appears to be displaced equatorward in both the northern and southern hemispheres at 18,000 B.P., particularly in the eastern parts of the ocean (Fig. 4A, B). In the southern hemisphere there is an indication of a slight increase in the importance of this factor in the extreme eastern equatorial region. In the northern hemisphere, where control is better, the area of higher values is not only shifted southward, but also compressed. This compression is effected mainly by the expansion of the Subarctic Factor. There is very little control in the Antarctic region for the 18,000 B.P. reconstruction of factor distributions (Fig. 4B), but the data available are consistent with more detailed studies of the Antarctic (Hays et al., 1976; Dow, 1978) which indicate a slight northward expansion of the Antarctic assemblage. The East Central (or dissolution) Factor shows littlechange in its distribution between ice-age and m o d e m times (Fig. 6A, B). A possible exception to this is seen in the eastern South Pacific where there is no clear indication of its presence at 18,000 B.P. The distribution of the Temperate Factor at 18,000 B.P. is not greatly different from the m o d e m distribution (Fig. 7A, B). However, in all areas, except along the coast of Chile, the factor values are much lower. This may be explained in part by the sparse coverage at mid-latitudes, and in part by the areal expansion of the tropical and subarctic assemblages, particularly in the southern hemisphere.

245

Temperate-tropical Pacific data set: modem distributions In order to obtain a more detailed view of the radiolarian assemblages in the tropical regions of the Pacific, a subset of the PanPacific data was analyzed (Appendix I) using an expanded list of species counting groups (Table II). The Q-mode factor analysis of these data yielded seven assemblages which accounted for 93.4% of the variance in the data. Of these seven factors, three approximated those obtained by the analysis of the total data set and are better depicted in that analysis: one, similar to the Subarctic Factor, has its highest values in the regions of the Peru--Chile and California Currents; a second, similar to the Transitional Factor, has its highest values poleward of 40 ° latitude in both southern and northern hemispheres; and a third has a distribution and species dominance nearly identical to that of the East Central Factor. Of the remaining four factors two, the Tropical and Western Pacific Factors have clear analogs in the Pan-Pacific analysis (cf. Figs. 1A and 8A; Figs. 2A and 9A). In this analysis, the Tropical Factor is dominated by a single species, Tetrapyle octacantha. Its distribution clearly defines the eastern, more productive areas of the North and South Equatorial Currents and indicates some areas of possible return flow in counter currents (Fig. 8A). The highest values for this Factor (0.8) are found in the equatorial region to the east of 180 ° longitude and off Japan in the northernmost part of the Kuroshiro Current. The Western Pacific Factor is characterized by six important speciev, all of them spumellarians: Euchitonia elegans/furcata, Polysolenia

spinosa, Ommatartus tetrathalamus, Stylochlamydium asteriscus, Dictyocome profunda, and 8pongaster tetras. This assemblage is associated with the western tropical gyres where the warmest waters of the Pacific Ocean are found (Fig. 9A). Moderately high values extend to the east in the regions of counterflow between the wind~lriven equatorial currents.

Two other tropical factors are distinguished in this treatment of the data which are not brought out in the previous analysis. Both are located in the extreme western Pacific in the area of the low-latitude Indo-Pacific connection. The Australian Factor (Fig. 10A) has its highest values in tropical and subtropical latitudes off the northeastern coast of Australia. It is similar to the Western Pacific Factor in species make-up (Table II), but has a higher proportion of Polysolenia spinosa and a reduced importance of such species as Ommatartus tetrathalamus and

Spongaster tetras. The New Guinea Factor (Fig. l l A ) is found north of New Guinea and extends eastward as a narrow tongue of moderate to low values in regions of counterflow. It too has a species make-up similar to the Western Pacific Factor (Table II), but with a greater proportion of Stylochlamydium asteriscus and 8pongoster tetras, and markedly less Omma-

tartus tetrathalamus and Polysolenia spinosa. Temperate-tropical Pacific data set: distribution at 18,000 B.P. Little or no indication of either the Australian or New Guinea Factor was found in the 18,000 B.P. Pacific (Figs. 10B, l l B ) . The coverage is sufficient to suggest that these assemblages were of practically no quantitative importance during the last glacial maximum. Because of their proximity to the Indo-Pacific passages in the modern ocean, it is suggested that the lowering of sea level and the severe restriction of this complex inter-oceanic connection was at least partially responsible for the apparent absence of these assemblages in the ice-age ocean. The most dramatic change at 18,000 B.P. was in the increased dominance of the Tropical Factor throughout the western Pacific, extending southward into the Tasman Sea and northward toward Japan (Fig. 8B). This expansion was at the expense of the Western Pacific Factor which had a more restricted distribution in both hemispheres (Fig. 9B).

246

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247 120,

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jO o

30"

,....I

30 °

30"

60"

~ 6 0 °

I O"

'SO o

I



I

"

120 •

90 •

Fig. 10. Temperate-Tropic, Australian Factor: A, modern distribution (1.7% of variance in surface data); B, distribution at 18,000 B.P. Sample locations, shading and contours as in Fig. 1.

249 180 e

150•

120"

150 •

90 •

120"

" 60"

60 • -

*.

.

*ii)

;.

. ~

o 30 • -



ego

04J



• ~



Q

~,

. • %oo •

e

* J jii

.

o • o•

• eo

, ~

~

":

- 30 •

O0 O • •



-e

• ° •

o

c,

~



". ,,'..> ~

0""

~

~o

L"

~

~-.

~

.

o

o'o

i e" Z . ."'" . o_ o

e

>

.. "r"

}

o,~ •





e

~o

30 • -

"



..

o o

••

..::

-0 • Oq



ee



• I

oe

"SO" e

'~



• e

e



• •



60"-

I 120"

2 $° ,

~ 150`

I 180 e

50" ,

| 150"

180 • i

150 • i

'

I 120"

120 • I

I 90"

90 ° i

60 °

30"

30 a

" 2 .

~"

.

.6

.o~



30*

30"

° o:

D

60"

60"

i 120 e

! °50e

I

ioUo •

! 150 •

! 120 •

i 90 e

Fig. 11. Temperate-Tropic, Hew Guinea Factor: A, modern distribution (1.6% of variance in surface data); B, distribution at 18,000 B.P. Sample locations, shading and contours as in Fig. 1.

250 In oceanographic terms this can be viewed as the expansion of cooler, more productive waters at the expense of the somewhat warmer, less productive waters that now typify the western Pacific, implying an increase in the average wind
In this type of analysis, the greater the sample density and the more restricted the geographic areas, the more likely that minor factors having geographic coherency and oceanographically meaningful distributions can be separated from random " n o i s e " i n the data. Thus, in this more detailed analysis not only is the assemblage associated with the cooler productive waters of the eastern equatorial currents more clearly separated from those of the western Pacific counterflow, but also two additional assemblages are delineated which form coherent patterns in the western Pacific and which appear to have oceanographic meaning. Only a few samples are involved in these latter two factors, and the variance in the data accounted for by them is small (only about 1.6% each). With a greatly expanded data set, the variance represented by the samples of this assemblage would be difficult to distinguish from laboratory or counting error, and, as with the "Backwater" Factor of Molina-Cruz (1977a) and the "Davisiana (Sea of Okhotsk) Factor" of Robertson (1975), these minor, areally restricted factors are incorporated into the broad oceanic patterns of the Pan-Pacific data set even though they may contain valuable oceanographic information pertinent to a particular area of that ocean. The use of these modern assemblages to describe the 18,000 B.P. samples reveals two major differences in the distribution of radiolarian assemblages during the last glacial maximum. First, in the North Pacific the Subarctic Factor had expanded its area of dominance to the east and south. The area of the Transitional Factor was compressed and no longer reached into the Gulf of Alaska (Moore, 1973a). Together with the Subarctic Factor, it extended further to the south, especially along the coast of Japan. The second major change is seen in the equatorial region where the Tropical Factor, which is found primarily in the central and eastern tropics in modem times, extended completely across the ocean and into the region of the western boundary currents at the glacial maximum.

251

But what caused these changes? If major shifts in assemblage distributions are interpreted as changes in surface water mass distribution, then a change in the dynamic processes which create and maintain these water masses is required -- simple cooling and warming are not enough. In the subarctic, studies by Robertson (1975) and Sancetta (1978) indicate that more than just the expansion of the western subarctic waters took place. Specifically, the conditions which are now peculiar to the Sea of Okhotsk (i.e. freezing in the winter and incomplete mixing in the summer) ranged over much of the subarctic at 18,000 B.P. It has been suggested that these extreme conditions could have been brought about by an increased funnelling of arctic air masses over the North Pacific. With the 3-kin high ice caps of Europe and North America blocking some of the usual pathways to arctic air flow, the intensity and volume of flow across Siberia and out over the subarctic Pacific may have been greatly increased (T. Webb, personal communication). This could have caused the expansion of the nearpolar conditions of the Sea of Okhotsk into much of the subarctic. Furthermore, the increased flow of arctic air is consistent with an intensification and greater southward penetration of the Oyashio Current and increased mixing between this current and the Kuroshio--North Pacific Current system. How the Subarctic Factor came to be important at 18,000 B.P. in the subantarctic is not clear. There is no evidence for a migration of the assemblage. Most of the subarctic species studied are bipolar, however. It appears that oceanographic conditions were created in the subantarctic which allowed an assemblage very much like that of the subarctic to dominate. If the Sea of Okhotsk can be used as an oceanographic analogy, these conditions may have included a low-salinity surface layer and a strong thermal minimum within the upper hundred meters or so. In the low latitudes, the greater extent of the Tropical Factor is consistent with

evidence of increased intensity of the southeast trade winds during the last glacial interval (Parkin, 1973; Molina-Cruz, 1977b; Dauphin, 1977). This would cause an increase in the intensity of advective flow, and through greater divergence along the equator, it would increase the supply of cooler, nutrientrich waters to the photic zone. Thus, the expansion of the area dominated by the Tropical Factcr should not be viewed solely as an advective process, but as a process involving divergence as well. In this way the Tropical Factor was not simply carried westwards, but rather through wind-induced divergence and current shear, the cool, productive waters with which the Tropical Factor is associated were created over a larger region of the tropical ocean. There are several other differences noted in the ice-age Pacific, which because of the small magnitude of the change, or because of sparse control in the region of change, cannot be treated in great detail in this study. The northward movement of Antarctic waters during the last glacial maximum is an important oceanographic change which has been better documented by Hays et al. (1976), Luz (1977), and Dow (1978). The data presented here are consistent with their findings. The intensification of western boundary currents is inferred from the increased influence of the Tropical Factor in these regions. For the eastern margins, there is very little control in the area of California and Peru--Chile Currents; however, there is an indication of increased influence of the Transitional and Subarctic Factors which suggests a cooling and intensification of equatorward flow. Conclusions

These results indicate that the taxonomy of modern Radiolaria, although not nearly complete, is sufficiently well known and agreed upon that published data from several workers can be grouped together into a

252

single study. The advantage of this approach is that it provides a means of tying together and interrelating the more detailed investigat i o n s of specific oceanic regions b y giving an ocean-wide view of the distribution of radiolarian assemblages. These distributions have broad patterns which generally conform with those of the surface water masses of the Pacific. It is thought, however, that a better match between these distributions could be achieved in the mid-latitude regions, if more species could have been included in the combined data, especially those stylos. phaerid and collosphaerid species which inhabit the central water masses. From this and earlier investigations of the Pacific, it is seen that the high diversity of radiolarians and a high sample density can yield great detail in the distribution patterr:s and insight into the relationships between these distributions and the oceanographic processes which control them. In the temperate and tropical Pacific, the flow and cc~unterflow of the equatorial current system is much more clearly seen in the data subset using 44 species. Furthermore this more detailed analysis revealed two factors not detected in the Pan-Pacific data which appear to be related to the flow off northeastern Australian and the tropical connection between the Indian and Pacific Oceans.

An analogous study of the radiolarian fauna in core samples from the 18,000B.P. level showed these latter two factors to be absent in the ice-age Pacific. The major difference in the factor distributions at 18,000 B.P. was an expansion and equatorward migration of the boundaries of the subarctic and Antarctic assemblages, and a westward expansion of the Tropical assemblage. The increase in the area dominated by these factors was accompanied by a diminution of the Western Pacific and Temperate Factors. The Transitional Factor was both decreased and shifted toward the equator. The cause of these changes and the cooling which accompanied them is thought to be an increase in the flow of arctic air across the North Pacific and an increase in the intensity of trade winds. The results of this and earlier studies of the Pacific and adjacent regions (Moore, 1973a; Sachs, 1973, 1975; Robertson, 1975; Hays et al., 1976; MolinaCruz, 1977a; Sancetta, 1978; Dow, 1978) suggest an intensified zonal flow in the Pacific, a general "spin-up" in the circulation of the central oceanic gyres, and a steepening of oceanographic gradients in the subpolar regions. These zonal regions of sharp gradients might be viewed as representing a strengthening of barriers to the meridional transport of heat by the oceans.

253

APPENDIX I Surface samples Surface samples examined and used in this compilation. Data sources are indicated as (1)this study, (2)MolinaCruz (1977a), (3) Robertson (1975), and (4) Dow (1978). Usage in the Q-Mode Factor analysis is indicated by " P " , the Pan Pacific data set; " T " the Temperate-Tropic data subset; " + " samples excluded from the factor analysis because they failed to conform to the general geographic patterns indicated by surrounding samples; and " - - " samples excluded from the factor analysis because they contained too few radiolarian tests. Core No.

Latitude +N --S o ,

Longitude +E --W o ,

Sample depth (cm)

Depth (m)

Data source

Usage

AHF10626 ANTP226G ANTP231G CM-945 CM-946 DWBG-2 E44-24 E44-26 E44-27 E44-31 E45-29 E45-31 E45-44 E45-46 E45-57 E45-77 E45-78 E45-81 E45-83 E47-4 E47-9 E48-20 E48-24 E49-3 E49-10 E49-11 E49-17 E49-18 E49-21 E49-25 E49-32 E49-38 E49-39 E49-41 E49-46 E49-48 E49-50 E50-6 E50-9 E50-15 E50-16 E54-11 FANBG16 FANHMS2G

32 51 --18 35 --17 09 53 54 54 38 21 27 --56 02 --54 01 --53 02 --47 32 --44 53 --46 04 --58 29 --59 45 --57 04 --46 27 --45 02 --43 57 --42 35 --64 07 --66 23 --39 11 --39 06 --45 06 --59 01 --59 39 --48 17 --46 03 --42 11 --49 23 --58 22 --50 51 --50 04 --48 15 --44 04 --42 27 --40 37 --48 02 --52 01 --60 04 --61 03 --57 47 37 11 30 17

--119 33 --176 45 --175 54 149 00 151 15 --126 43 119 54 119 46 119 44 120 14 106 31 107 14 114 07 114 57 114 04 114 25 114 21 114 22 114 26 80 24 78 01 89 23 82 10 109 55 110 08 110 09 90 15 90 19 94 53 94 50 98 28 100 05 100 13 100 03 100 01 100 02 99 55 105 15 105 01 109 59 114 49 81 01 --124 34 --118 14

0--10 0--3 0--3 2--3 2--3 0--5 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0-1 0-1 0-1 0--1 0-1 0-1 0--1 0--1 0-1 3--5 0--3

1400 2472 2238 1070 460 4370 2405 2325 1917 1956 2088 1818 2428 2415 2436 2081 2203 2327 2370 1967 1330 1885 1887 2289 2352 2391 1916 1779 1799 1824 2265 1980 1858 1665 1973 1999 2219 1671 1770 2335 1000 4370 3850 2970

1 1 1 3 3 1 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 1 1 1

T T,P T,P P P -P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P -P T,P

q

54

APPENDIX I

(continued)

Core No.

FAN511G HILO-2G HILO-3G HILO-5G LFGS-48G LFGS-50G LFGS-68G LSDH-68PG LSDH-76PG LSDH-102G LSDH-103G MEN-3G MEN .4.G MEN-5G MEN-34G MFZ-1GC MFZ-2GC002 MFZ-6PG012 MSN-3G MSN-155G MSN-158G MUK-9G MUKI-I-I NOVA-A28 NOVA-A29 NOVA-A30 NOVA-A31PG NOVA-A32PG NOVA-A36 NOVA-A37 NOVA-A40PG NOVA-A48 NOVA-A50 NOVA-A64G NOVA-H20 NOVA-H34 NOVA-HV9GO NOVA-HVl~G OPR-47615 OPR-47620 OPR-476184 OPR-476223 PAP 2G RC8-78 RC8-79 RC8-80 RC8-81 RC8-82 RC8-83 RC8-85 RC8-87 RC8-89 RC8-93

Latitude +N

Longitude +E

~S

~W

37 28 24 22 38 36 36 --11 -- 6 23 27 33 34 36 32 33 31 28 20 15 29 53 51 -- 9 --10 --10 --12 --14 --21 --21 --23 --28 --28 --27 --12 --12 --28 --28 --31 --33 --33 --33 23 --44 --46 --48 --47 --46 --45 --41 --39 --36 --29

0

W

01 15 47 57 35 19 33 19 40 15 29 58 02 04 32 36 47 36 01 09 07 15 14 49 27 15 17 08 41 41 00 12 08 37 53 34 24 10 34 30 09 32 35 47 19 18 57 56 58 34 28 23 22

Sample depth (em)

Depth (m)

2--4 6--11 6--11 5--10 3--5 0--5 2--4 3--6 4--6 0--!~, 2--5 0--2 0--3 0--2 0-2 0--2 0--2 0--2 3--10 0--5 3--~ 3--4 2--6 0--5 0--4 0--4 0--5 0--4 0--3 0--4 0--2 0--4 0--3 0--3 0--4 1--4 0--5 0--4 0--2 2--5 4--6 0-5 0--1 0--1 0--1 4--6 2--4 6--8 2--4 5--7 6--8 2--4 4--6

4350 4560 4700 4850 4617 4599 3922 3080 3560 4850 4450 4250 4640 4460 1240 5100 5100 2008 522O 4992 4075 4540 4214 1774 1013 1161 3558 4582 2148 3125 3617 2220 2253 3182 3063 2629 3403 3489 3770 3040 3610 2860 4169 1756 4949 4997 5130 4308 4738 5022 4583 3900 3157

Data

Usage

source

O f

--125 --127 --134 --143 --127 --125 --124 158 163 --130 --125 --122 --125 --125 --117 --131 136 155 --135 --137 --122 --156 --145 145 145 145 145 152 67 172 164 158 158 168 176 175 159 171 153 165 159 166 --119 --175 --172 --162 --159 --154 --149 --133 --125 --118 --105

21 37 31 58 45 56 06 03 13 58 49 34 15 04 31 43 23 18 12 06 57 57 40 23 25 30 50 55 23 14 58 13 19 59 39 19 15 12 33 02 27 32 53 46 51 54 03 15 45 14 30 06 14

P

T,P T,P P T,P T,P

T,P T,P T,P 4*

T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P P T,P P

T,P P ÷

T,P P

T,P

255 APPENDIX I Core No.

RC8-98 RC9-86 RC9-087 RC9-106 RC9-107 RC9-108 RC9-109 RC9-110 RC9-111 RC9-113 RC9-114 RC9-115 RC9-117 RC9-118 RC9-125 RC9-131

RC9-132 RC9-134 RC10-094 RC10-106 RC10-107 RC10-108 RC10-117 RC10-131 RC10-132 RC10-134 RC10-135 RC10-136 RC10-138 RC10-139 RC10-140 RC10-141 RC10-142 RC10-143 RC10-153 RC10-159 RC10-160 RC10-161 RC10-167 RC10-175 RC10-178 RC10-180 RC10-181 RC10-182 RC10-184 RC10-206 RC10-217 RC10-234 RC10-235 RC10-245 RC10-249 RC10-250 RCl1-166

(continued) Latitude +N

Longitude +E

~S

~W

O

--13 --23 --23 --44 --44 --45 --45 --42 --39 --36 --33 --31 --26 --24 --31 --45 --44 --44 5 ---

4 8

--12 --

6

--14 --15 --13 --12 --10

I

28 33 05 13 13 45 08 52 51 43 41 23 26 31 37 59 47 05 40 16 84 56 49 32 41 17 25 22 05

-- 4 -- 3 02 -- 2 39 -- 1 08 -- 0 48 - - 0 20

14 31 32 33 33 34 37 41 44 45 49 47 50 28 25 11 7 6 43

48 13 29 05 24 35 48 43 05 37 31 13 57 38 50 13 19 17 46

O

Sample depth (cm)

Depth (m)

Data source

Usage

3853 4208 4508 931 902 4314 3351 1917 4777 4751 5453 5376 5634 5720 4125 4603 4709 4570 4356 4590 5127 4200 3523 2933 4502 4603 3902 3977 3563 1781 1679 1904 2294 3074 5460 5894 4621 3587 6092 4014 5808 5663 5698 5561 4986 5479 4338 4281 4737 3680 3233 1734 5841

2 2 2

T,P T,P T,P

#

--92 -- 72 -- 76 179 179 --177 --174 --172 --168 --167 --165 --163 --166 --168 170 156 152 143 --127 --146 --146 --148 --165 157 154 153 153 154 154

35 29 21 33 34 22 34 01 45 03 03 43 47 45 13 54 48 47 20 28 27 19 22 58 36 07 21 32 34

0--1 0--2 2--4 0--1 0--1 0---1 0--1 0--1 0--1 0--1 0--1 0--2 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--I 0--I 0--1 0-1 0--1 0--1 0--1 0-1 0-1 0--1

156 156 156 155

26 59 18 14

0--1 0-1 0-1 0-1

59 03 19 50 00 23 I0 20 08 50 52 04 26 05 06 25 73 03 19 14

0-1 0-2 0-1 0--1 0--1 0-1 0-1 0-1 0-1 0--1 0-1 0-1 0--1 0-2 0-2 0-1 0-1 0--1 0--1 0-1

153 154 162 159 158 150 159 172 175 176 177 179 --170 --146 --129 --129 --098 --087 --084 171

1

1 1 1 1 1 1 1 1

T,P

1

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 3 1 3

3 3 3 1 1 1 1 1 1 1 3

P T,P P T,P T,P T,P T,P T,P T,P

T,P T,P T,P P T

T,P P T P P P P P P T,P

T,P T,P T,P T,P

'256

APPENDIX I (continued) Core No.

RCli-195 RCl1-198 RCll-208 RCll-209 RCll-211 RCll-230 RCll-232 RCll-234 RC12-27 RC12-29 RC12-32 RC12-87 RC12-100 RC12-101 RC12-103 RC12-104 RC12-105 RC12-106 RC12-109 RC12-110A RC12-I14 RC12-115 RC12-116 RC12-117 RC12-118 RC12-166 RC12-205 RC12-210 RC12-213 RC12-214 RC12-215 RC12-217 RC12-218 RC12-219 RC12-220 RC12-221 RC12-223 RC12-224 RC12-225 RC12-227 RC12-228 RC12-230 RC12-232 RC12.401 RC12-402 RC12-410 RC12-411 RC12-412 RC12-413 RC12-415 RC12-416 RC12-417 ~C12-419

Latitude +N

Longitude +E

~8

~ W

O

P

31 51 21 31 5 21 3 39! 1 59 -848 --11 20 --13 19 7 75 9 44 12 99 -229 --26 01 --26 01 --26 00 --26 04 --26 00 --26 01 --25 53 --26 00 --24 46 --22 05 --19 28 --16 25 --12 59 38 49 -828 --24 14 --31 31 --34 44 --35 28 --37 28 --39 30 --41 4,2 --43 42 --46 25 --49 48 --51 73 --53 40 --55 14 --55 35 --55 03 --56 00 40 49 40 11 32 23 35 48 40 41 43 17 41 17 36 24 38 06 40 06

O

Sample depth (cm)

Depth

0--1

4934 5378 4720 4400 4319 3259 3762 3645 1683 3274 4034 5243 4171 4356

Data source

(m)

Usage

e

~--139 59 --13960 --139 58 --140 04 --139 43 --110 48 --106 58 --100 57 --083 97 -"088 02 --092 64 --163 96 --174 38 --174 37 179 44 176 42 179 44 174 01 157 52 154 54 170 26 173 16 175 06 174 30 174 01 145 45 --171 31 --177 36 --170 45 --171 22 --167 54 --160 27 --157 42 --154 37 --151 1'7 --146 03 --138 10 --133 41 --123 08 --111 56 --IO0 18 - - 88 57 -77 17 148 08 150 44 161 19 163 43 166 59 166 54 164 09 166 44 170 01 171 30

0--1 0-.2 0--1 0--1 0--1 0-'1 0-'2 0-'1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0-'1 0--1 0--1 4--6 0--2 0--1 0--2 2--4 6--8 0--2 2--4 0--2 6--8 2--4 2--4 0--2 4--6 5--7 0--1 0--'1 0--'1 0--1 0-'1 0--'1 0--1 0-'1 0--1 0--1

2401

4330 4404 4669

2930 1942 3997 1875 3136 2734 3233 5243 4846 1529 5700 576O 4912 4942 4826 5004 5293 5024 4572 4663 2964 3802 4402 4685 4296 5415 5332 5693 5550

5656 5015 4872 5319 3349 6179

1 1 1 1 1 1 1 2

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 3 3

3 3 3 3 3 3 3

m u

T,P T T T T T,P T,P T,P T,P T,P +

T T

P T,P T

P P P P P P P P P P P P P P P P P

257 APPENDIX I

(continued)

Core No.

Latitude +N

Longitude +E

Sample depth (cm)

Depth (m)

RC12-425 RC13-23 RC13-35 RC13-39 RC13-40 RC13-42 RC13-43 RC13-63 RC13-68 RC13-98 RC13-99 RC13-100 RC13-105 RC13-111 RC13-117 RC14-098 RC14-099 RC14-100 RC14-103 RC14-104 RC14-105 RC14-106 RC14-108 RC14-109 RC14-112 RC14-114 RC14-115 RC14-125 RC14-126 RC14-141 RC14-145 RC14-148 RC15-7 RC15-30 RC15-31 RC15-32 RC15-37 RC15-40 RC15-55T RIS-3G RIS-5G RIS-125G RIS-127G S68-FFC1 S68-PC4 S68-PC8 $68-PC16 $68-PC22 SCAN-5PG SCAN-8PG TRI-8PG TRI-11G TRI-12G

57 27 00 04 --08 28 --15 53 --17 24 --13 26 --12 15 1 35 - - 7 20 --16 59 --16 31 --16 07 - - 6 58 - - 0 32 - - 0 19 36 02 36 58 37 46 44 02 40 19 39 41 45 50 48 10 47 39 50 15 51 38 53 02 60 44 60 00 57 21 56 12 54 27 36 03 --23 30 --25 07 --26 47 --27 04 --27 20 --31 06 24 15 20 19 28 27 28 47 16 00 - - 9 07 - - 7 14 - - 1 36 - - 4 20 41 03 28 12 19 06 23 19 25 58

170 --175 178 --176 176 --173 --171 --153 --152 - - 86

0--I 0--I 0-I 0---I 0--I 0---I 0--I 0--I 0--I 0-2 0--2 0-2 0--I 0--2 0--2 0--I 0-I 0--I 0---I 0--1 0--1 0--1 0-1 0--1 0-1 0--1 0--1 0--1 0---1 0--I 0--1 0--1 0-2 1--3 1--3 1--3 0--2 1--3 0--2 0-4 0-4 0--5 0--4 0--2 4--6 0--2 0-I0 0--I0 0-2 2--4 2--4 2--4 2--4

1531 5218 4740 2116 2798 4729 4872 4420 4043 4437 4684 4570 4173 3252 3733 3871 5652

27 06 01 50 41 39 41 07 16 56

-- 84 34 - - 8 1 17 -- 8 6 01 - - 98 41

--106 143 147 151

54 35 56 31

152 56

154 157 155 159 163 164 161 163 175 173 164 165 177 --133 --141 --138 --135 --129 --127 - - 74 --117 --117 --126 --123 --157 --173 --159 158 1i2 --130 --140 --112 --118

40 33 42 26 27 54 55 46 44 21 26 27 44 46 09 26 24 12 51 56 21 29 38 36 90 50 29 46 04 04 Ol 57 26

--118 26

5892

5365 5579 5630 4823 5446 5821 5532 5398 3757 2439 3085 3111 3704 2525 5209 4546 4212 4248 3860 3720 4294 3935 4015 4550 4300 5000 5288 2172 2016 3397 3268 4792 3463 4025 4180

Data source

Usage

3

P T,P

1 1 1 1 1 1 1 1 2

2 2 2 2 2

3 3 3 3

3 3 3 3

3 3 3 3 3 3 3 3 3 1 1 1 1 I 1 2

1 1 1 1 1 1 1 1 1 1 1 1 1 1

T T T T,P T,P T,P T,P T,P T,P T,P T,P P P P P P P P P P P P P P P P P P

T,P + T,P T,P

T,P T,P T,P T,P T,P P

258 APPENDIX I Core No.

TRI-14G TRI-10G V15-33TW V15-46TW V15-56TW • V16-127 V16-129 V16-131 V16-133 V16-134 V18-311 V18-314 V18-319 V18-324 V18-328 V18-337 V18-349 V19-29 V19-30 V19-36 V19-38 V19-39 V19-40 V19-41 V19-47 V19-64 V19-65 V19-068 V19-80 V19-87 V19-88 V19-89 V19-090 V19-102 V19-105 V19-108 V19-109 V19-112 V20-029 V20-47 V20-48 V20-057 V20-64 V20-66 V20-68 V20-74 V20-85 V20-88 V20-095 V20-119 V20-120 V20-121 V20-122

(continued) Latitude +N

Longitude +E

~S

~W

O e

28 15 22 27 - - 6 08 --12 51 --34 22 --54 30 --59 22 --59 19 --61 57 --61 54 - - 3 37 - - 1 14 4 14 8 46 10 16 14 31 6 04 - - 3 35 - - 3 23 --11 59 --12 30 --12 43 --13 13 --14 06 --17 00 --16 56 --16 65 --15 37 --18 08 --12 15 --11 06 - - 9 48 - - 9 11 8 47 ' I I 58 12 19 11 51 11 40 8 09 14 23 14 26 17 21 23 21 28 00 30 58 41 04 44 54 40 11 33 53 47 57 47 24 46 58 46 34

84

28

77 45 --163 19 --142 53 -- 1 7 2 4 -- 9 5 0 3 - - 91 15 --127 41 --122 55 --117 00 --107 09 --103 05 - - 96 18 --085 43 - - 83 56 --

--

83

31

--

81

31

--

86

39

--

89

08

--

92

53

96 --111 --121 --124 --131 --169 --173 --174 --176 --177 160 156 149 142 135 --117 --145 --145 --153 --155 --151 --146 --132 --143 --151 --164 168 167 164 161 --

Depth

2--4 2--4 0--2 0--2 0--3 0--1 0--2 0--2 4--6 4--6 0--1 0--1 0--1 0--1 0--1 2--3 0--1 2--3 0--2 0--1 0--1 0--1 0--1 2--3 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0-1 0--1 0-2 0-1 0--2 0--1 0-1 0-1

4112 4121 4040 4385 4137 4471 3651

(m)

Data source

Usage

1

T,P

2

T,P. T,P T,P

O

--118 04 --119 10 - - 82 41 --

Sample depth (cm)

12 12 12 38 58 21 30 53 26 10 43 40 10 00 52 06 21 21 52 52 10 48 22 37 39 47 47 45 16 41

5029 5062 5138 4559 4495 4160 3517

3939 3891 1818 3157 3091 4731 4276 4173 3693 3248 3422 3570 3867 4199 4839 4621 4497 4212 5358 5017 5810 5879 4294 4773 4116 4986 4640 5106 4204 5338 5788 3749 3817 5081 5804 2739 6216 5859 5563

4-

2 2

1 1 1 1 1 1 1 1 1 1 1 1 1 2 2

2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 3 3

4-

P P P P T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P P T,P T,P T,P

T,P +

T

T,P T,P

T,P

T,P T,P P P P P

259

APPENDIX I Core No.

V20-123 V20-124 V20-126 V20-127 V20-128 V20-129 V20-131 V20-136 V20-137 V20-138 V20-146 V21-029 V21-030 V21-034 V21-036 V21-040 V21-042 V21-044 V21-45 V21-48 V21-54 V21-55 V21-56 V21-57 V21-65 V21-67 V21-70 V21-071 V21-073 V21-074 V21-075 V21-080 V21-083 V21-90 V21-097 V21-099 V21-101 V21-115 V21-126 V21-135 V21-138 V21-139 V21-141 V21-145 V21-146 V21-147 V21-148 V21-151 V21-162 V21-163 V21-177 V21-180 V21-189

(continued) Latitude +N

Longitude +E

~S

~W

O

0

46 45 42 40 38 37 36 32 29 28

15 50 09 17 47 41 20 55 51 52 5 55 0 57

-- 1 13 -- 5 22 -- 818 -- 5 31 -- 4 20 -- 6 10 -- 7 13 - - 9 51

--18 58 --21 07 --23 47 --2b 36 23 58 24 58 27 05 27 54 29 28 29 51 30 04 34 02 27 54 23 57 23 41 23 32 23 29 19 52 13 00 21 28 26 02 27 47 30 48 34 03 37 41 39 33 42 05 51 16 58 33 58 02 33 52 28 24 16 49

O

Sample depth (cm)

Depth

0--1 0---1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1

4903 5534 5515 5583 5612 5766 5858

(m)

Data source

Usage

e

157 154 155 156 157 156 151 142 137 135 135 -- 89 - - 89

55 30 52 55 24 35 00 32 58 33 31 21 41

-- 93 -- 96 --106 --112 --116 --119

22 14 46 22 59 90

0--1 0"-1 0--1 0--1 0--1 0--1 0--1

--126 --137 --138 --140 --142 --176 176 166 162 154 150 147 138 140 144 136 132 131 132 127 130 139 144 154 164 163 162 160 163 --177 --176 --160 --159 --154

37 36 49 26 23 51 16 04 31 36 50 41 23 03 23 05 14 01 08 03 03 29 18 04 50 02 05 36 38 13 07 08 11 11

0--1 2--4 2--4 4--6 0--2 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--2

6306

3919 4244 4702 712 617 3081 3649 3182 4142 4535 4199 3922 4071 4268 4318 4343 5365 5879 5954 5013 5872 6015 6119 4400 3702 5841 4868 4158 5293 5484 5075 5929 4418 6009 5821 6088 3968 5256 5477 5055 2318 3270 6022 5676 4947

P P P P P P P T,P T,P T,P +

T,P T,P T,P T,P T,P T,P T,P T,P

T,P T,P

P T,P T,P T,P T,P T,P T,P P T,P T,P T,P T,P P P P P P P P P

260 APPENDIX I (continued) Core No.

V21-203 V21-206 V21-207 V24-040 V24-046 V24-049 V24-051 V24-052 V24-054 V24-056 V24-064 V24-065 V24-071 V24-073 V24-074 V24-076 V24-078 V24-087 V24-089 V24-095 V24-100 V24-104 V24-112 V24-113 V24-114 V24-115 V24-117 V24-121 V24-122 V24-139 V24-141 V24-143 V24-146 V24-147 V24-150 V24-152 V24-153 V24-154 V24-155 V24-156 V24-158 V24-159 V24-160 V24-163 V24-164 V24-165 V24-168 V24o170 V24-!71 V24-173 V24-174 V24-]75

Latitude +N

Lon~tude

Sample depth

+E

(cm)

~8

~W

O

I

4 23 1 37 0 01 3 04 1 40 0 49 1 40 1 54 1 51 2 14 4 10 6 40 19 18 16 29 14 53 13 18 10 2 8 1 9 O4

20 52 27 36 16 08 4 51 7 56 11 19 14 42 17 55 18 36 18 30 18 32 3 31 2 52 2 04 1 50 7 40 - - 2 12 -- 3 18 - - 4 30

--12 --12 --13 --15 --16 --18 --15 --13 --15 --16 --13 --14 --11 --11 --11

03 52 49 55 33 07 27 52 21 20 31 18 46 07 25

O

Data source

Usage

3928 3334 3352

1 1 1 1 1 1 1 1 1 1 1 1 1 1

T,P T,P "T T,P T,P T,P T,P T,P T,P T,P T,P T,P

3

P

#

--110 53 --103 10 --100 17 - - 97 08 --105 09 --112 44 --120 20 --124 49 --131 42 --136 15 --159 04 --157 32 --161 19 --166 47 --169 51 --172 55 --177 46 161 23 165 07 177 46 179 44 170 55 153 22 152 05 150 33 149 09 142 22 128 23 125 28 132 26 132 28 141 18 144 53 151 25 155 42 153 32 153 28 1511~ 150 12 149 04 146 51

146 147 153 153 152 146 146

Depth (m)

24 36 34 58 21 52 53

145 1 148 06 150 52 150 18

0--1 0--1 0--1 0--1 0--! 0-1 0--1 0--1 0-1 0--1 0-1 0--1 0--1 0-1 0--1 0--1 0--1 0--1 0-1 0--1 0-1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0--1 0-1 0--1 0--1 0--1 0-1 0--1 0--1 0-1 0--1 0--1 0-1 0--1 0-1 0--1 0-1 0--1 0-1 0-1 0--1 0-1 0-1 0--1 0--1

3204 3574 3878 4409 4702 4479 4341 3933 4726 5092 5234 5669 5680

5312 4879 5544 5287

5330 4501 4964 5861

5993 5544 3706 5431 4870 3350 4383 3191 4526 4918 1849 4422 4103 4235 4559 4519 1754 1403 1007 4656 4526 4063 1785 2243 2714 3360 1004 2618

1 1 1 1 1 1 1 1 1 1 I 1 I 1 I 1 1 I I 1 1 1 1 1 1 1 1

T,P T,P T,P T,P T,P T,P P T,P T,P T,P T,P T,P T,P T,P T,P T,P

I

1 1 I 1 I 1 1 1 I

T,P T,P

261 APPENDIX I

(continued)

Core No.

V24-176 V24-177 V24-178 V24-182 V24-183 V24-184 V28-234 WAH-SF2 Y69-71M Y69-73M Y69-80M Y69-103P Y69-104M Y69-106M Y70-1-3P Y70-1-6 Y70-2-34 Y70-2-41 Y70-4-56 Y70-4-59 Y70-5-62 Y70-5-63 Y70-5-64 Y70-5-67 Y71-6-4P Y71-6-12 Y71-6-14 Y71-6-18MG2 Y71-7-27 Y71-7-28 Y71-7-30 Y71-7-32 Y71-7-33 Y71-7-35 Y71-7-36 Y71-7-38 Y71-8-70 Y71-8-77 Y71-9-84 Y71-9-85 Y71-9-86 Y71-9-87 Y71-9-88 Y71-9-89 Y71-9-91 Y71-10-116 ZAP-2G ZTS-39G ZTS-40G ZTS-41G ZTS-42G ZTS-44G 6509-25A

Latitude +N

Longitude +E

~S

~W

O

I

--12 14 --13 12 --14 06 --17 36 --15 20 --12 52 --07 13 0 03 0 06 1 27 -- 1 01 -- 0 05 -- 2 18 2 59 45 00 45 00 54 01 57 10 53 01 50 23 50 30 50 28 49 26 48 17 --14 37 --16 27 --17 40 --16 56 - - I 0 15 --11 01 --10 03 --10 45 --10 0 -- 9 57 --10 08 --10 46 -- 8 42 -- 8 11 -- 5 00 -- 5 02 -- 5 05 -- 5 03 -- 5 00 -- 5 59 -- 5 57 28 27 17 52 28 40 30 12 31 01 31 10 31 18 43 35

O

Sample depth (cm)

Depth (m)

0--1 0---1 0--1 0--1 0-1 0--1 0-1 0-1 0-2 0-2 0--4 1--3 0--5 0--2 0--10 0--12 0--2 0--1 0--2 0--1 0--2 0--2 0--2 0--2 3--4 2--4 1--2 1--2 0 5--7 2--3 2--3 2--3 1--2 4--5 2--3 5--6 0--2 2--4 1--3 4--6 0--2 4--5 2--4 3--5 0-1 0--4 0-6 0-6 0--3 0--4 0--5 0--2

4422 4535 3997 1053 1099 2992 2719 4308 2740 2707 3408 2220 3892 2780 4155 4583 4575 3384 3805 3774 3214 2896 2993 3382 4518 2734 4625 7280 4569 4491 4237 3850 4093 4010 4541 3691 4378 5121 4010 3858 3877 3858 3650 3990 3512 3447 3640 5048 5050 4613 4672 4569 3391

Data source

Usage

e

150 49 149 40 148 50 147 30 146 15 146 12 158 98 --147 98 -- 86 29 -- 86 56 -- 91 51 -- 82 26 -- 81 31 -- 86 33 --136 05 --142 35 --154 47 --141 04 --141 41 --139 15 --132 42 --132 48 --132 46 --132 53 -- 79 07 -- 77 34 -- 75 47 -- 74 21 -- 82 05 -- 85 01 -- 88 41 -- 93 06 -- 92 40 -- 97 56 --102 51 --106 20 -- 82 13 -- 81 36 -- 85 57 -- 87 28 -- 90 47 -- 93 05 -- 99 27 --111 02 --114 52 --116 56 --109 31 --144 55 --143 17 --137 41 --135 57 --133 00 --129 12

m

T,P

T,P T,P T,P T,P 4-

T,P T,P T,P P T,P P P P 4-

T,P T,P T,P

T,P

2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1

T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P T,P P T,P T,P T,P T,P T,P T,P T,P T,P T,P

T,P T,P T,P

262 Core No.

6609-19 6705-2 6705-6 6808-8 6910-2PG 7-TOW72G 7-TOW105

Latitude +N

Longitude +E

--S

--W

43 46 46 46 41 --20 --15

o

,

43 43 25 42 16 24 15

o

--128 --126 --126 --131 --127 --176 --176

Sample depth (cm)

Depth (m)

Data source

Usage

0-2 0-1 0--1 0-2 1--2 0-1 0--2

3503 2787 2730 2539 2615 2730 2163

1 1 1

T,P. T,P T,P

,

41 03 24 01 01 46 49

1

1 1 1

+

T,P -T,P

APPENDIX II 18,000 B.P. cores and samples *Data Source: Samples or species counts were contributed by the following investigators: ( 1 ) T h i s study; (2) A. MoUna-Cruz (1977a); (3) Robertson (1975); (4) Dow (1978); ( 5 ) H . Sachs (personal communication); (6) C. Wenkam (personal communication). *Stratigraphy: The following types of stratigraphy were used to define the 18,000 B.P. Level: " A " Radicarbon dating; " B " oxygen isotope measurements; "C" Faunal counts; " D " Lithologic measurements; " - - " insufficient Radiolaria for analysis at 18,000 B.P. level. Core No.

Latitude +N --S o ,

Longitude +E --W o ,

Depth in core (cm)

Depth of water (m)

*Data source

+Stratigraphy

AHF-10622 AHF-11343 BNFC-43PG E45-62 E45-74 E45-77 E45-79 E50-15 RC8-78 RC8-94 RC9-110 RC9-124 RC9 126 RC9-129 RC10-97 RC10-114 RC10-139 RC10-140 RC10-161 RC10-167 RC10-178 RC10-216 RCl1-172 RCl1-179 RCll-209 RCll-210 RCll-213 RCll-220

32 32 10 --55 --47 --46 --45 --60 --44 --27 --42 --28 --33 --39 --00 --11 --03 --02 33 33 37 50 51 53 03 01 --06 --14

--119 --119 109 114 114 114 114 109 --175 --102 --172 172 168 163 --134 --162 156 156 158 150 172 --151 --164 --145 --140 --140 --140 --139

295--305 279--280 16--19 38--39 40--41 31--32 38--39 21--22 40--43 16--17 30--31 31--32 20--23 32--35 42--43 17--18 30--33 35--36 8-9 44--45 31--32 10--11 70--7] 40--41 33--34 43--44 15--16 11--12

1400 1171 2720 2250 1900 2081 2000 2335 1756 3074 1917 2540 2060 2836 4305 2791 1781 1679 3587 6092 5808 4989 4808 4067 4400 4420 4343 2950

1 1 6 4 4 4 4 4 1 1 1 1 1 1 1 1 1 1 3 3

AD AB BCD C BCD C C C CD B CD ABCD ACD CD D B-CD CD BC CD

3

C

5 5 5 1 1 1 1

C C C ACD BCD C BCD

51 48 30 05 33 27 03 04 47 17 52 45 14 31 55 11 02 39 05 24 48 58 15 30 39 49 08 49

33 51 01 07 26 25 22 59 46 05 01 36 44 08 19 55 26 59 00 23 20 10 53 39 04 03 51 58

263

Core No.

RCll-230 RC12-103 RC12-107 RC12-109 RC12-121 RC12-361 RC12-401 RC12-412 RC12-413 RC12-419 RC13-17 RC13-38 RC13-63 RC13-81 RC13-113 RC14-99 RC14-105 RC14-106 RC15-52 RC15-61 V15-53 V16-122 V17-42 V17-43 V17-44 V18-222 V18-312 V18-318 V18-337 V19-25 V19-27 V19-28 V19-29 V19-30 V19-41 V19-53 V19-55 V19-64 V19-65 V20-85 V20-103 V20-119 V20-120 V20-121 V20-122 V20-123 V20-124 V20-126 V20-129 V21-29 V21-30 V21-33 V21-59

Latitude +N --S o ,

Longitude *E --Wo ,

D e p t h in core (cm)

D e p t h o f Data water source

--08 48 --26 00 --26 00 --25 53 --03 44 15 06 40 49 40 41 43 17 40 06 19 05 --14 31 01 21 --19 01 --01 39 36 58 39 41 45 50 --29 14 --40 37 --33 27 --46 42 03 01 52 --03 34 --38 34 --02 51 03 10 14 31 02 28 --00 28 --02 22 --03 35 --03 23 --14 06 --17 01 --17 00 --16 56 --16 65 44 54 33 59 47 57 47 24 46 58 46 34 46 15 45 50 42 09 37 41 O0 57 --01 13 --03 48 20 55

- - 1 1 0 48 179 44 169 12 157 52 168 23 124 08 148 08 166 59 166 54 171 30 - - 1 7 0 04 177 06 - - 1 5 3 04 --124 14 --103 38 147 56 157 33 155 42 -- 85 59 -- 77 12 -- 73 40 171 30 -- 81 11 -- 82 37 -- 85 07 140 37 - - 1 2 6 12 - - 1 1 8 28 -- 96 18 81 42 -- 82 04 -- 84 39 -- 83 56 -- 83 31 -- 96 12 - - 1 1 3 31 - - 1 1 4 11 --121 12 --124 38 --143 37 --177 50 168 47 167 45 164 16 161 41 157 55 154 30 155 52 156 35 -- 89 21 -- 89 41 -- 92 05 --158 06

46--47 40--43 40--43 20--23 30--33 20--21 260--261 35--36 35--36 60--61 30--31 35--36 55--56 10--11 50--51 98--99 110--111 80--81 12--13 68--69 39--40 30--33 84--85 73--74 75--76 38--39 25--26 15--16 220--221 80--81 110--111 130--131 180--181 170--171 30--31 38--39 19--20 13--14 15--16 4--5 23--24 21--22 54--55 59--60 80--81 79--82 78--79 111--112 139--142 165--166 250--251 45--46 16--17

3259 2401 3115 2930 3519 3828 5415 5656 5015 6179 3374 2867 4420 3751 3195 5652 5630 4823 3780 4078 4085 1265 1814 3147 3358 1904 4614 4191 3891 2404 1373 2720 3157 3091 3248 3058 3177 3570 3867 3817 3442 2739 6216 5859 5563 4903 5534 5515 5766 712 617 3726 2992

Stratigraphy

(m) 1 1 1 1 1 1 3 3 3 3 1 1 1 1 I

ABD C C C C C C C C C C CD D B C C C C B B B CD BCD CD CD CD CD CD A D BD BD BCD BD BD-CD-BDC-CD CD C BC BCD CD C C C C C C D ABD BD B--

264

Core No,

V21-146 V21-148 V21-151 V21-212 V21-214 V24-109 V24-166 V28-201 V28-203 V28-229 V28-230 V28-235 V28-238 V28-239 V28-243 V28-249 V28-255 V28-294 V28-304 V32-126 WAHSFF-2 Y69-71P Y69-73P Y69-106 Y71-6-12 Y71-7-45 Y6604-10 Y6910-2

Latitude +N

Longitude +E

Depth in core

Depth of Data water source

--S

--W

(em)

(m)

68--69 20--21 10--11 60--61 105--106 50--51 150--151 20--21 42--43 40--43 20--21 35--36 36--37 27--28 18--19 18--19 15--16 15--16 72--73 40--41 31--33 174--176 132--133 33--34 24--25 9--10 221--223 117--119

3968 5477 5055 3338 2246 2367 781 3217 3243 3243 2992 1746 3120 3490 2129 2569 3261 2308 2942 3870 4308 2740 2707 2870 2734 3096 3002 2615

o

,

37 41 42 05 52 16 02 5O 03 50 00 26 --16 31 02 46 00 57 --08 24 --05 30 --05 27 01 01 03 15 11 04 14 35 20 06 28 26 28 32 35 19 00 02 00 06 01 27 02 59 16 27 --11 04 43 16 41 16

o

,

163 02 160 36 163 38 -- 85 O8 -- 80 38 158 48 150 47 --173 56 --179 25 167 46 166 45 1 6 0 29 160 29 159 11 138 32 147 52 142 27 139 58 134 08 177 54 --147 59 -- 86 29 -- 87 56 -- 86 33 -- 77 34 --110 06 --126 24 --127 01

Acknowledgements H. Sachs, J. Robertson, A, Molina-Cruz, R. Dow, J. Hayes, J. Lozano, C. Wenkam, and C. Sancetta are gratefully acknowledged for their time, data and helpful discussions. Their own studies, which are referenced herein, contributed greatly to this investigation. The difficult tasks involving the production and compilation of the data used in this study were undertaken by Gaff Lombari and George Steele. They are thanked for their tireless efforts. Tom Webb of Brown University contributed substantially to this paper by offering what the author feels is a most plausible explanation for the marked faunal and floral changes in the ice-age North Pacific. This research was supported by a

3 3 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 1 1 1

Stratigraphy

BC C C CD CD B CD C BC C CD BC BCD BCD CD CD BC BC BC C BD AC BC BC BC BC ACD ABCD

grant from the National Science Foundation (IDOE) to the CLIMAP project at the University of Rhode Island (OCE 75-20358-A01). All raw data and species counts have been filed at the National Geophysical and SolarTerrestrial Data Center of the Environmental Data Service/NOAA in Boulder, Colorado.

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265

Benson, R.N., 1966. Recent Radiolaria from the Gulf of California. Doctoral dissertation. University of Minnesota, Minneapolis, Mo., 577 pp. Bradshaw, J.D., 1959. Ecology of living planktonic foraminifera in the north and equatorial Pacific Ocean. Contrib. Cushman Found. Foraminiferal Res., 10(2): 25--64. Casey, R.E., 1971a. Distribution of polycystine Radiolaria in the oceans in relation to physical and chemical conditions. In: B.M. Funnell and W.R. Riedel (Editors), The Micropaleontology of Oceans. Cambridge University Press, London, pp. 151--160. Casey, R.E., 1971b. Radiolaria as indicators of past and present water masses. In: B.M. Funneil and W.R. Riedel (Editors), The Micropaleontology of Oceans. Cambridge University Press, London, pp. 331--342. CLIMAP, 1976. The surface of the ice-age Earth. Science, 191: 1131--1137. Dauphin, J.P., 1977. Monitoring past trade wind conditions using quartz particle size distributions. EOS, Trans. Am. Geophys. Union, 58(6): 411. Dogiel, V.A. and Reshetnyak, V.V., 1952. Materialy po radiolyariyam severozapadnoi chasti tikhogo okeana. Isslec. Dalnevostochn. Morei S.S.S.R., 3: 5--36. Dow, R.L., 1978. Radiolarian distribution and the late Pleistocene history of the southeast Indian Ocean. Mar. Micropaleontol., 3: 203--227. Dreyer, F., 1889. Morphologische RadiolarienStudien.1. Die Pyiombildungen in vergleichendanatomischer und entwicklungsgeschichtlicher Beziehung bei Radiolarien und bei Protisten ttberhaupt, nebst System and Beschreibung neuer und der bis jetzt bekannten pylomatischen Spumellarien. Jena. Z. Naturwiss., 23, N.S., 16: 1--138. Ehrenberg, C.G., 1844. Einige vod~lufige Resultate seiner Untersuchungen der ihm yon der SIldpolreise des Capitain Ross, so wie yon den Herren Schayer und Darwin zugekommenen, Materialien ttber das Verhalten des kleinsten Lebens in den Oceanen und den gr0ssten bisher zugsnglichen Tiefen des Weltmeeres. Monatsber. K. Preuss. Akad. Wiss. Berlin, Jahrg. 1844: 182--207. Ehrenberg, C.G., 1860. Ueber die organischen und unorganischen Mischungsverh~dtnisse des Meeresgrundes in 19800 Fuss Tiefe. Monatsber. K. Preuss. Akad. Wiss. Berlin, Jahrg. 1860: 765--774. Ehrenberg, C.G., 1861. Ueber die Tiefgrund-Verh~tnisse des Oceans am Eingange der Davisstrasse und bei Island. Monatsber. Preuss. Akad. Wiss. Berlin, Jahrg. 1861: 275--315. Ehrenberg, C.G., 1872. Mikrogeologische Studien ttber das kleinste Leben der Meeres-Tiefgrttnde aller Zonen v,nd dessen geologischen Einfluss. Monatsber. K. Preuss. Akad. Wiss. Berlin, Jahrg. 1872: 265--322.

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