33. Late Quaternary Paleoceanography in the Eastern Equatorial ...

19
Pisias, N.G., Mayer, L.A., Janecek, T.R., Palmer Julson, A., and van Andel, T.H. (Eds.), 1995 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 138 33. LATE QUATERNARY PALEOCEANOGRAPHY IN THE EASTERN EQUATORIAL PACIFIC OCEAN FROM PLANKTONIC FORAMINIFERS: A HIGH RESOLUTION RECORD FROM SITE 846 1 J. Le, 2 A.C. Mix, 3 and N.J. Shackleton 2 ABSTRACT High resolution records of δ l8 0 and relative abundances of planktonic foraminifers were generated for ODP Leg 138 Site 846 for the past 800 k.y., with an average sampling interval of 3.6 k.y. The time scale was constructed by correlating the benthic δ I8 O record to the SPECMAP and ODP Site 677 δ 18 θ time scales using the mapping function technique of Martinson et al. (1981). Our observations show that variations in the foraminiferal assemblages, although influenced by dissolution, are interpretable in terms of changing characteristics of upper ocean waters. Carbonate dissolution as indicated by fragmentation of planktonic foraminifers shows concentrated variance that is coherent with δ' 8 O at the 100 and 41 k.y. orbital periods. At these periods, maximum dissolution occurs during interglacial extremes. This finding differs from previous studies that have indicated that in this region percent carbonate minimum lags global ice volume minimum. N. dutertrei and dextral N. pachyderma dominate the assemblages, but do not show consistent relationships relative to glacial interglacial cycles. However, less abundant species G. ruber, G. menardii, G. glutinata and G. sacculifer show positive and G. bulloides negative correlation with the δ' 8 O record. Q mode factor analysis of the Site 846 assemblages and comparison with modern assemblages suggest the following. Prior to and during interglacials, the area was considerably warmer and more subtropical than at present; during glacials, the area was colder than at present with greater upwelling and advection off the eastern boundary, and possibly a stronger Peru Current; the equatorial "cool tongue" was also possibly stronger. INTRODUCTION A major objective of ODP Leg 138 was to study the history of the equatorial circulation in the eastern Pacific Ocean. A large proportion of such information is contained in microplankton fossil assemblages in deep sea sediments. For example, species compositions of plank tonic foraminiferal assemblages reflect the conditions of surface wa ters in which they lived; the preservation status of the fossil is indic ative of seawater chemistry and/or productivity level at the time. In the eastern equatorial Pacific Ocean, foraminifers have been partially dissolved in most areas as a result of the shallow carbonate lysocline (Adelseck and Anderson, 1978); as a result, previous paleoceano graphic studies in the area that used fossil assemblage data are mostly based on radiolarians (Romine, 1982; Schramm, 1985; Hays et al, 1989). However, the moderate preservation of planktonic foramin ifers at Site 846 provides a good opportunity for paleoceanographic studies using foraminiferal assemblages, thus providing independent evaluation of the results of radiolarian studies. REGIONAL OCEANOGRAPHIC SETTING Site 846 was drilled at 3°5.7'S, 90°49.08'W, at a water depth of 3307 m (Fig. 1). It is located at the eastern end of the South Equatorial Current (SEC) and the northern end of the Peru Current and was designed to examine the history of the Peru Current and its interaction (or lack thereof) with the SEC. Figure 1 shows a generalized surface circulation pattern of the eastern equatorial Pacific Ocean. The circu lation is dominated by the eastern and equatorial parts of two anticy clonic gyres, the California Current and the North Equatorial Current (NEC) in the North, and the Peru Current and the South Equatorial Current (SEC) in the South Pacific Ocean. Between them is the ' Pisias, N.G., Mayer, L.A., Janecek, T.R., Palmer Julson, A., and van Andel, T.H. (Eds.), 1995. Proc. ODP, Sci. Results, 138: College Station, TX (Ocean Drilling Program). 2 University of Cambridge, Godwin Laboratory, Free School Lane, Cambridge CB2 3RS, United Kingdom. 3 College of Oceanography, Oregon State University, Corvallis, OR 97331, U.S.A. eastward flowing Equatorial Countercurrent (ECC). The SEC ex tends across the equator to about 5°N, bordering with the ECC, and its southern boundary is approximately at 10°S (Wyrtki, 1966,1981). The equatorial current system is driven by the trade winds in the region. Seasonal variations of the NEC and ECC are influenced by the position of the northeast trade winds, rather than by their strength. During the Northern Hemisphere summer when the northeast trade winds reach their northernmost position, the NEC and ECC are both intensified. Unlike the NEC and ECC, seasonal variations of the SEC follow the strength of the southeast trade winds, which are most intense during the Southern Hemisphere winter. At the same season, the equatorial upwelling is also intensified. A prominent oceanic feature in the eastern equatorial Pacific Ocean is the existence of a tongue of cool water. Wyrtki (1981) suggested, based on heat budgets, that most of the Equatorial Pacific Cool Tongue reflects shallow upwelling out of the upper portions of the eastward flowing Equatorial Undercurrent (>20°C water), al though a portion could result from the advection off the eastern boundary. Bryden and Brady (1985) emphasized eastward and up ward flow along the outcropping isopycnals, with sources somewhat deeper than those predicted by Wyrtki (1981). This implies that the Cool Tongue reflects basin scale thermocline and sea level structure, rather than cross isopycnal upwelling, in response to local winds. Toggweiler et al. (1991) argued that much of the SEC includes radio carbon depleted water that originates in the subantarctic Pacific. They believed that this water transits eastward in the lower part of the Equatorial Undercurrent (as 11° 14°C water) before upwelling off Peru and advecting westward into the SEC. At present, both radiocar bon and heat budget considerations suggest that northward advection of cool surface water in the eastern boundary current is not important in setting the characteristics of water in the SEC of the Pacific Ocean. Site 846, at 3°S, is probably far enough off the equator that it is not very sensitive to true equatorial upwelling, which only occurs within a couple degrees of the equator (Wyrtki, 1981; Philander, 1990). Instead, it is probably sensitive to a combination of (1) westward advection of recently upwelled water off the eastern boundary and (2) outcropping of cool isopycnals associated with the intensities of large scale tropical Pacific circulation. 675

Transcript of 33. Late Quaternary Paleoceanography in the Eastern Equatorial ...

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Pisias, N.G., Mayer, L.A., Janecek, T.R., Palmer-Julson, A., and van Andel, T.H. (Eds.), 1995Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 138

33. LATE QUATERNARY PALEOCEANOGRAPHY IN THE EASTERNEQUATORIAL PACIFIC OCEAN FROM PLANKTONIC FORAMINIFERS:

A HIGH-RESOLUTION RECORD FROM SITE 8461

J. Le,2 A.C. Mix,3 and N.J. Shackleton2

ABSTRACT

High-resolution records of δ l 8 0 and relative abundances of planktonic foraminifers were generated for ODP Leg 138 Site 846for the past 800 k.y., with an average sampling interval of 3.6 k.y. The time scale was constructed by correlating the benthic δI8Orecord to the SPECMAP and ODP Site 677 δ 1 8 θ time scales using the mapping function technique of Martinson et al. (1981). Ourobservations show that variations in the foraminiferal assemblages, although influenced by dissolution, are interpretable in termsof changing characteristics of upper ocean waters.

Carbonate dissolution as indicated by fragmentation of planktonic foraminifers shows concentrated variance that is coherent withδ'8O at the 100 and 41 k.y. orbital periods. At these periods, maximum dissolution occurs during interglacial extremes. This findingdiffers from previous studies that have indicated that in this region percent carbonate minimum lags global ice volume minimum.

N. dutertrei and dextral N. pachyderma dominate the assemblages, but do not show consistent relationships relative toglacial-interglacial cycles. However, less abundant species G. ruber, G. menardii, G. glutinata and G. sacculifer show positiveand G. bulloides negative correlation with the δ'8O record. Q-mode factor analysis of the Site 846 assemblages and comparisonwith modern assemblages suggest the following. Prior to and during interglacials, the area was considerably warmer and moresubtropical than at present; during glacials, the area was colder than at present with greater upwelling and advection off the easternboundary, and possibly a stronger Peru Current; the equatorial "cool tongue" was also possibly stronger.

INTRODUCTION

A major objective of ODP Leg 138 was to study the history of theequatorial circulation in the eastern Pacific Ocean. A large proportionof such information is contained in microplankton fossil assemblagesin deep-sea sediments. For example, species compositions of plank-tonic foraminiferal assemblages reflect the conditions of surface wa-ters in which they lived; the preservation status of the fossil is indic-ative of seawater chemistry and/or productivity level at the time. Inthe eastern equatorial Pacific Ocean, foraminifers have been partiallydissolved in most areas as a result of the shallow carbonate lysocline(Adelseck and Anderson, 1978); as a result, previous paleoceano-graphic studies in the area that used fossil assemblage data are mostlybased on radiolarians (Romine, 1982; Schramm, 1985; Hays et al,1989). However, the moderate preservation of planktonic foramin-ifers at Site 846 provides a good opportunity for paleoceanographicstudies using foraminiferal assemblages, thus providing independentevaluation of the results of radiolarian studies.

REGIONAL OCEANOGRAPHIC SETTING

Site 846 was drilled at 3°5.7'S, 90°49.08'W, at a water depth of3307 m (Fig. 1). It is located at the eastern end of the South EquatorialCurrent (SEC) and the northern end of the Peru Current and wasdesigned to examine the history of the Peru Current and its interaction(or lack thereof) with the SEC. Figure 1 shows a generalized surfacecirculation pattern of the eastern equatorial Pacific Ocean. The circu-lation is dominated by the eastern and equatorial parts of two anticy-clonic gyres, the California Current and the North Equatorial Current(NEC) in the North, and the Peru Current and the South EquatorialCurrent (SEC) in the South Pacific Ocean. Between them is the

' Pisias, N.G., Mayer, L.A., Janecek, T.R., Palmer-Julson, A., and van Andel, T.H.(Eds.), 1995. Proc. ODP, Sci. Results, 138: College Station, TX (Ocean Drilling Program).

2 University of Cambridge, Godwin Laboratory, Free School Lane, Cambridge CB23RS, United Kingdom.

3 College of Oceanography, Oregon State University, Corvallis, OR 97331, U.S.A.

eastward-flowing Equatorial Countercurrent (ECC). The SEC ex-tends across the equator to about 5°N, bordering with the ECC, andits southern boundary is approximately at 10°S (Wyrtki, 1966,1981).

The equatorial current system is driven by the trade winds in theregion. Seasonal variations of the NEC and ECC are influenced bythe position of the northeast trade winds, rather than by their strength.During the Northern Hemisphere summer when the northeast tradewinds reach their northernmost position, the NEC and ECC are bothintensified. Unlike the NEC and ECC, seasonal variations of the SECfollow the strength of the southeast trade winds, which are mostintense during the Southern Hemisphere winter. At the same season,the equatorial upwelling is also intensified.

A prominent oceanic feature in the eastern equatorial PacificOcean is the existence of a tongue of cool water. Wyrtki (1981)suggested, based on heat budgets, that most of the Equatorial PacificCool Tongue reflects shallow upwelling out of the upper portionsof the eastward-flowing Equatorial Undercurrent (>20°C water), al-though a portion could result from the advection off the easternboundary. Bryden and Brady (1985) emphasized eastward and up-ward flow along the outcropping isopycnals, with sources somewhatdeeper than those predicted by Wyrtki (1981). This implies that theCool Tongue reflects basin-scale thermocline and sea-level structure,rather than cross-isopycnal upwelling, in response to local winds.Toggweiler et al. (1991) argued that much of the SEC includes radio-carbon-depleted water that originates in the subantarctic Pacific.They believed that this water transits eastward in the lower part of theEquatorial Undercurrent (as 11°-14°C water) before upwelling offPeru and advecting westward into the SEC. At present, both radiocar-bon and heat budget considerations suggest that northward advectionof cool surface water in the eastern boundary current is not importantin setting the characteristics of water in the SEC of the Pacific Ocean.

Site 846, at 3°S, is probably far enough off the equator that it is notvery sensitive to true equatorial upwelling, which only occurs withina couple degrees of the equator (Wyrtki, 1981; Philander, 1990).Instead, it is probably sensitive to a combination of (1) westwardadvection of recently upwelled water off the eastern boundary and (2)outcropping of cool isopycnals associated with the intensities oflarge-scale tropical Pacific circulation.

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J. LE, A.C. MIX, NJ. SHACKLETON

20°-

15°-

10°

5 " •

n°•

5°S-

Calif. \Current

j •

—X

<— <—.. N. EcJ>Curreπt

\

N. Eq. Countercurrent

Eq. Undercurrent /* •

S. Eq. Current

1—

fI

* \>.-846\

π \_

1 ^ a

PeruCurrent '

"̂ \ à

"Si

11115°W 110° 100° 80°

Figure 1. Site location and generalized surface circulation system in theequatorial Pacific Ocean. Surface current shown as solid arrow and subsurfacecurrent as dashed arrows.

SAMPLE PREPARATION

A high-resolution sequence of samples covering the last 800 k.y.was spliced together from Holes 846B, 846C, and 846D on the basisof the composite depth (Shipboard Scientific Party, 1992). The com-posite sections were constructed by detailed correlation of the recordsof gamma-ray attenuation porosity evaluation (GRAPE) records,magnetic susceptibility, and reflectance spectroscopy of the sedi-ments from different holes at a resolution of 2 to 4 cm (Hagelberg etal., 1992). The average sampling interval for this foraminiferal studyis 10 cm, which yields an average time spacing of 3.6 k.y. per sample.

The sediment samples were processed using standard procedures(Imbrie and Kipp, 1971). All samples except those from Section 138-846B-2H-3 to -2H-4 and Section 846C-2H-2 to -2H-3 were processedat the Godwin Laboratory of the University of Cambridge. Sampleswere washed using distilled water through 150 µm sieves, then fine andcoarse fractions were dried in an oven at 60°C and weighed separately.The other set of samples was processed at Oregon State University. AtOSU, samples were first freeze-dried, washed through 125 µm sieves,and then dry-sieved through 150 µm sieves. Experiments with freeze-drying show that the fragmentation of foraminiferal tests does notchange. Observation of samples was performed in the >150 µm sizefraction. The coarse fraction was split using a Soiltest CL-242 A micro-splitter as many times as required to get a subsample of approximately300 whole foraminiferal specimens. All whole, or essentially whole,specimens in the final split were identified and counted following thetaxonomy used by the CLIMAP project (Kipp, 1976; CLIMAP, 1981).All benthic foraminifers were placed into one group, and the ratio ofbenthic foraminifers to the benthic plus planktonic foraminifers wascalculated. The number of fragments also was counted. A fragmenta-tion index is calculated as

Frag.Index =frag/8

100%.frag/8 + whole

The arbitrary number 8 is used to correct the nonlinearity inherentin the traditional calculation of fragmentation ratio, based on theobservation that a whole foraminifer is likely to be broken into anumber of fragments (Le and Shackleton, 1992). The traditionalcalculation of the fragmentation ratio, which divides the number offragments by the number of fragments plus whole foraminifers, isoversensitive to light dissolution and insensitive to severe dissolution.For isotope analysis, Cibicides wuellerstorfi was selected from the>150 µm size fraction. When there were not enough C. wuellerstorfiin a sample, Uvigerina peregrina was picked from the same sizefraction. Most of the U. peregrina samples were analyzed at the

Godwin Laboratory, University of Cambridge, using a VG IsotechPRISM mass spectrometer. The specimens were first cleaned using10% hydrogen peroxide and an ultrasonic bath, then reacted with100% orthophosphoric acid at 90°C using a VG Isocarb common acidbath system, and the released CO2 was analyzed. The results arereported in the international Pee Dee Belemnite (PDB) scale. Theanalytical precision was about ±0.06‰. The C. wuellerstorfi sampleswere analyzed at the College of Oceanography at Oregon State Uni-versity, using a Finnigan/MAT251 mass spectrometer. For detailedprocedure, refer to Mix et al. (this volume). The δ 1 8 θ data used in thisstudy is reported in Mix et al. (this volume).

RESULTS AND DISCUSSION

Oxygen Isotope Stratigraphy

The oxygen isotope data are plotted vs. revised composite depth(RMCD) (Hagelberg et al., this volume) in Figure 2. The compos-ite record was constructed by adding ±0.64‰ to the δ1 8θ valuesfrom C. wuellerstorfi to approximate the values from U. peregrina(Shackleton, 1974).

The age model was generated by correlating the composite recordto the SPECMAP time scale (Imbrie et al., 1984) for the periodyounger than 600 ka, and to the ODP Site 677 δ 1 8 θ time scale(Shackleton et al., 1990) for the older period. To merge these two datasets, we first scaled the SPECMAP record, which was reported invariance units, to the same mean and variance as the Site 677 benthicrecord over the period from 0 to 700 ka, and then spliced the tworecords at 600 ka, where there is a perfect match of δ 1 8 θ values.Correlation of the Site 846 benthic δ 1 8 θ record to this reference recordwas accomplished using the quantitative mapping function techniqueof Martinson et al. (1981). To avoid falsely correlating noise, we con-strained the correlation to produce sedimentation rates that varysmoothly, with no variations in sedimentation rate at periods shorterthan 20 k.y.

Figure 3 illustrates the Site 846 δ 1 8 θ time series, together with thetarget δ 1 8 θ time scale constructed from the SPECMAP and ODP Site677 for comparison. Note that the Site 846 δ 1 8 θ record has only onelightest value at stage 17, where Holes 846C and 846D were splicedtogether. The comparison of the GRAPE records of Holes 846B, 846C,and 846D suggests that sampling at stage 17 was not adequate. Thisinterval is in Section 138-846D-3H-1, which contains a large verticalburrow visible in the core photograph (Mayer, Pisias, Janecek, et al.,1992). It appears that stage 17 interval may be better represented inSection 138-846C-3H-2, although this would need to be confirmed byfurther isotopic analysis. Because of the incomplete stage 17, all thetime series analyses in this study use only the part of the time series thatis younger than 663 ka, where there is a core break.

Cross-spectral analysis techniques have been applied to study thevariance distribution in the frequency domain and phase relationshipsof various time series generated in this study (Jenkins and Watts,1968). The time series were first interpolated at 3 k.y. intervals andanalyses were performed on a series of 221 data points extending to663 ka. For cross-spectral analysis, 75 lags were used, giving a band-width of 0.006 cycle/k.y. The phase ranges were calculated at the 95%confidence level; and in the phase plot, the phase angle is only shownat those frequencies at which coherency is significant.

The cross-spectrum shows that the Site 846 δ 1 8 θ time series con-tains concentrated variance in bands centered at the 100, 41, and 23k.y. periods, and are highly coherent with target δ1 8θ records (Fig. 4).The two time series are in phase with each other (Table 1). Thissuggests that the Site 846 δ 1 8 θ record was successfully correlated tothe target δ'8O time scale.

Dissolution of Foraminifers

Fragmentation of planktonic foraminiferal shells is a reliable indi-cator of the dissolution level that a foraminiferal assemblage has

676

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3 -η

o 3 4-

<uex 5 -

0

LATE QUATERNARY PALEOCEANOGRAPHY, PACIFIC OCEAN

10 15

~T~

20~r25 30

Depth (rmcd)Figure 2. Site 846 δ 1 8 θ data plotted vs. rmcd. The composite δ 1 8 θ record was constructed by combining δ 1 8 θ data from different holes and by adding +0.64%eto the values of δ 1 8 θ from C. wuellerstorfi to approximate U. peregrina δ 1 8 θ.

3 -i

4 -

Target <

ODP* 46 018

PQ

o g5 -

0.4Age (Ma)

Figure 3. Site 846 δ 1 8 θ time series constructed by correlating to the SPECMAP δ l 8 θ time scale for the period younger than 600 ka and to the ODP Site 677 δ 1 8 θtime scale for the older period. Shaded areas represent glacials.

experienced (Thunell, 1976; Le and Shackleton, 1992). Figure 5Billustrates the variations of the fragmentation index at Site 846. Theaverage value of the fragmentation index is 9%, and the 95th percen-tile is 27%. Fragmentation is usually greater during interglacialstages, generally consistent with normal Pacific dissolution patterns(Berger, 1973; Le and Shackleton 1992). Especially strong fragmen-tation events are evident during the mid-Brunhes period between 250and 650 ka. At the most dissolved level at about 400 ka, as indicatedby the maximal fragmentation, the assemblages are composed mostlyof large specimens of N. dutertrei and G. menardii. The last twoHolocene samples are also highly fragmented, consistent with theHolocene dissolution event in the Pacific Ocean (Keir and Berger,1985). This late Holocene carbonate dissolution event is usually onlyseen in deep cores (Francois et al., 1990; Le and Shackleton, 1992).

The relative abundance of benthic foraminifers shows a fluctua-tion pattern similar to the fragmentation index at Site 846 (Fig. 5C).When there is little carbonate dissolution, the %benthics may beindicative of the productivity of overlying surface waters, becausebenthic foraminifers are more sensitive to changes in productivitythan are planktonic foraminifers (Berger and Diester-Haass, 1988;Herguera and Berger, 1991). On the other hand, benthic foraminifersare more resistant to carbonate dissolution than are planktonic fora-minifers, when carbonate dissolution becomes severe enough tolargely increase the original relative abundance of benthic foramin-ifers by dissolving a large number of planktonic foraminifers, theresultant %benthics may indicate dissolution, rather than productiv-ity. Although neither index is a strictly quantitative measure of car-bonate dissolution, the existence of a similar signal in both %benthicsand the fragmentation index is consistent with the stronger dissolu-tion events during interglacial intervals.

Table 1. Results of cross spectral analyses.

X-Y

δ l x 0 s p e c v s . δ l x 0 K 4 6

- δ ' 8 O x 4 6 vs. fragment-δ'xOs 4 f tvs. %benthics-δ l x 0 8 4 ( S vs. factor 1- δ ' 8 O a 4 6 vs. factor 2- δ l 8 0 a 4 f i vs. factor 3

100 k.y.

0

5±10-9±2315±20

-30+19160±17

k

0.980.890.92NC0.930.92

41 k.y

0

2±1113±27

-18±25

k

0.980.86NCNC0.88NC

23 k.y.

0 k

4+7 0.99NCNCNCNCNC

Notes: Time step used = 3 k.y., number of lags = 75, which gives a bandwidth of 0.006cycle/k.y. Phase ranges were calculated at 95% confidence levels. Positive angleimplies that X leads Y. NC = not coherent.

Cross-spectral analysis was performed between the - δ 1 8 θ andfragmentation index and %benthics to study their cyclicities andphase relationships. Results show that the power spectrum of frag-mentation time series is dominated by variance at the 100 k.y. eccen-tricity and 41 k.y. obliquity bands (coherency = 0.89, 0.86, respec-tively; Fig. 6A). The variance concentration at the 23 k.y. precessionband is also significant; it is, however, not coherent with - δ 1 8 θ at 80%confidence level. Fragmentation maxima are approximately in phasewith ice volume minima at the periods of 100 and 41 k.y.

The phase relationships between fragmentation and the global icevolume at Site 846 differ from those in the western equatorial PacificOcean. In a western Pacific core, RC17-177 (1°14.5'S, 157°00.5'E,2600 m water depth), fragmentation maxima significantly lag icevolume minima (77 ± 13° at 100 k.y., 85 ± 40° at 41 k.y., and 115 ±

677

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J. LE, A.C. MIX, N.J. SHACKLETON

>, 1 -i

sQ

ö. 0 -

i3

-1

••• ODP846-O18

— Target -O18

lOOk.y• 41 k.y*.

1.0 η

| 0.5 -

0.0 J

200 -i

Non-zero coherency at 80%

-200

•• Phase

•*• Confidence interval

0.00 0.02 0.04 0.06

Frequency (cycle/k.y.)

Figure 4. The cross spectrum between the SPECMAP and Site 846 δ 1 8 θ timeseries for the last 663 ka. The time step is 3 k.y., and 75 lags were used. Thephase ranges were calculated at 95% confidence level.

28° at 23 k.y. at the 95% confidence level). ERDC-93P (1619 m waterdepth) and V28-238 (3120 m water depth), which are adjacent toRC17-177, have phase relationships similar to those of RC17-177.Note that the seawater carbonate chemistry and productivity are dif-ferent in two areas. The lysocline progressively shoals to the east inresponse to greater organic carbon input associated with increasedsurface productivity. In the western equatorial Pacific Ocean, abovethe Ontong Java Plateau, the lysocline was mapped between 3400 m(Berger et al, 1982) and 3500 m (Valencia, 1977). In the easternequatorial Pacific Ocean, over the western flank of the East PacificRise, the lysocline lies at about 3200 m (Adelseck and Anderson,1978). Whether the differences in the phase relationships are causedby the fact that Site 846 is near the present lysocline in the area andthose western Pacific cores are above the lysocline remains to be seen.

The %benthics contains concentrated variance at the 100 k.y.eccentricity band (Fig. 6B). It leads ice volume minima by 15 ± 20°,thus is approximately in phase with ice volume minima. This phaserelationship is similar to that of fragmentation index at the 100 k.y.cycle. However, %benthics does not show significant variance at the41 k.y. tilt and 23 k.y. precession cycles; instead, it contains signifi-cant variance near periods of 46 and 33 k.y. The power spectrum sug-gests that the %benthics of Site 846 mainly responded to deep-seadissolution rate, but was also influenced by other factors, perhapsorganic carbon flux from surface waters.

Faunal Variations of Planktonic Foraminifers

A total of 239 samples were analyzed in terms of species composi-tions, with an average of 390 specimens per sample. The relativeabundance data of the planktonic foraminiferal species are listed in theAppendix. Table 2 contains the descriptive statistics of these species incomparison with the same species of those Pacific core-top samples

that are distributed to the east of 180° longitude (Prell, 1985). In Figure7, the variations of the relative abundances of the 10 most abundantspecies have been plotted vs. age. The time series of δ'8O and fragmen-tation index are also plotted in the top panel for comparison. Of these10 species, seven have average relative abundances above 2%. In theorder of decreasing average percentages, these are Neogloboquadrinadutertrei, Globigerina bulloides, Neogloboquadrina pachyderma(right-coiling), Globorotalia menárdü, Globigerinita glutinata, Glo-bigerinoides ruber, and Orbulina universa, together constituting ap-proximately 94% of the total planktonic foraminiferal census count.Overall, the relative abundances of these species fluctuate with greateramplitudes between 250 and 650 ka, the so-called mid-Brunhes disso-lution event, than during the last 200 k.y, probably as a result of strongcarbonate dissolution.

Together, N. dutertrei and dextral N. pachyderma account for 69%of the planktonic foraminifer census count, dominating the forami-niferal assemblages at Site 846 (Fig. 7A). N. dutertrei shows thegreatest downcore variations among all the species, as indicated by itsstandard deviation (Table 2). N. dutertrei and N. pachyderma (right-coiling) display large morphological variations in different parts of theoceans; a variety of transitional forms exist between typical specimensof N. dutertrei and N. pachyderma (right coiling) (Kennett, 1976). Torepresent those intermediate forms between N. dutertrei and dextral N.pachyderma, "P-D intergrade" was used in the CLIMAP project(Kipp, 1976; CLIMAP, 1976). However, separation of "P-D inter-grade" from N. dutertrei and dextral N. pachyderma has also beendifficult, and its use remains controversial. Because this taxon was notused in the Pacific core-top foraminifer identifications (Parker andBerger, 1971; Prell, 1985), this study only calculates the percentagesof N. dutertrei and dextral N. pachyderma. "P-D intergrade" waslumped into N. dutertrei, which therefore in this study includes thetypical large specimens of N. dutertrei and a large number of "P-Dintergrade." Observation of the compositions of N. dutertrei and N.pachyderma (right-coiling) shows noticeable variations through gla-cial and interglacial cycles resulting from dissolution and/or ecologicaleffects. The more dissolved interglacial samples tend to contain morelarge specimens of N. dutertrei, whereas better preserved glacial sam-ples tend to contain more small specimens. This phenomenon is mostevident as the low abundance of N. dutertrei and N. pachydermaduring the mid-Brunhes most dissolved period at about 400 ka, whenonly a small number of large specimens of this group remain. N.pachyderma tends to show higher abundances during glacials exceptstage 4.

G. menardii shows fluctuation patterns that are remarkably similarto both the fragmentation index and the δ 1 8 θ records (Fig. 7A). Thisspecies shows stronger positive correlation with the fragmentationindex than N. dutertrei, which is regarded as more dissolution-resistantthan G. menardii (Parker and Berger, 1971). This is because 'W.dutertrei" in this study contains a large proportion of small "P-Dintergrade," which is dissolution susceptible; as a result, "N. dutertrei"in this study becomes less dissolution-resistant as a whole group thanG. menardii. In the Pacific Ocean, maximal abundances of this speciesoccur in places where sea surface temperatures (SST) are between 26°to 28°C (Prell, 1985; Le, 1991). At Site 846, the present SST rangesfrom 21°C in September to 27°C in March (Halpern et al., 1990);therefore, higher abundances of G. menardii during interglacials prob-ably implies that SST was higher during interglacials than duringglacials. However, caution should be excercised, because the maximalabundances of this species during the mid-Brunhes dissolution periodsuggest that the abundance of G. menardii was also influenced bydissolution at Site 846. Note that if ecological factors produced moreG. menardii during interglacials than during glacials as a result ofhigher temperatures, dissolution and temperature would affect therelative abundances of G. menardii in the same direction, since disso-lution was stronger during interglacials.

G. ruber, G. sacculifer, and G. glutinata generally have abun-dances below 10% at Site 846. Although in low abundances, these

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0.0

Figure 5. Time series of fragmentation index (B), and %benthics (C). The %benthics is calculated as the number of benthic foraminifers divided by thenumber of benthic plus planktonic foraminifers. For the calculation of the fragmentation index, see text. The Site 846 δ 1 8 θ time series is plotted for comparison(A). The shaded areas represent glacial stages.

SSC<u

Q

Io

o

1

-

0 -

1 -

J \jt

lOOk.y.1 I

t • •••

41 k.y.

••• ODP846-O18

— Fragment Index

23 k.y. V

1 ' 1

ODP846-O18

%benthics

1.0

ü

o

u

J o - •

-200

Phase

Confidence interval

-200

Phase

Confidence interval

0.00 0.02 0.04

Frequency (cycle/k.y.)

0.06 0.00 0.02 0.04 0.06

Frequency (cycle/k.y.)

Figure 6. The cross spectrum between the time series of Site 846 -δ l 8 0 (A) and fragmentation and %benthics (B). The values of fragmentation index and %benthicshave been scaled so that their power spectra can be displayed on the scale as that of δ 1 8 θ. The parameters for cross spectral analyses are the same as those in Figure4. A positive phase angle indicates that ice volume minima lead fragmentation maxima. For numerical value of the phases and coherencies, see Table 1.

679

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J. LE, A.C. MIX, NJ. SHACKLETON

A 2 ^

of^ 4-

4 0 -

0 -

40 -i

| 2 0 -

0 J

40 η

20 -

0 -

10 - i

Id

o -^ 10

h

35 -

W

018

- 6 0.8

40 S

20ent

0.0 0.2 0.4 0.6 0.8

Age (Ma)

Figure 7. A, B. Relative abundances of 10 abundant planktonic foraminifers species at Site 846. The Site 846 δ 1 8 θ and fragmentation time series areplotted in the top panel for comparison. The shaded areas represent glacial stages.

species show systematic variation patterns with higher abundancesduring interglacials, thus having positive correlation with the fragmen-tation index (Figs. 7Aand 7B). This is surprising, because these speciesare especially sensitive to dissolution (Parker and Berger, 1971) andshould have been less abundant in more dissolved samples if dissolu-tion was the dominant control factor. However, the maximum abun-dances of these three species occur in the area where the winter SSTsare about between 25° and 28°C in the Pacific Ocean (Prell, 1985; Le,1991), whereas the present SST at Site 846 ranges from 21° in Septem-ber to 27°C in March (Halpern et al., 1990). Therefore, the higherabundance of these species during interglacial episodes may indicatewarmer, more subtropical conditions (consistent with CLIMAP1981).

In addition, since the rate of dissolution at the seafloor was greater dur-ing interglacial time, these fragile species would be under-representedin the sediment record relative to their upper ocean production, and wewould underestimate the extent of climate change. The above discus-sion suggests that the positive correlation between fragile planktonicspecies and fragmentation is fortuitous and driven by different pro-cesses (upper ocean warming bringing in warm species, deep oceanchemistry controlling dissolution rate).

Higher abundances of G. ruber, G. glutinata and G. sacculifer inthe interglacial samples raise the concern that the higher interglacialfragmentation may be caused by the greater fraction of fragile speciesreaching the seafloor. In this case, it is possible that there was no

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r-60018

Figure 7 (continued)Q O 0.2 0

Age (Ma)change in the deep-sea dissolution rate, and the apparent fragmenta-tion record would have been driven by upper-ocean ecology. How-ever, considering other evidence for wide-spread dissolution ininterglacial episodes in the Pacific Ocean (Farrell and Prell, 1989; Leand Shackleton, 1992), the generally low abundance of these speciesand our observation that G. ruber and G. sacculifer in interglacialsamples are more thick-walled, robust specimens that are more likelyto preserve well, we believe that changing dissolution rates in thedeep sea are at least part of the story.

G. bulloides averages approximately 12% with maximal values ofabout 29% (Fig. 7B). This species tends to show higher abundancesduring glacial periods than during interglacial periods; and in the lastHolocene sample, it has an abundance of 4.4%.

G. inflata shows several distinctive spikes during oxygen stageboundaries 3/2,4/3,17/16, and 18/17. This species was also abundantduring stage 2. Despite its maximal abundance reaching 40%, thisspecies was generally absent during most periods of the time understudy. This pattern was also found in other cores in the eastern equa-

torial Pacific Ocean (McKenna at el., this volume; A. Mix, unpubl.data). The reasons why G. inflata exhibits sudden abundance spikesduring some glacial-interglacial transitions and glacials, but notothers, need further investigation.

Q-mode Factor Analysis

To simplify the faunal variations at Site 846, Q-mode factor analy-sis was used. Q-mode factor analysis resolves each fossil assemblageinto a proportional combination of a smaller number of independentend-members (i.e., factors); each factor is in turn a linear combinationof input species. The importance of a factor in describing an assem-blage is indicated by a factor loading, and the importance of a speciesin a factor is indicated by a factor score. In studies such as CLIMAP,Q-mode factor analysis is first used to resolve Holocene fossil assem-blages into factors that are then calibrated against a modern oceanicvariable to establish a transfer function. Then, core samples repre-senting the geological past are reconstructed in terms of these modern

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Table 2. Descriptive statistics for planktonic foraminifers from Site 846 and from core-top samples in the eastern equato-rial Pacific Ocean.

Species names

Orbulina universaGlobigerinoides ruberGlobigerinoides tenellusGlobigerinoides saccutiferGlobigerinella aequilateralisGlobigerinella calidaGlobigerina bulloidesGlobigerina rubescensNeogloboquadrina pachyderma (R)Neogloboquadrina dutertreiGloboquadrina conglomerataPulleniatina obliquiloculataGloborotalia inflataGloborotalia crassaformisGloborotalia menardiiGloborotalia tumidaGlobigerinita glutinataFragmentation indexc/c Benthic foraminifers

Average

2.32.30.11.20.31.1

11.70.1

17.951.6

0.00.31.50.45.60.12.49.03.6

0-800 ka at Site 846

St. dev.

2.01.40.31.20.40.85.90.27.08.00.20.45.60.86.80.21.56.62.3

Min.

0.00.00.00.00.00.01.30.01.8

31.50.00.00.00.00.00.00.0

2.20.0

Max.

13.06.91.77.12.94.8

29.31.5

35.467.7

1.12.4

41.16.3

36.01.18.2

43.212.8

Core-top samples in the East Pacific (Prell, 1985)

Average

0.710.40.74.42.11.94.20.80.2

17.32.0

10.23.60.92.9

17.58.0

St. dev.

1.315.6

1.65.32.52.5

11.11.62.4

24.32.8

15.29.73.05.2

23.710.7

Min.

0.00.00.00.00.00.0().()0.00.00.00.00.00.00.00.00.00.0

Max.

14.074.7

8.225.213.915.260.412.139.495.016.768.087.026.750.098.041.4

factors, and the transfer function is used to estimate the value of theoceanic variable (Imbrie and Kipp, 1971; CLIMAP, 1981; Le, 1991).A reliable foraminiferal transfer function is yet to be developed forthe use in the east Pacific Ocean. Here, we focus on analyzing thefaunal variations at Site 846, and then we look for the sources ofinfluences on the Site 846 faunas from the modern fossil assemblagedistribution. If factors defined from downcore species counts yieldinterpretable ecological assemblages present in the modern core-topsamples, then this method points to watermass variations responsiblefor the past changes in fauna. We found this direct application offactor analysis to the Site 846 faunal data to be more interpretable thanthe more traditional projection of modern core-top faunal factors ontodowncore faunas.

Another difference in the use of Q-mode factor analysis in thisstudy is that the species abundances of Site 846 that are input to thefactor analysis are expressed in terms of the total observed rangeusing the following range transformation:

y=x _x '

wherex is the species percentage in a sample;xmin and xmax are the minimum and maximum percentages of the

species in the whole sample set; andy is the range-transformed species abundance that is then sub-

jected to Q-mode factor analysis.

The purpose of the range transformation is to give each speciesequal weight in the factor analysis. Experiments with the Q-modefactor analysis without range transformation have shown that mainfactors are dominated by N. dutertrei, as expected, and that the sys-tematic variations evident in less abundant species, such as G. ruber,G. sacculifer, and G. glutinata, are masked by the dominance of N.dutertrei. The use of range transformation resulted in better extractionof the systematic variations represented by these minor species, at thecost of some noise amplification. To minimize counting noise in therange-transformed data, we have excluded from the analysis the rarespecies that never reach 2% of the foraminiferal population in thedowncore record of Site 846.

Q-mode Factor Analysis of Site 846 Samples

The 14 most abundant species were used in the factor analysis(Table 3). The first three factors explain 85% of the total variance ofthe 239 samples. If a fourth factor is used, it would only explain addi-tional 2.9% of the total variance that are made up of N. pachyderma

(right-coiling), G. ruber, and G. crassaformis. Therefore, the firstthree factors are deemed to have extracted systematic variation pat-terns in Site 846 assemblages. Table 3 also lists the varimax factorscores that define the three factors. Figure 8 displays the temporalvariations of the factor loadings.

The first factor is a N. dutertrei-N. pachyderma factor and ex-plains 40.5% of the total variance (Fig. 8). The time series variationsof this factor principally reflect the abundance fluctuations of N.dutertrei and N. pachyderma, and do not show a consistent associa-tion with the δ 1 8 θ record throughout the last 800 k.y. During the mid-Brunhes period, when dissolution was particularly severe, the abun-dances of these two species appear to have been related to dissolution;therefore, the factor loadings may be indicative of dissolution duringthat period.

The second factor is a G. ruber-G. menardii factor, explaining24% of the total variance (Fig. 8). This factor also has relatively largescores on G. glutinata and G. sacculifer. As we argued earlier, G.ruber, G. sacculifer, and G. glutinata represent warm signals in Site846 faunas; therefore, the time series fluctuations of this factor alsorepresent warm signals. This factor shows higher loadings duringinterglacial periods than during glacial periods.

The third factor is a G. bulloides-N. pachyderma factor, andexplains 23% of the total variance (Fig. 8). This factor has higherloadings during glacials and lower loadings during interglacials, afluctuation pattern that is opposite to that of the second factor.

We caution that the variance explained by each factor in the aboveQ-mode factor analysis has lost its absolute sense, since range trans-formation was used to amplify the variabilities of minor species.

Modern Distribution of Site 846 Factors

To look for sources of the influences on the Site 846 faunas, weexamined the planktonic foraminiferal species distribution in the 294core-top samples distributed in the eastern Pacific Ocean (to the eastof 180° longitude) (Prell, 1985). Prell and Hays (1976) used matrixmultiplication to project downcore factors onto core-top foraminif-eral assemblages. In this study, however, the range transformation ofthe species abundances of the Site 846 samples necessitated a certainrange transformation of modern core-top assemblages, but we wereunable to find such a transformation that can not only be applied toboth downcore and core-top samples, but also allows us to extractsystematic downcore variations and to produce interpretable ecologi-cal assemblages in the core tops. As a result, we consider the distribu-tion of those species that have large weightings in a factor as a first-order approximation of the distribution of that factor, instead of usingmatrix multiplication. For each factor, a general boundary was drawn;

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F60.§- 4 0 §

- I- 2 0 a

. ml: er-G.menardii Factor

Age (Ma)

Figure 8. Temporal variations of the loadings of the three varimax factors resulted from Q-mode factor analysis of the Site 846 samples. The Site 846 δ 1 8 θ andfragmentation time series are plotted in the top panel for comparison. The shaded areas represent glacial stages.

this was done based on the presence of a high percentage of species,rather than detailed abundance variations.

The distribution of the first factor is approximated by the distribu-tion of N. dutertrei plus dextral N. pachyderma. In the foraminiferalcore-top assemblage data that is available to us, only three of 294samples have dextral N. pachyderma. Therefore, the distribution of thefirst factor is virtually that of N. dutertrei. The reason for the absenceof dextral N. pachyderma in the eastern Pacific foraminiferal data isprobably because the dextral form was simply not recognized as aseparate group. This factor is mainly distributed along the equator,approximately in the range between about 7°N and 6°S (Fig. 9A). Thedistribution approximately coincides with the area of "cool tongue" inthe eastern tropical Pacific Ocean, where there is a shallow thermoclineand rich nutrients in surface waters (Levitus et al., 1993). Factor 1 alsodominates three core-top samples off Chile, perhaps a result of theoffshore effects of upwelling in the Peru-Chile Current. Observationsbased on plankton tow and sediment trap data in the Panama Basinshow that N. dutertrei inhabits the thermocline; and when the thermo-cline shoals, the species flourishes (Thunell and Reynolds, 1984). Thisspecies is also abundant in offshore eastern boundary current waters ofthe Northern Hemisphere California Current (Bradshaw, 1959; Ortizand Mix, 1992), as well as in upwelling waters off Peru (Thiede, 1983)and cool waters associated with the equatorial divergence.

The loadings of factor 1 are usually higher during glacial thanduring interglacial episodes. An exception is the last glacial maximumabout 20 k.y. ago, when it was anomalously low. This could reflect theanomalously high abundance of G. inflata at that time, which acted

Table 3. Varimax factor scores resulting from Q-mode factor analysis ofSite 846 foraminiferal data.

Species

O. universaG. ruberG. sacculiferG. aequiiateralisG. calidaG. bulloidesN. pachyderma (R)N. dutertreiP. obliquiloculataG. inflataG. crassaformisG. menardiiG. tumidaG. glutinata

Variance (%)

Factor 1

0.02150.0240

-0.0133-0.02270.04110.03750.53490.8240

-0.0419-0.1264-0.0130-0.0523-0.0067-0.0969

40.5

Factor 2

0.15460.50940.37110.18680.2914

-0.1095-0.1053

0.14010.21860.00700.00810.44850.03010.4079

23.6

Factor 3

0.14880.0844

-0.07060.04470.07820.82190.3098

-0.18310.08160.23760.1144

-0.10370.06010.2493

21.2

to decrease the relative abundance of all the other species. Therefore,based on the dominant distribution of N. dutertrei in the easternequatorial "cool tongue," this factor may be indicative of shallowthermocline and rich nutrients. Note also that the abundance of N.dutertrei may have been affected by carbonate dissolution during themid-Brunhes strong dissolution period.

The second G. ruber-G. menardii factor also includes significantinfluence from G. sacculifer and G. glutinata. Therefore, the distri-bution of this factor is approximated by the sum of the percentages of

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J. LE, A.C. MIX, NJ. SHACKLETON

90

60 -

30 -

0 -i

30 -

60 -

90

N. dutertrei - N. pachyderma (R)

BFactor 2

G. ruber - G. menardii

180 150 120 90 60 180 150 120 90 60

90

60 "

30 "

0 "

30 "

60 -

Factor 3

bulloides - N. pachyderma (R)

90180 150 120 θO 60

Figure 9. Geographical distributions of the three downcore factors derived from the Site 846 faunas. The distributions are approximated bythe sum of the percentages of those species that have large factor scores in the core-top foraminiferal assemblages. A. Factor 1: N. dutertreiand dextrally coilingN. pachyderma. B. Factor 2: G. ruber, G. menardii, G. sacculifer, and G. glutinata. C. Factor 3: G. bulloides and dextrallycoiling N. pachyderma. Note that the hatchured area off the Peru coast is based on plankton data of Thiede (1983). The above boundarieswere drawn based on general presence of high percentages, rather than the detail.

these four species (Fig. 9B). As shown in the figure, this factor ismainly distributed in the subtropical waters off the equator and awayfrom the eastern boundary because of the high abundances of G.ruber and G. glutinata. A number of samples in the Panama Basin alsohave moderate values on this factor as a result of abundant G.menardii. In general, the second factor is distributed in the area ofwarm tropical-subtropical surface water. The modern distribution ofthis factor confirms our earlier inference based on its temporal vari-ation that this factor represents warm signals at Site 846.

The distribution of the third factor is represented by the sum of thepercentages of G. bulloides and dextral N. pachyderma (Fig. 9C).The distribution of the factor primarily indicates the distribution of G.bulloides because of the absence of dextrally coiling N. pachydermain the core-top samples. This factor is present in core tops underlyingcool temperate areas south of 30°S. This assemblage is also commonin the northeast Pacific and the California Current (Bradshaw, 1959;Ortiz and Mix, 1992). The downcore record of factor 3 appears to be

linked closely to abundance of G. bulloides, which is generally mostabundant during glacial episodes. This species is considered to bemainly distributed in temperate-subpolar regions, it is also abundantin upwelling regions (Be and Tolderlund, 1971; Thiede, 1983).Thiede (1983) showed that the concentrations of G. bulloides canreach 50% of the total living planktonic foraminifers off Peru in theregion that is affected by upwelling. Therefore, high glacial loadingsof factor 3 may result from offshore influence of strong coastalupwelling. However, it is also possible that G. bulloides was importedinto the area during glacial time by a stronger and colder northward-flowing eastern boundary current.

Cross-spectral analyses were performed to study the variancedistribution of these three factors in the frequency domain (Fig. 10).Table 1 tabulates the phase relationships of the factor loadings withthe - δ 1 8 θ time series and their coherencies at the 100,41, and 23 k.y.periods. Factor 1 shows a complicated power spectrum, containingvariance at bands near 88, 46, and 22 k.y.. This is probably because

684

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0.0 -

200 -i

LATE QUATERNARY PALEOCEANOGRAPHY, PACIFIC OCEAN

1 - i• • ODP846-O18

— Factor 2

••• ODP846-O18

— Factor 3

v V V v

-200

0.0 J

£ £ •• Phase 200 -j*•* *"* •- Confidence interval

V j w

-200

0.0 -1

Phase 2 0 0 πConfidence interval

••H.

£ — — »- 0

-200

^ -SPhasf ^ :**** •" Confidence interval

0.00 0.02 0.04

Frequency (cycle/ley.)

0.06 0.00 0.06 0.00 0.02 0.04

Frequency (cycle/k.y.)

0.060.02 0.04

Frequency (cycle/k.y.)

Figure 10. Cross spectra between the Site 846 -δ 1 8 θ and the time series of the three factors. The parameters for cross spectral analyses are the same asthose in Figure 4. A positive phase angle indicates that ice volume minima lead factor loading maxima. For numerical value, see Table 1.

this factor has signatures of both thermocline depth and dissolution.During the mid-Brunhes strong dissolution period, this factor hadabout three 100 k.y. cycles; while at the period younger than 300 ka,the fluctuation patterns were more complicated. Both factors 2 and 3have variance concentrated at the period of the 100 k.y. orbital eccen-tricity band. In this band, highest loadings of factor 2 lead ice volumeminima by 30 ± 19° (coherency = 0.93), and those of factor 3 lag icevolume maxima by 20 ± 20° (coherency = 0.92). Factor 2 also hassome concentration of variance at the orbital obliquity period of 41k.y. (lead - δ 1 8 θ by 18 ± 25°). Factor 3 does not contain variance ateither tilt or precession cycles, but instead has significant variancenear periods at 50 and 30 k.y..

We interpret the significant lead of subtropical factor 2 as evidencefor temperature changes in the South Equatorial Current leading icevolume, in agreement with evidence based on alkenone temperatureestimates from the central equatorial Pacific (Lyle et al., 1992). Thus,the early warming relative to ice volume variations is not restricted tothe equatorial divergence, but also is associated with large-scalestructure of the SEC and eastern Pacific thermocline. In its phase, thissignal at Site 846 is similar to that of the tropical Atlantic (Mclntyreet al., 1989; Imbrie et al,. 1989). However, the Pacific SEC lacks thestrong 23 k.y. signal of the tropical Atlantic Ocean, which is probablydriven by the strength of the African monsoon (Mix et al., 1986;Mclntyre et al, 1989; deMenocal et al., 1993).

SUMMARY AND CONCLUSIONS

Comparison of the data on planktonic foraminiferal faunas, frag-mentation index, benthic foraminiferal abundances, and benthicδ l 8 0 over the last 800 k.y. in Site 846 yields the following results:

1. A fragmentation index records the effects of carbonate disso-lution on the foraminiferal shells. The time series contains significantconcentrations of variance at the 100 k.y. eccentricity period and the41 k.y. obliquity period. At these periods, maximum fragmentationoccurs during interglacial extremes. Extreme fragmentation eventsoccur during the mid-Brunhes (especially near 400 ka) and in Holo-cene sediments.

2. Higher fragmentation is often associated with high abundanceof the dissolution-resistant species G. menardii, but also with the dis-

solution-sensitive warm-water species G. ruber, G. glutinata, and G.sacculifer. Greater influx of fragile species during warm intervals mayenhance fragmentation, but does not exclude the possibility that frag-mentation may reflect changes in dissolution rate at the seafloor. Therelatively high abundance of warm-water species during interglacialsmust indicate warmer and more subtropical upper-ocean conditions.

3. Benthic foraminiferal abundances resemble the fragmentationindex, but do not record extreme events in the mid-Brunhes. The timeseries contains significant variance at the 100 k.y. cycle with a phaserelationship similar to that of the fragmentation index. We suspect thatthey respond both to selective dissolution of planktonic foraminifersand to the flux of organic carbon flux to the seafloor, and thus cannotbe interpreted simply.

4. Downcore variations in foraminiferal faunas can be expressedas three orthogonal Q-mode factors. These are interpreted by map-ping the species that have large weightings on the factors on Pacificcore-top foraminiferal assemblages. The first, containing N. dutertreiand right-coiling N. pachyderma, may reflect a shallow thermoclineand nutrient rich waters in the eastern equatorial Pacific "cooltongue". The second, containing G. ruber, G. menardii, G. glutinata,and G. sacculifer, represents warm, subtropical waters. The third,dominated by G. bulloides, probably is associated with cold waterupwelling along the eastern boundary. It is also possible that G.bulloides was transported from high latitudes by a colder and strongereastern boundary current during glacial times.

5. Factor 1 does not vary consistently relative to glacial-inter-glacial cycles. This suggests multiple, sometimes competing causesfor variation of this factor, including upper ocean structure, produc-tivity, and dissolution. Both factors 2 and 3 vary, mostly antithetically,with a strong 100 k.y. rhythm. Warm conditions lead interglacialmaxima, and cold conditions are perhaps linked to advection of coldupwelled water off the Peru margin during glacial maxima, and pos-sibly a stronger eastern boundary current. Subtropical factor 2 alsocontains significant variance, coherent with δ1 8θ, at the 41 k.y. band(warmest episodes leading interglacial events by 18 ± 25°).

We conclude that the foraminiferal faunal signals at Site 846,although influenced by dissolution, are interpretable in terms of thechanging characteristics of upper ocean waters. Prior to and duringinterglacial periods, the area was considerably warmer and more sub-

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J. LE, A.C. MIX, NJ. SHACKLETON

tropical than at present; during glacial periods, the area was colderthan at present with greater upwelling and advection off the easternboundary, and possibly a stronger and colder Peru Current. The "coldtongue" associated with the South Equatorial Current may also havebeen stronger during glacial maxima.

ACKNOWLEDGMENTS

We are grateful to M. Hall and B. Rugh for running mass spec-trometers; D. Pate, J. Wilson, and A. Morey for sample processing.We thank S. Crowhurst and E. Tappa for reading the manuscript, andR.C. Thunell for helpful discussions. This work is supported by theNERC of Great Britain, and the NSF and USSAC in the United States.Thanks are also extended to the post-doctoral support of the Univer-sity of South Carolina.

REFERENCES*

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Le, J., and Shackleton, NJ., 1992. Carbonate dissolution fluctuations in thewestern equatorial Pacific during the late Quaternary. Paleoceanography,1:2\-A2.

Levitus, S., Conkright, M.E., Reid, J.L., Najjar, R.G., andMantyla, N.A., 1993.Distribution of nitrate phosphate, and silicate in the world oceans. Prog.Oceanogr., 31:245-273.

Lyle, M.W., Prahl, F.G., and Sparrow, M.A., 1992. Upwelling and productivitychanges inferred from temperature record in the central equatorial Pacific.Nature, 355:812-815.

Martinson, D.G., Menke, W., and Stoffa, RL., 1982. An inverse approach tosignal correlation. J. Geophys. Res., 87:4807-4818.

Mayer, L., Pisias, N., Janecek, T, et al., 1992. Proc. ODP, Init. Repts., 138(Pts. 1 and 2): College Station, TX (Ocean Drilling Program).

Mclntyre, A., Ruddiman, W.F., Karlin, K., and Mix, A.C, 1989. Surface waterresponse of the equatorial Atlantic Ocean to orbital forcing. Paleoceanog-raphy, 4:19-55.

Mix, A.C, Ruddiman, W.F., and Mclntyre, A., 1986. The late Quaternary pale-oceanography of the tropical Atlantic. 1: Spatial variability of annual meansea-surface temperatures, 0-20,000 years B.P. Paleoceanography, 1:43-66.

Ortiz, J.D., and Mix, A.C, 1992. The spacial distribution and seasonal succes-sion of planktonic foraminifera in the California Current off Oregon,September 1987-September 1988. In Summerhayes, CP., Prell, W.L., andEmeis, K.C. (Eds.), Upwelling Systems: Evolution Since the Early Mio-cene. Geol. Soc. Spec. Publ. London, 64:197-213.

Parker, F.L., and Berger, W.H., 1971. Faunal and solution patterns of plank-tonic Foraminifera in surface sediments of the South Pacific. Deep-SeaRes. Part A, 18:73-107.

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Prell, W.L., and Curry, W.B., 1981. Faunal and isotopic indices of monsoonalupwelling: western Arabian Sea. Oceanol. Acta, 4:91-98.

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Romine, K., 1982. Late Quaternary history of atmospheric and oceanic circu-lation in the eastern equatorial Pacific. Mar. Micropaleontol, 7:163-187.

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Shackleton, NJ., 1974. Attainment of isotopic equilibrium between oceanwater and the benthonic foraminifera genus Uvigerina: isotopic changesin the ocean during the last glacial. Les Meth. Quant, d'etude Var. dim.au Cours du Pleist., Coll. Int. C.N.R.S., 219:203-209.

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Shackleton, NJ., Berger, A., and Peltier, W.R., 1990. An alternative astronomi-cal calibration of the lower Pleistocene timescale based on ODP Site 677.Trans. R. Soc. Edinburgh, Earth Sci., 81:251-261.

Shipboard Scientific Party, 1992. Site 846. In Mayer, L., Pisias, N., Janecek,T., et al., 1992. Proc. ODP, Init. Repts., 138: College Station, TX (OceanDrilling Program), 265-333.

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Date of initial receipt: 3 March 1993Date of acceptance: 21 March 1994Ms 138SR-138

687

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J. LE, A.C. MIX, NJ. SHACKLETON

APPENDIX

Relative Abundance of Site 846 Foraminifers

Core, section.interval (cm)

846B-1H-846B-1H-846B-IH-846B-1H-846B-1H-846B-IH-846B-1H-846B-IH-846B-1H-846B-1H-846B-1H-846B-1H-846B-1H-

. 12

. 2 4,33. 4 3,53,63,73,88, 100, 113, 124, 133, 145

846B-1H-2, 9846B-1H-2, 19846B-1H-2, 29846B-1H-2, 37846B-1H-2, 48846B-1H-2. 57846B-1H-2, 68846B-1H-2, 78846B-1H-2, 88846B-1H-2, 97846B-1H-2, 109846B-1H-2, 117846B-1H-2, 128846B-1H-2, 137846B-1H-2, 146846B-lH-3,9846B-1H-3, 18846B-1H-3, 28846B-1H-3, 39846B-1H-3, 48846B-1H-3, 57846B-lH-3,67846B-1H-3, 78846B-1H-3, 88846B-1H-3, 98846B-1H-3, 108846B-IH-3, 118846D-1H-1, 128846B-1H-3, 118846D-1H-1, 137846B-1H-3, 128846D-1H-1, 146846B-1H-3, 138846D-1H-1, 148846D-1H-2, 8846D-1H-2, 18846D-1H-2, 28846D-1H-2, 38846D-1H-2, 48846D-1H-2, 78846D-1H-2, 88846D-1H-2, 98846D-IH-2, 108846D-1H-2, 118846D-1H-2, 128846D-1H-2, 138846D-1H-2, 148846D-1H-3, 8846D-1H-3, 18846D-1H-3, 28846D-1H-3, 38846D-1H-3.48846D-1H-3, 58846D-1H-3, 68846D-1H-3, 78846D-1H-3, 88846D-1H-3, 98846D-1H-3, 108846D-1H-3, 118846D-1H-3, 128846D-1H-3, 138846D-1H-3, 148846D-1H-4, 8846D-1H-4, 18846D-1H-4, 28846D-1H-4, 38846D-1H-4, 48846D-1H-4 . 5 8

Shipboard

compositedepth(mcd)

0.120.240.330.430.530.630.730.88

.00

.13

.23

.33

.44

.59

.68

.79

.87

.982.072 . 1 72.282.382.472.592.672.782.872.963.093.183.283.393.483.573.673.783.883.984.094.184.284.184.374.284.464.384.484.584.684.784.884.985.285.385.485.585.685.785.885.986.086.186.286.386.486.586.686.786.886.987.087.187.287.387.487.587.687.787.887.988.08

Revised

compositedepth

(rmcd)

0.120.240 330.430.530.630.730.88

.00

.1323

.33

.44

.54

.68

.79

.87

.982.072.172.282.382.472.592.672.782.872.963.093.183.283.393.483.573.673.783.883.984.114.204.294.324.374.434.464.544.664.784.905.015.125.225.525.625.725.825.926.026.136.236.336.436.536.636.726.826.917.007.107.187.277.367.457.547.627.717.797.887.968.038 .11

O. uni.

0.3.1

0 0.0

0 7.7

0.80.2

.24.35 64.10.93.85.70.73.54.81.83.61.30.51.62.20.72.20.70.50.6

.50.42.00.8

2.33.7

.20.00.80.6

.90.2

.30.01.01.21.21.01.10.80.53.10.90.50.32.32.00.40.60.8

.4

.10.81.21.31.51.10.80.80.01.71.24.23.82.1

.7

.00.8.6.8

3.3

G. rub

1.12.9I 71.73 i

0.50.60.91.82.01 20.50.21 62.41.73.51.10.72.23.51.02.31.92.41.31.60.70.82.30.80.40.81.80.80.01.91.01.20.81.91.44.10.82.92.82.02.82.83.24.14.75.53.13.03.22.52.22.90.80.71.41.01.61.32.11.91.13.00.61.41.51.02.41.21.74.21.71.94.02.2

G. ten.

0.00.00 30.50.30.00.00.00.00.00 00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.20.00.00.00.00.30.20.20.00.00.00.40.00.00.00.00.00.00.00.00.00.00.20.00.30.30.00.00.00.00.00.00.00.00.0

G. sac.

1.80.90 31.42 31.41.40.50.60.20 30.50.20.01.10.70.40.80.20.40.00.00.50.60.50.00.00.00.00.00.00.00.00.00.00.30.00.00.00.01.40.00.50.52.20.70.21.70.61.22.32.23.01.70.80.61.80.40.40.60.90.00.41.60.20.50.00.01.00.30.30.61.00.50.01.20.20.40.00.90.4

Species

G. aeq

0.50.00 81.20 30.20.00.50.30.40 00.50.00 30.70.30.20.30.70.40.20.30.70.90.00.00.00.00.00.00.00.00.60.00.80.00.00.50.00.61.40.01.00.81.00.71.01.41.10.80.00.30.70.70.31.00.00.00.20.20.00.00.00.00.00.00.20.00.00.00.30.30.00.00.01.00.20.40.20.70.0

G. «//.

0.50.00 31.00 31.20.60.50.90.00 30.50.71.31.11.40.60.31.10.90.41.60.72.51.41.30.50.71.21.10.80.4

0.20.41.11.00.32.61.21.10.00.51.61.60.50.51.00.01.12.40.52.51.61.91.61.90.90.80.40.80.41.11.20.00.21.01.10.81.00.60.00.60.30.51.52.41.20.00.90.90.7

G. bid.

4.46.3Q 5

13.717.714.916.221.415.09.4

10 98.7

11.516 216.019.418.118.621.620.216.517.713.827.328.920.922.517.013.515.314.316.624.416.116.312.216.813.313.810.115.414.95.7

14.213.713.614.19.4

14.911.610.513.127.223.225.421.414.611.813.916.818.410.615.98.8

24.329.323.220.212.612.518.623.514.221.811.614.517.010.09.39.9

15.2

G. rbs.

0.00.30.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.20.00.00.00.00.00.20.00.00.00.31.50.00.00.00.00.00.00.00.20.00.00.00.00.50.00.20.00.00.00.00.00.00.00.00.00.00.00.00.00.20.40.20.00.00.00.00.00.00.01.00.00.50.20.0

N. pa.

13.417.715.419.217.727.315.915.319.312.47.05.04.96.4

10.410.311.613.414.013.615.921.016.712.913.115.816.017.917.915.114.314.816.415.815.019.421.418.715.418.27.7

16.219.918.711.818.724.614.821.718.820.318.09.4

10.714.512.311.720.518.919.525.726.725.817.515.518.715.117.923.435.224.618.417.622.424.312.315.620.326.218.718.3

R N. dut.

66.162.664.750.545.844.339.837.245.741.143.931.540.339.950.354.653.15 1.949.347.950.551.254.543.948.950.948.853.848.038.055.261.150.157.454.654.850.954.162.861.560.055.753.551.057.248.951.662.646.344.746.542.739.553.140.444.259.254.552.761.248.153.551.664.154.142.051.552.950.549.350.350.157.942.953.558.755.561.056.352.255.2

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LATE QUATERNARY PALEOCEANOGRAPHY, PACIFIC OCEAN

APPENDIX (continued).

Core, section,interval (cm)

846D-1H-4, 68846D-1H-4, 78846D-1H-4, 88846D-1H-4, 98846D-1H-4, 108846D-1H-4, 118846D-1H-4, 128846D-IH-4, 138846D-1H-4, 148846D-1H-5, 8846D-1H-5, 18846D-1H-5, 28846D-1H-5, 38846D-1H-5, 48846D-1H-5, 58846D-1H-5, 68846D-1H-5, 78846D-1H-5, 88846D-lH-5,98846D-1H-5, 108846D-1H-5, 118846D-1H-5, 128846D-1H-5, 138846D-1H-5, 148846D-1H-6, 8846B-2H-3, 8846D-1H-6, 18846B-2H-3, 19846B-2H-3, 29846B-2H-3, 38846B-2H-3, 48846B-2H-3, 58846B-2H-3, 68846B-2H-3, 77846B-2H-3, 88846B-2H-3, 96846B-2H-3, 107846B-2H-3, 118846B-2H-3, 128846B-2H-3, 137846B-2H-3, 148846B-2H-4, 3846B-2H-4, 13846B-2H-4, 23846B-2H-4, 31846B-2H-4, 41846B-2H-4, 54846B-2H-4, 54846B-2H-4, 62846B-2H-4, 73846B-2H-4, 87846B-2H-4, 95846B-2H-4, 1068 4 6 B - 2 H - 4 , 117846B-2H-4, 126846B-2H-4, 136846B-2H-4, 144846C-2H-2, 58846C-2H-2, 68846C-2H-2, 78846C-2H-2, 88846C-2H-2, 98846C-2H-2, 108846C-2H-2, 118846C-2H-2, 128846C-2H-2, 138846C-2H-2, 148846C-2H-3, 8846C-2H-3, 18846C-2H-3, 28846C-2H-3, 38846C-2H-3, 48846C-2H-3, 58846C-2H-3, 68846C-2H-3, 78846C-2H-3, 8846D-2H-1,88846C-2H-3, 18846D-2H-1.98846D-2H-U28846D-2H-I.38846D-2H-1,48846D-2H-1.58

Shipboard

compositedepth(mcd)

8.188.288.388.488.588.688.788.888.989.089 . 1 8

9.289.389.489.589.689.789.889.98

10.0810.1810.2810.3810.4810.5810.6810.6810.7910.8910.9811.0811.1811.2811.3711.4811.5611.6711.7811.8811.9712.0812.1312.2312.3312.4112.5112.6412.6412.7212.8312.9713.0513.1613.2713.3613.4613.5413.6113.7113.8113.9114.0114.1114.2114.3114.4114.5114.6114.7114.8114.9115.0115.1115.2115.3115.4815.4115.5815.5115.6815.7815.8815.98

Revised

compositedepth(rmcd)

8.198.268.348.428.508.598.688.778.868.979.089.199.299.409.499.599.689.789.879.96

10.0610.1610.2710.3810.4910.5510.6110.7010.8911.0211.1211.2011.2811.3611.4811.5811.6911.8011.8811.9512.0312.0912.1912.3112.4212.5312.6512.6512.7212.8112.9613.0513.1813.2913.3713.4613.5413.6713.7813.8613.9213.9714.0314.0914.1814.2914.4514.5914.6914.7814.8614.9515.0515.1715.3115.4115.4615.5215.5615.6315.7415.8415.95

O. uni.

0.82.50.50.51.52.71.10.81.70.91.60.70.90.01.21.82.61.01.41.20.82.10.90.00.72.12.10.72.12.94.33.42.22.70.82.50.71.61.32.10.41.10.61.00.31.40.63.01.40.74.81.01.01.40.60.41.30.70.30.00.21.74.00.81.01.01.20.66.04.32.41.62.41.91.72.31.81.92.21.32.12.21.0

G. rub.

1.56.66.03.72.92.75.52.82.91.83.14.91.72.25.03.63.81.02.10.80.01.91.42.11.10.61.81.81.01.24.02.73.61.00.51.10.21.61.92.33.31.13.72.03.35.03.44.26.53.52.42.51.81.40.80.42.91.80.00.02.01.40.51.31.31.31.90.92.02.31.43.43.22.63.43.44.04.52.03.73.24.63.2

G. ten.

0.00.00.20.00.00.80.00.50.50.20.20.30.00.70.00.30.00.20.20.00.00.30.00.00.20.00.00.00.00.00.00.00.00.00.30.00.00.00.00.00.00.00.00.00.00.51.10.60.90.20.00.00.00.30.00.00.00.00.00.00.20.00.00.00.00.00.00.00.00.40.00.50.30.00.00.00.00.00.01.60.41.10.5

G. sac.

2.31.22.61.92.32.72.20.51.40.91.30.71.32.53.12.00.90.70.00.40.20.00.00.00.00.00.60.00.00.00.31.20.50.20.80.00.00.30.30.00.00.00.61.31.10.71.74.21.90.54.11.70.30.50.31.10.30.70.00.50.40.30.02.10.31.00.40.91.22.71.40.01.91.90.40.02.43.02.57.13.85.22.2

Species

G. aeq.

0.40.80.40.30.00.80.40.50.20.20.20.00.00.00.21.00.40.20.20.40.00.00.00.00.00.30.00.20.00.00.00.00.00.00.20.00.20.00.00.00.00.00.30.00.50.00.00.60.20.52.70.50.00.20.20.00.00.00.00.00.20.00.30.30.30.30.01.10.00.80.00.00.00.30.00.00.40.40.21.30.60.51.0

G. cal.

1.21.23.51.62.91.90.71.32.41.82.70.70.42.21.71.01.30.00.20.41.01.90.21.21.40.02.10.00.50.00.00.30.00.60.30.00.00.90.30.20.40.70.90.00.50.92.32.43.31.51.41.01.80.70.90.71.01.81.52.62.60.92.41.80.80.70.40.60.00.82.12.41.31.31.31.72.00.71.70.51.50.50.7

G. bul.

5.06.24.45.05.53.69.9

15.213.013.219.35.21.35.43.46.97.79.7

10.415.09.2

11.210.810.79.9

20.421.122.520.8

7.39.38.19.89.28.96.18.34.45.88.54.47.4

10.75.76.9

10.410.79.18.1

10.08.61.74.68.9

10.412.112.29.7

13.321.828.417.117.217.521.416.317.722.620.611.610.810.06.68.88.14.5

10.27.87.77.15.56.85.6

G. rbs.

0.00.00.00.00.00.20.40.30.20.00.20.00.00.00.00.00.20.00.20.00.20.00.00.00.20.00.00.00.30.00.80.20.00.00.00.00.20.00.30.2().()0.40.00.30.30.20.00.00.70.50.70.70.80.20.00.00.00.00.00.30.00.00.00.30.00.30.00.40.00.40.00.00.30.00.40.00.00.70.20.50.00.50.2

N. pa.

13.013.015.315.922.522.729.017.023.418.511.224.926.821.327.029.630.935.428.825.035.231.428.922.223.633.922.524.225.230.919.119.619.721.832.823.924.618.721.625.928.127.528.326.020.622.5

7.17.4

10.916.613.423.618.222.629.727.624.231.025.618.821.321.324.319.619.716.718.213.512.718.319.514.714.414.69.44.45.83.12.83.83.05.57.9

R N. dut.

67.356.353.755.648.450.439.854.645.249.447.452.461.758.249.243.247.047.851.648.950.047.354.858.057.648.846.257.957.163.367.570.968.67 1 . 7

64.374.175.580.873.867.369.668.160.264.472.858.952.552.749.853.457.275.780.272.470.367.366.262.168.960.348.864.656.664.462.468.768.461.559.760.562.964.267.072.162.350.355.842.939.537.040.338.142.4

Page 16: 33. Late Quaternary Paleoceanography in the Eastern Equatorial ...

J. LE, A.C. MIX, N.J. SHACKLETON

APPENDIX (continued).

Core, section.interval (cm)

846D-2H-1.68846D-2H-1.78846D-2H-I,88846D-2H-2, 8846D-2H-2, 18846D-2H-2, 28846D-2H-2, 38846D-2H-2, 48846D-2H-2, 58846D-2H-2, 68846D-2H-2, 78846D-2H-2, 88846D-2H-2, 98846D-2H-2, 108846D-2H-2, 118846D-2H-2, 128846D-2H-2, 138846D-2H-3, 8846D-2H-3, 18846D-2H-.3, 28846D-2H-3, 38846D-2H-3, 48846D-2H-3, 58846D-2H-3, 68846D-2H-3, 78846D-2H-3, 88846D-2H-3, 98846D-2H-3, 108846D-2H-4, 8846D-2H-4, 18846D-2H-4, 28846D-2H-4, 38846D-2H-4, 48846D-2H-4, 58846D-2H-4, 68846D-2H-4, 78846D-2H-4, 88846D-2H-4. 98846D-2H-4, 108846B-3H-2, 8846B-3H-2, 18846B-3H-2, 27846B-3H-2, 37846B-3H-2, 48846B-3H-2, 58846B-3H-2, 69846B-3H-2, 78846B-3H-2, 88846B-3H-2, 109846B-3H-2, 128846B-3H-2, 147846B-3H-3, 18846B-3H-3, 36846B-3H-3, 58846B-3H-3, 77846B-3H-3, 99846B-3H-3, 118846B-3H-3, 137846B-3H-4, 3846B-3H-4, 23846B-3H-4, 44846B-3H-4, 62846B-3H-4, 79846B-3H-4, 103846B-3H-4, 125846B-3H-4, 145846B-3H-5, 18846D-3H-1,48846D-3H-1,68846D-3H-1.88846D-3H-1, 108846D-3H-1, 128846D-3H-1, 148846D-3H-2, 18846D-3H-2, 48846B-1H-1, 12846B-1H-1,24846B-1H-1.33846B-1H-1.43846B-1H-1.53846B-1H-1.63846B-1H-1.73846B-1H-1.88

Shipboard

compositedepth(mcd)

16.0816.1716.2716.4016.5116.6016.7016.8116.9017.0117.1017.2017.3117.4017.5117.6017.7017.9018.0018.1018.2018.3018.4018.5018.6018.7018.8018.9019.0419.1419.2419.3519.4419.5419.6419.7419.8519.9420.0420.1320.2220.3120.4220.5320.6320.7420.8420.9321.1421.3321.5221.7321.9022.1322.3222.5422.7322.9223.0823.2823.4923.6723.8424.0824.3024.4924.7325.1725.3725.5825.7825.9826.1726.3726.67

0.120.240.330.430.530.630.730.88

Revised

compositedepth

(rmed)

16.0616.1616.2616.4016.5116.6016.7016.8216.9117.0217.1017.2017.3117.4017.5117.6017.7017.9017.9918.1018.2018.2918.4018.5018.6018.7018.8018.9019.0419.1419.2419.3519.4419.5419.6419.7419.8519.9420.0420.2720.3520.4220.5120.6020.7020.8120.9221.0421.3521.5621.6821.8321.9922.2622.4922.7122.8723.0223.1423.3023.4823.6523 8324.0824.3024.4824.7125.0725.3025.4225.4825.5425.6926.2126.46

0.120.240.330.430.530.630.73

O. uni.

1.10.63.11.61.85.22.64.34.04.52.23.02.42.45.84.15.19.53.7

13.07.25.63.53.53.93.03.88.75.14.72.12.01.6

4.94.53.33.11.73.21.61.72.01.52.81.81.51.73.32.36.25.71.42.35.83.01.23.03.91.32.31.89.85 42.94.25.3

10.27.95.23.39.63.24.24.73.50.30.60.30.20.30.20.00.0

G. rub.

3.54.52.61.11.11.52.41.83.01.31.6I.I0.70.92.20.60.42.32.01.41.70.91.51.00.91.24.02.03.81.22.62.74.03.56.35.43.13.13.83.23.12.31.31.80.81.81.52.41.71.22.23.52.33.72.56.93.03.94.72.82.02.33 41.34.43.53.74.36.44.33.82.94.22.31.30.80.60.00.00.30.20.00.2

G. ten.

0.71.70.40.80.00.20.00.00.00.30.00.00.00.00.00.00.40.40.00.00.00.20.00.00.00.00.00.00.00.00.00.00.00.20.30.20.00.40.30.00.00.00.00.00.00.00.00.00.00.00.00.00.30.00.20.00.90.60.20.20.60.30 30.00.20.00.00.20.81.70.80.60.70.30.40.80.00.30.01.72.8

16.216.2

G. sac.

4.02.83.91.90.80.92.00.81.10.30.31.92.41.62.20.91.11.60.70.80.81.10.70.50.91.83.51.41.42.92.61.73.21.43.42.61.02.44.51.51.72.01.30.40.50.30.20.91.00.53.84.91.91.12.52.34.33.22.11.40.61.01 20.30.41.81.42.22.81.70.41.46.01.51.30.00.00.00.00.30.00.00.0

Species

G. aeq.

0.50.60.40.00.00.20.00.00.00.00.00.01.71.40.40.00.00.00.00.00.0().()0.00.00.30.01.61.10.30.30.50.70.80.40.00.90.00.40.60.61.01.50.90.20.00.00.00.00.30.51.10.30.30.50.21.20.00.00.60.20.40.00">0.00.00.40.40.80.00.00.40.32.90.90.04.13.43.64.13.71.94.22.4

G. cat.

1.32.00.70.81.10.40.71.20.00.82.20.30.20.01.50.81.11.21.00.01.02.01.50.52.10.60.70.31.61.72.31.71.62.62.94.42.01.52.60.61.40.60.00.61.52.11.31.12.01.53.81.41.31.12.51.54.82.03.00.90.61.00.30.00.82.51.00.60.40.51.91.42.92.00.90.00.00.00.00.00.00.30.2

G. bul.

4.74.05.26.76.8

12.511.612.514.08.07.38.6

11.112.610.911.212.012.612.013.09.1

10.510.27.1

13.610.413.412.95.73.23.18.22.45.36.16.34.13.54.22.62.24.74.85.76.06.27.93.1

10.714.94.96.65.2

12.911.23.83.98.75.86.97.8

13.1P 716.410.316.515.116.28.47.15.46.3

10.015.416.53.32.31.14.32.71.92.83.5

G. rbs.

0.00.80.21.10.00.00.20.00.00.00.60.00.00.00.00.20.00.00.00.00.00.00.00.20.00.00.00.00.00.00.00.00.00.00.00.00.00.20.00.00.00.00.00.00.00.00.20.20.00.00.00.00.00.00.00.00.00.00.00.20.00.00.00.00.00.00.00.00.00.00.00.30.00.00.4

367350358417299422357425

N. pa.

13.38.77.3

12.814.315.117.312.619.217.519.220.415.816.719.615.915.39.29.6

12.413.817.424.020.321.320.6

3.21.87.48.36.1

10.49.36.75.56.77.8

12.79.7

16.018.720.023.825.432.323.422.120.320.516.515.514.915.919.512.615.93.1

12.118.625.727.728.224.615.812.416.124.920.318.912.726.127.813.123.334.932.119.29.27.48.67.2

14.513.3

R N. dut.

32.441.250.968.775.57 1 . 6

73.566.961.678.275.475.773.273.065.573.773.16 1 . 4

70.660.374.072.264.472.063.764.647.95 1 . 0

59.860.853.958.550.646.140.348.558.758.357.572.373.767.071.571.163.269.374.977.967.063.465.766.260.544.760.059.24 1 . 6

46.955.76 1 . 4

60.443.650.363.337.237.538.746.639.639.246.051.337.141.338.7

2.93.61.91.42.31.21.92.5

690

Page 17: 33. Late Quaternary Paleoceanography in the Eastern Equatorial ...

LATE QUATERNARY PALEOCEANOGRAPHY, PACIFIC OCEAN

APPENDIX (continued).

Core, section,interval (cm)

846B-1H-1, 100846B-1H-1, 113846B-1H-1, 124846B-1H-1, 133846B-IH-1, 145846B-1H-2, 9846B-1H-2, 19846B-1H-2, 29846B-1H-2, 37846B-1H-2, 48846B-1H-2, 57846B-1H-2, 68846B-1H-2, 78846B-1H-2, 88846B-1H-2, 97846B-1H-2, 109846B-1H-2, 117846B-1H-2, 128846B-1H-2, 137846B-1H-2, 146846B-lH-3,9846B-1H-3, 18846B-1H-3, 28846B-1H-3, 39846B-IH-3, 48846B-1H-3, 57846B-1H-3, 67846B-1H-3, 78846B-1H-3, 88846B-1H-3, 98846B-1H-3, 108846B-1H-3, 118846D-1H- , 128846B-1H-3, 118846D-1H-1, 137846B-1H-3, 128846D-1H-1, 146846B-1H-3, 138846D-1H- , 148846D-1H-2, 8846D-1H-2, 18846D-1H-2, 28846D-1H-2, 38846D-1H-2, 48846D-1H-2, 78846D-1H-2, 88846D-1H-2, 98846D-1H-2, 108846D-1H-2, 118846D-1H-2, 128846D-1H-2, 138846D-1H-2, 148846D-1H-3.8846D-1H-3, 18846D-1H-3, 28846D-1H-3, 38846D-lH-3,48846D-1H-3, 58846D-1H-3, 68846D-1H-3, 78846D-1H-3, 88846D-1H-3, 98846D-1H-3, 108846D-1H-3, 118846D-1H-3, 128846D-1H-3, 138846D-1H-3, 148846D-1H-4, 8846D-1H-4, 18846D-1H-4, 28846D-1H-4, 38846D-1H-4, 48846D-1H-4, 58846D-1H-4, 68846D-1H-4, 78846D-1H-4, 88846D-1H-4, 98846D-1H-4, 108846D-1H-4, 118846D-1H-4, 128846D-1H-4, 138846D-1H-4, 148846D-1H-5, 8

Shipboard

compositedepth(mcd)

.00

.13

.23

.33

.44

.59

.68

.79

.87

.982.072.172.282.382.472.592.672.782.872.963.093.183.283.393.483.573.673.783.883.984.094.184.284.184.374.284.464.384.484.584.684.784.884.985.285.385.485.585.685.785.885.986.086.186.286.386.486.586.686.786.886.987.087.187.287.387.487.587.687.787.887.988.088.188.288.388.488.588.688.788.888.98

Revised

compositedepth(rmcd)

.00

.13

.23

.33

.44

.59

.68

.79

.87

.982.072.172.282.382.472.592.672.782.872.963.093.183.283.393.483.573.673.783.883.984.114.204.294.324.374.434.464.544.664.784.905.015.125.225.525.625.725.825.926.026.136.236.336.436.536.636.726.826.917.007.107.187.277.367.457.547.627.717.797.887.968.038.118.198.268.348.428.508.598.688.778.865.97

O. uni.

0.00.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.50.00.00.00.00.00.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.90.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

G. rub.

0.30.40.00.00.20.00.00.00.20.00.00.00.00.00.00.00.00.00.00.20.20.00.40.20.20.00.40.70.00.00.00.00.50.20.81.10.20.70.50.30.60.81.40.01.60.50.80.60.50.40.00.00.40.00.60.00.60.80.20.00.40.00.70.30.30.00.00.50.00.00.20.90.20.00.00.01.10.00.00.40.00.00.0

G. ten.

9.523.623.341.135.425.47.54.90.40.00.00.00.00.00.00.00.01.30.51.5

14.720.69.50.40.00.40.00.00.00.00.00.00.00.00.00.00.00.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

G. sac.

0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.40.00.00.00.00.00.00.00.00.00.00.00.00.00.30.00.00.00.00.00.00.00.00.00.00.00.00.00.01.41.01.11.43.12.11.30.70.40.40.20.30.40.00.00.00.30.30.30.00.00.00.20.00.20.00.20.00.00.00.00.00.00.00.00.50.2

Species

G. aeq.

3.12.52.52.72.91.62.63.13.44.84.73.11.82.32.83.40.71.33.33.00.61.91.62.03.22.93.83.13.15.12.84.26.16.67.58.34.38.01.72.46.610.06.84.43.76.26.06.24.34.54.51.92.01.41.72.41.00.83.03.44.30.61.01.81.91.72.72.71.72.92.37.73.37.78.79.512.210.28.06.64.75.69.3

G. cal.

0.00.40.00.50.00.00.00.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.40.40.40.80.70.00.00.00.00.00.00.30.00.20.20.00.00.60.00.90.00.00.00.00.00.00.00.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.20.0

G. bul.

1.51.34.73.71.62.21.51.73.73.75.07.27.33.64.73.42.21.83.13.71.82.31.61.31.21.82.32.71.90.52.02.20.93.12.61.33.41.91.52.12.24.84.57.56.02.94.13.20.72.42.01.90.72.50.62.40.62.31.51.92.20.60.00.01.32.92.12.91.52.10.01.81.10.42.92.71.92.92.13.31.02.72.5

G. rbs.

3264453222194433154552S8536377444223455384427322415225426406498262252458501273263294321195247358214423387373416426404288181249220320434583366308444508489475554283516249522389470263506335290327310417337414405241432454547259241548378344523273387414440

N. pa. R

15.711.111.811.09.611.08.88.37.39.911.09.210.38.85.83.63.38.26.68.26.06.17.38.29.34.811.713.611.012.811.421.617.022.514.420.714.918.17.311.413.811.914.313.78.36.94.55.33.94.05.44.23.52.72.63.22.74.43.64.16.13.33.23.62.74.24.85.14.65.12.55.63.46.95.07.29.66.56.17.23.84.5

N. dut.

3.82.23.03.53.7.93.41.72.2.66.95.11.93.0.2.2.42.23.86.75.96.15.65.03.1.43.33.64.54.43.19.47.47.64.77.48.46.63.83.74.71.63.13.32.32.51.91.90.9.72.22.10.01.41.51.21.11.31.52.28.02.61.73.83.72.33.73.74.95.53.18.32.77.85.16.54.82.30.98.73.55.37.9

691

Page 18: 33. Late Quaternary Paleoceanography in the Eastern Equatorial ...

J. LE, A.C. MIX, N.J. SHACKLETON

APPENDIX (continued).

Core, section.interval (cm)

846D-1H-5, 18846D-IH-5. 28846D-1H-5, 38846D-1H-5.48846D-1H-5. 58846D-1H-5, 68846D-1H-5, 78846D-1H-5, 88846D-1H-5. 98846D-1H-5, 108846D-1H-5, 118846D-1H-5, 128846D-1H-5. 138846D-1H-5, 148846D-IH-6. 8846B-2H-3. 8846D-IH-6. 18846B-2H-3, 19846B-2H-3. 29846B-2H-3, 38846B-2H-3. 48846B-2H-3, 58846B-2H-3, 68846B-2H-3. 77846B-2H-3, 88846B-2H-3. 96846B-2H-3, 107846B-2H-3, 118846B-2H-3, 128846B-2H-3, 137846B-2H-3, 148846B-2H-4, 3846B-2H-4, 13846B-2H-4, 23846B-2H-4, 31846B-2H-4, 41846B-2H-4. 54846B-2H-4, 54846B-2H-4. 62846B-2H-4, 73846B-2H-4. 87846B-2H-4, 95846B-2H-4, 106846B-2H-4, 117846B-2H-4, 126846B-2H-4. 136846B-2H-4, 144846C-2H-2, 58846C-2H-2, 68846C-2H-2, 78846C-2H-2, 88846C-2H-2, 98846C-2H-2, 108846C-2H-2. 118846C-2H-2, 128846C-2H-2. 138846C-2H-2. 48846C-2H-3. 8846C-2H-3, 18846C-2H-3, 28846C-2H-3. 38846C-2H-3, 48846C-2H-3, 58846C-2H-3, 68846C-2H-3, 78846C-2H-3, 8846D-2H-1.88846C-2H-3, 18846D-2H-846D-2H-846D-2H-846D-2H-846D-2H-846D-2H-846D-2H-846D-2H-

,98.28,38,48.58,68. 78.88

846D-2H-2. 8846D-2H-2. 18846D-2H-2. 28846D-2H-2. 38846D-2H-2, 48846D-2H-2, 58846D-2H-: . 68

Shipboard

compositedepth(mcd)

9.189.289.389.489.589.689.789.889.9810.0810.1810.2810.3810.4810.5810.6810.6810.7910.8910.9811.0811.1811.2811.3711.4811.5611.6711.7811.8811.9712.0812.1312.2312.3312.4112.5112.6412.6412.7212.8312.9713.0513.1613.2713.3613.4613.5413.6113.7113.8113.9114.0114.1114.2114.3114.4114.5114.6114.7114.8114.9115.0115.1115.2115.3115.4815.4115.5815.5115.6815.7815.8815.9816.0816.1716.2716.4016.5116.6016.7016.8116.9017.01

Revised

compositedepth(rmed)

9.089.199.299.409.499.599.689.789.879.9610.0610.1610.2710.3810.4910.5510.6110.7010.8911.0211.1211.2011.2811.3611.4811.5811.6911.8011.8811.9512.0312.0912.1912.3112.4212.5312.6512.6512.7212.8112.9613.0513.1813.2913.3713.4613.5413.6713.7813.8613.9213.9714.0314.0914.1814.2914.4514.5914.6914.7814.8614.9515.0515.1715.3115.4115.4615.5215.5615.6315.7415.8415.9516.0616.1616.2616.4016.5116.6016.7016.8216.9117.02

O. uni.

0.0().()0.20.00.20 00.00.00.00 00.00.00.00.00.00.00.00.00.00.00.00.0().()0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.50.00.00.0000.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.10.01.1().()0.30.20.50.80.40.00.0().()0.0().()0.00.0

G. rub.

0.70.00.20.00.20 30.40.00.00 00.00.00.50.00.20.00.30.00.00.00.00.00.30.20.00.00.00.00.00.00.00.40.61.30.30.0().()0.61.61.22.10.20 10.20.00.01.00.00.00.30.20.00.00.00.30.30.40.40.41.20.70.50.80.01.70.00.20.00.20.80.21.10.20.51.11.70.30.30.00.20.00.00.3

G. ten.

0.00.00.00.00.00 0().()0.00.00 00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0().()0.00.0().()0.00.00.00.00.00.00.00.00.00.00.00 00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0().()0.00.00.00.0

G. sac.

0.70.00.00.00.03 61.11.01.92 81.02.10.71.81.60.01.80.00.00.00.00.01.10.20.00.70.40.30.00.00.00.00.30.00.30.20.60.01.40.70.7().()0 30.20.00.00.00.00.30.00.40.00.00.30.00.30.20.00.00.00.00.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Species

G. aeq

9.38.73.56.14.62.82.02.21.6471.81.30.93.01.81.20.61.62.32.13.22.93.03.12.12.23.13.55.82.12.62.82.14.73.64.119.212.111.610.06.21.70 "i2.10.60.90.61.10.30.30.00.00.50.50.30.00.42.11.60.83.55.05.93.2

14.032.217.328.436.024.935.728.929.830.126.020.57.23.41.50.74.10.30.8

G. cat.

0.00.00.00.00.00 00.00.00.00 00.00.00.00.00.00.00.00.00.0().()0.00.00.00.20.00.40.20.00.00.20.40.00.00.00.00.00.00.00.00.00.00.00 00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.40.70.30.00.00.00.00.00.00.00.30.41.10.00.00.00.00.00.00.00.00.00.00.0

G. bid.

0.90.31.11.42.9181.60.20.70 40.40.00.90.30.91.20.61.10.50.60.81.41.60.80.81.11.30.31.60.90.41.81.52.01.62.32.34.84.06.72.72.01 00.90.51.30.30.90.92.11.80.91.90.81.02.00.71.31.64.71.73.22.11.32.11.72.94.94.08.22.72.53.74.94.83.93.51.10.71.52.51.90.0

G. rbs.

450286462278417394548411425253513376436328443338336449389518375592366480608278458317313437270282327298364443177165430401292403389576637446311331331385504345378382388300566468248258286380376308236177450268403378524367410549354458374380542588510372377

N. pa.

4.65.63.74.34.93.83.42.72.53 63.32.93.23.54.85.04.14.57.97.47.08.17.98.14.34.84.56.28.86.07.35.55.77.99.515.122.626.321.210.44.05.56.64.94.54.04.05.75.77.37.17.18.04.910.07.43.510.77.313.913.811.01 1.913.022.837.421.343.233.226.324.523.926.821.922.512.37.05.33.93.25.06.24.1

R N. dm.

7.06.54.52.52.63.01.61.41.62 71.3.81.83.86.16.16.72.27.23.26.93.74.25.51.32.82.33.65.43.15.93.43.85.43.46.56.87.35.92.21.01.932.7

.52.52.42.43.30.80.9.60.84.72.6.66.62.43.47.72.85.53.44.810.29.84.36.73.87.35.47.75.24.63.8.3.0.1.0.5.1.0

Page 19: 33. Late Quaternary Paleoceanography in the Eastern Equatorial ...

LATE QUATERNARY PALEOCEANOGRAPHY, PACIFIC OCEAN

APPENDIX (continued).

Core, section,interval (cm)

846D-2H-2, 78846D-2H-2, 88846D-2H-2, 98846D-2H-2, 108846D-2H-2, 118846D-2H-2, 128846D-2H-2, 138846D-2H-3, 8846D-2H-3, 18846D-2H-3, 28846D-2H-3, 38846D-2H-3, 48846D-2H-3, 58846D-2H-3, 68846D-2H-3, 78846D-2H-3, 88846D-2H-3, 98846D-2H-3, 108846D-2H-4, 8846D-2H-4, 18846D-2H-4, 28846D-2H-4, 38846D-2H-4, 48846D-2H-4, 58846D-2H-4, 68846D-2H-4, 78846D-2H-4, 88846D-2H-4, 98846D-2H-4, 108846B-3H-2, 8846B-3H-2, 18846B-3H-2, 27846B-3H-2, 37846B-3H-2, 48846B-3H-2, 58846B-3H-2, 69846B-3H-2, 78846B-3H-2, 88846B-3H-2, 109846B-3H-2, 128846B-3H-2, 147846B-3H-3, 18846B-3H-3, 36846B-3H-3, 58846B-3H-3, 77846B-3H-3, 99846B-3H-3, 118846B-3H-3, 137846B-3H-4, 3846B-3H-4. 23846B-3H-4, 44846B-3H-4. 62846B-3H-4, 79846B-3H-4, 103846B-3H-4, 125846B-3H-4, 145846B-3H-5, 18846D-3H-1,48846D-3H-1,68846D-3H-1.88846D-3H-1, 108846D-3H-1, 128846D-3H-1, 148846D-3H-2, 18846D-3H-2, 48

Shipboard

compositedepth(mcd)

17.1017.2017.3117.4017.5117.6017.7017.9018.0018.1018.2018.3018.4018.5018.6018.7018.8018.9019.0419.1419.2419.3519.4419.5419.6419.7419.8519.9420.0420.1320.2220.3120.4220.5320.6320.7420.8420.9321.1421.3321.5221.7321.9022.1322.3222.5422.7322.9223.0823.2823.4923.6723.8424.0824.3024.4924.7325.1725.3725.5825.7825.9826.1726.3726.67

Revised

compositedepth(rmcd)

17.1017.2017.3117.4017.5117.6017.7017.9017.9918.1018.2018.2918.4018.5018.6018.7018.8018.9019.0419.1419.2419.3519.4419.5419.6419.7419.8519.9420.0420.2720.3520.4220.5120.6020.7020.8120.9221.0421.3521.5621.6821.8321.9922.2622.4922.7122.8723.0223.1423.3023.4823.6523.8324.0824.3024.4824.7125.0725.3025.4225.4825.5425.6926.2126.46

O. uni.

0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.50.50.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.30.00.30.20.00.00.20.00.20.00.30.20.00.00.00.00.00.00.00.00.00.00.00.0

G. rub.

0.00.50.20.20.00.30.00.40.00.00.00.20.20.0().()0.00.00.30.20.60.00.00.40.41.6().()0.01.10.00.30.00.00.90.00.00.30.00.00.30.00.00.70.60.50.40.01.30.82.41.20.40.00.71.00.61.10.20.40.00.00.80.31.11.21.3

G. ten.

0.00.00.00.00.0().()0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

27.813.71.60.012.824.66.54.00.00.30.4

G. sac.

0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.32.60.20.00.00.00.00.0().()0.00.00.00.00.20.00.00.00.0().()0.00.20.00.00.06.35.10.80.00.20.00.22.13.92.73.21.32.51.61.60.41.40.80.01.60.00.0

Species

G. aeq.

0.31.32.40.91.51.61.84.32.72.51.72.02.03.72.46.917.115.113.215.119.414.223.722.621.818.315.712.412.18.93.63.23.52.01.00.61.71.82.02.75.17.79.74.23.97.7

28.615.68.64.81.81.82.02.33.11.12.20.85.24.30.83.210.26.71.7

G. cal.

0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0().()0.00.00.00.00.00.00.00.00.00.00.00.00.0

G. bid.

1.60.51.01.01.50.60.73.92.73.71.92.22.21.70.92.25.95.02.72.03.62.72.05.55.82.64.15.24.51.92.74.71.71.21.81.81.71.32.03.00.81.44.92.93.54.61.75.55.43.04.12.13.71.91.73.24.33.82.44.31.94.04.94.71.3

G. rbs.

317371414578275635275485408353515449548574331492426357630344386402249508380427293458313617414342460509601339471453300402370287309380570260231507467568512388591311478285489494250423261347450344230

N. pa. R

3.66.24.44.24.34.54.53.55.93.42.22.83.13.43.74.514.414.717.120.521.510.917.915.416.014.513.319.014.210.46.56.35.14.24.03.22.72.87.35.86.516.820.57.510.211.613.920.16.95.85.33.84.87.67.17.44.54.710.49.211.38.112.97.27.4

TV. dul.

0.61.61.40.71.11.92.11.21.20.80.21.31.31.02.41.43.46.58.24.72.33.82.73.66.26.85.56.05.71.92.41.71.51.51.21.20.81.13.54.14.68.03.14.85.05.112.84.00.82.11.52.02.36.93.43.71.66.89.75.85.43.65.95.88.0

693