23. THE INORGANIC GEOCHEMICAL RECORD OF THE ......racy for major and minor elements. Element Si Al...

Prell, W. L., Niitsuma, N., et al , 1991Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 117

23. THE INORGANIC GEOCHEMICAL RECORD OF THE NORTHWEST ARABIAN SEA:A HISTORY OF PRODUCTIVITY VARIATION OVER THE LAST 400 K.Y.

FROM SITES 722 AND 7241

Graham B. Shimmield2 and Stephen R. Mowbray2

ABSTRACT

High-resolution sampling from late Pleistocene (last 400 k.y.) sediments of Site 722 (upper 16 m) and Site 724 (upper70 m), and subsequent inorganic geochemical analysis, has defined the history of productivity in the northwest ArabianSea. Eolian dust input from the Arabian Peninsula and Somalia is characterized by the record of Ti/Al and Cr/Al. Thisdust record displays strong precessional periodicity (cycles at 25 k.y.) suggesting the Southwest Monsoon and associatedwinds play a key role in transporting terrigenous material from the land. High biological productivity results in the ac-cumulation of biogenic CaCO3 and opal in the sediments, the latter having an unexpectedly minor contribution to thetotal mass flux. Due to dilution of the CaCO3 record by the terrigenous component, the record of biological productiv-ity is best exemplified by Ba. Its record, together with that of other metals recording biological association and redoxvariability (Cu, Ni, Zn, V, U) clearly identifies the interglacial episodes as being more biologically productive. The strik-ing agreement between Ba and the δ 1 8 θ record in planktonic foraminifers suggests that the supply of nutrients duringthese periods of high productivity is linked to ocean-wide changes in ocean fertility, and not just local upwelling condi-tions. High levels of phosphate accumulation in interglacial sediments is attributed to both diagenetic phosphorite for-mation and biogenic skeletal debris. This study provides a detailed record of productivity variation in the northwestArabian Sea during the late Pleistocene.

INTRODUCTION

The northwest Arabian Sea has been long known as an areaof active oceanic upwelling, brought about by the seasonal South-west Monsoon (Sen Gupta et al., 1975; Rao and Jayaraman,1970; Qasim, 1982; Slater and Kroopnick, 1984). The intensityof this wind induces Ekman transport of surface waters in thesummer months and sustains high levels of biological produc-tivity through nutrient supply from intermediate water depths.Microbial decay of the settling organic matter creates an intenseoxygen minimum zone (OMZ) between depths of 200 and 1500 m.

As significant variations in the climate of the Earth have oc-curred during the late Pleistocene (CLIMAP, 1976), and theSouthwest Monsoon is believed to have been strongly influencedby glacial/interglacial episodes (Prell, 1984a; Prell and Kutz-bach, 1987), it is likely that the sediments underlying the upwell-ing zone will record the history of the productivity variationsdriven by the Southwest Monsoon. Previous studies have used"proxy-indicators" such as the distribution of pollen types andthe percentage of G. bulloides in sediment cores to elucidate thehistory of upwelling (Van Campo et al., 1982; Prell, 1984a, b;Prell and Van Campo, 1986) with some success. However, inor-ganic geochemistry as applied to paleoceanography and climatechange pioneered in the Pacific (Adelseck and Anderson, 1978;Pedersen, 1983; Lyle et al., 1988; Pedersen et al., 1988; Finneyet al., 1988) has not been applied to the northwest Indian Ocean.Surface sediment geochemistry of this area (Kolla et al., 1981;Shankar et al., 1987; Shimmield et al., 1990) has provided ageochemical framework delineating the importance of terrige-nous dust inputs together with skeletal CaCO3 and minor opalaccumulation in this area.

In this study we have selected two sites from the Oman Mar-gin and performed a high-resolution study of the inorganic geo-

1 Prell, W. L., Niitsuma, N., et al., 1991. Proc. ODP, Sci. Results, 117: Col-lege Station, TX (Ocean Drilling Program).

2 The Department of Geology and Geophysics, University of Edinburgh, WestMains Road, Edinburgh, EH9 3JW, Scotland, U.K.

chemistry recorded in the sediments accumulating over the past400,000 yr. By using simple statistical treatment (principal com-ponent analysis) of the data we are able to define four majorfactors accounting for 80*70-95% of the geochemical variationobserved. Interpretation of the depth profiles of key elements,together with spectral analysis (see Weedon and Shimmield, thisvolume) allows an assessment of the significance of the South-west Monsoon and changes in global climate in influencing thehistory of upwelling productivity.

SAMPLING AND METHODS

Two sites were selected for this high-resolution study of theinorganic chemical composition of late Pleistocene sediments.These represent depositional conditions on the Owen Ridge be-low the present position of the OMZ (Site 722) in 2028 m of wa-ter, and within the OMZ on the Oman continental margin (Site724) in 593 m of water (Fig. 1). At both sites only the upper (I)lithologic unit was sampled which was composed of foramini-fer-bearing nannofossil ooze (5%-25% foraminifers) at Site 722,and calcareous clayey silt with 5°7o+ foraminifers at Site 724.Over the depth intervals studied here (0-15 mbsf, Hole 722B; 0-68 mbsf, Hole 724C), the sedimentary sequence is essentiallyhomogeneous with respect to mineralogical composition and sed-imentary structures. No evidence of slumped horizons, or massflow deposits are noted (Shipboard Scientific Party, 1989a, b)and the units sampled were undisturbed by gas expansion voids.

On vertical sectioning of the cores, 20 cm3 plugs were takenat 20 cm intervals from both holes, and sealed in polyethylenebags. On arrival at Edinburgh the samples were stored at 4°Cprior to processing. Water contents were measured by weightloss on drying at 60°C. Using an average grain density of 2.6 gcm"3 (Shipboard Scientific Party, 1989a, b), dry bulk densityvalues were calculated for use in flux calculations. In addition,sea salt concentrations were estimated assuming a pore water sa-linity equivalent to normal seawater. All chemical data presentedhere are corrected for sea salt dilution (and contribution in thecase of Mg and Ca).

The bulk sediment samples were ground in a tungsten car-bide Tema mill and prepared for X-ray fluorescence spectrome-

409

G. B. SHIMMIELD, S. R. MOWBRAY

19 N

Figure 1. Location of Sites 722 and 724 in the northwest Arabian Sea.

try (XRF). This involved the fusion of the sediment powder intoa glass disc using lithium tetraborate and La as a heavy absorber(Norrish and Hutton, 1969) for major elements, and pressingthe powder into a briquette with boric acid backing for minorelements (Shimmield, 1985). The XRF analysis was performedon a Phillips PW1250 sequential automatic X-ray spectrometer.International rock standards were used for calibration. The pre-cision and accuracy of the method are given in Table 1. For Uand Th data, α-spectrometry was performed on total dissolu-tion of the sample using isotope dilution. The extremely precisemethodology is reflected in the presentation of data to two sig-nificant figures (for further details see Shimmield and Mowbray,this volume).

RESULTS AND DISCUSSION

The bulk chemical data obtained from the late Pleistocenesediments in Holes 722B and 724C are given in Appendixes A-C.Major element data are presented for both holes. At Site 722 wealso present minor element data, providing a detailed geochemi-cal record over the last 365 k.y. Appendix D presents minimum,average, and maximum major element values and trace elementvalues for Holes 722B and minimum, average, and maximummajor element value for Hole 724C. Late Pleistocene/Holocenestratigraphy is provided by the δ 1 8θ record of planktonic fora-minifers, courtesy of Prell et al. (this volume) and Pedersen andZahn (this volume) for Holes 722B and 724C, respectively (Fig.2). Age assignments are based on the correlation of the δ 1 8θcurve with the SPECMAP stack (Imbrie et al., 1984). The agemodels from these authors were also used to generate linear sed-imentation rates from which we calculate mass accumulationrates based on our dry bulk density values.

In the Arabian Sea, the bulk sediment composition is con-trolled by both lithogenic and biogenic input, with virtually nohydrothermal component (Shankar et al., 1987; Shimmield, etal., 1990). Consequently, these data are presented as element-to-aluminum ratios in order to examine fluctuations in the chemis-try of the aluminosilicate component that are not due to varia-tions in the biogenic component.

In order to examine the first-order relationships and controlson the geochemical composition of the Pleistocene sediments,statistical analysis of the complete dataset on both holes hasbeen performed. Table 2 presents the results of inter-elementcorrelation, while Table 3 indicates the results of principal com-

Table 1. XRF and α-spectrometry analytical precision and accu-racy for major and minor elements.

Element

SiAlFeCaKTiMnPBaCeCrCuNdNiRbSrVYZnZr

Mean( n = 8)

26.247.995.291.142.390.452.150.10

273673

107112

3412080

40011430

193126

lσ

0.120.030.030.010.010.0040.020.002

36.831.201.830.830.900.710.433.772.110.430.991.12

Estimated total precision8

(as rel. std. dev., lσ)

0.50.40.61.00.41.00.72.01.31.61.70.72.60.60.50.91.81.40.50.9

α-Spectrometry Analytical Precision and Accuracy

Element

UTh

Meanc

(n = 6)

2.739.22

lσ «>

0.170.33

'o r.s.d.

6.23.6

Accuracy

0.050.05

Accuracy

0.0970.0750.0320.0480.0190.0090.0040.013

42.513.514.44.73.64.73.8

10.710.83.86.17.2

Major element mean concentrations and accuracy in wt.%, minor ele-ments in ppm.

a Total precision includes counting error, disc reproducibility, error in re-gression line, and error in matrix mass absorption determinations.

b Accuracy determined from r.m.s.d. of international standards about theregression line.

c Mean concentration and accuracy expressed in ppm.

δ 1 8 θ

40 J 16-1

Hole 724C

C. ruber

Hole 722B

C. αccuti/βr

Figure 2. Oxygen isotope stratigraphy for Hole 724C (Zahn and Peder-sen, this volume) and Hole 722B (Clemens and Prell, this volume). Iso-tope stages assigned by matching to the SPECMAP stack (Imbrie et al.,1984). In this, and following figures, odd numbered interglacial stagesare shaded.

ponent analysis (a data reduction technique for identifying asmall set of variables that account for a large proportion of thetotal variance in the original variables). In Table 3 it is apparentthat the first three eigenvalues (i.e., the variance of the principalcomponents) account for 94.6% of the total variance in majorelement composition for Hole 724B, and 80.4% of the total

410

Table 2. Correlation matrix, Holes 722B and 724C.

Hole 722B

Si Al Fe Ti Mn P Ca Ni Cr V Cu Zn Sr Rb Zr Ba Ce Nd Y U

Al 0.979Fe 0.964 0.979Ti -0.969 -0.955 -0.954Mn 0.982 0.993 0.976 -0.958P 0.839 0.852 0.834 -0.792 0.849Ca 0.540 0.538 0.567 -0.515 0.560 0.450Ni 0.836 0.830 0.856 -0.812 0.834 0.668 0.514Cr 0.910 0.904 0.911 -0.880 0.917 0.721 0.557 0.863V 0.828 0.843 0.836 -0.777 0.823 0.691 0.408 0.827 0.857Cu -0.081 -0.056 -0.051 0.169 -0.071 -0.170 0.031 0.197 0.121 0.241Zn 0.623 0.617 0.609 -0.573 0.604 0.457 0.337 0.737 0.680 0.735 0.446Sr -0.787 -0.768 -0.771 0.821 -0.786 -0.700 -0.425 -0.527 -0.640 -0.495 0.267 -0.348Rb 0.918 0.940 0.927 -0.879 0.924 0.754 0.505 0.850 0.939 0.919 0.126 0.707 -0.602Zr 0.788 0.797 0.786 -0.731 0.803 0.627 0.480 0.740 0.881 0.805 0.126 0.585 -0.379 0.882Ba -0.499 -0.545 -0.520 0.521 -0.556 -0.533 -0.343 -0.234 -0.432 -0.256 0.426 0.052 0.429 -0.466 -0.496Ce 0.568 0.573 0.583 -0.562 0.560 0.415 0.316 0.574 0.607 0.592 0.079 0.393 -0.372 0.628 0.539 -0.238Nd 0.241 0.234 0.232 -0.203 0.222 0.074 0.143 0.347 0.305 0.335 0.269 0.337 -0.018 0.347 0.297 0.047 0.509Y 0.529 0.560 0.561 -0.457 0.539 0.297 0.317 0.681 0.662 0.774 0.522 0.718 -0.143 0.712 0.672 0.026 0.472 0.469U 0.015 0.010 0.020 -0.029 0.018 -0.036 -0.004 0.083 0.066 0.089 0.240 0.083 -0.005 0.030 0.072 0.218 0.071 -0.002 0.191Th 0.645 0.647 0.692 -0.646 0.651 0.592 0.392 0.676 0.667 0.636 0.025 0.396 -0.361 0.648 0.621 -0.409 0.471 0.177 0.354 -0.059

Hole 724C

Si Al Fe Mg Ca K Ti Mn

Al 0.908Fe 0.782 0.960Mg 0.785 0.882 0.888Ca -0.871 -0.899 -0.853 -0.825K 0.901 0.984 0.954 0.926 -0.904Ti 0.933 0.971 0.923 0.882 -0.906 0.969Mn 0.832 0.866 0.837 0.858 -0.790 0.879 0.878P -0.382 -0.451 -0.476 -0.520 0.374 -0.491 -0.465 -0.521


Table 3. Eigenanalysis of correlation matrix of Holes 722B and 724C.

EigenvalueProportionCumulative

Variable

SiAlFeTiMnPCaNiCrVCuZnSrRbZrBaCeNdYUTh

EigenvalueProportionCumulative

Variable

SiAlFeMgCaNaKTiMnP

12.3540.5880.588

PCI

0.2730.2740.275

-0.2660.2720.2160.1530.2590.2750.2590.0310.172

-0.1210.2760.270

-0.1500.2070.1150.189

-0.0060.203

7.6580.7660.766

PCI

-0.334-0.354-0.341-0.336

0.333-0.162-0.357-0.354-0.329

0.189

3.6400.1730.762

PC2

0.1110.1050.087

-0.1380.1270.2090.106

-0.154-0.052-0.138-0.437-0.274-0.419-0.081-0.119-0.342-0.108-0.304-0.351-0.158

0.051

1.0680.1070.873

PC2

-0.169- 0.025

0.0860.0830.089

-0.7330.017

-0.0260.125

-0.628

Hole 722B

1.0990.0520.814

PC3

0.0460.0510.037

-0.0570.0540.149

-0.1460.007

-0.0350.0680.1780.090

-0.260-0.046-0.076

0.214-0.131-0.398-0.013

0.7750.032

Hole 724C

0.5660.0570.929

PC3

-0.0020.1220.179

-0.003-0.175-0.618

0.0920.0870.0370.723

0.8350.0400.854

PC4

0.002-0.005

0.002-0.034

0.009-0.140

0.054-0.130

0.055-0.035-0.231- 0.474-0.031

0.0000.032

-0.0940.4480.4390.0210.477

-0.212

0.2350.0230.953

PC4

-0.6340.0470.4560.4950.2020.1770.107

-0.138-0.180

0.092

0.7660.0360.890

PC5

-0.057-0.084

0.0210.076

-0.032-0.071

0.8920.1130.019

-0.2000.1600.0200.081

-0.0840.008

-0.108-0.195-0.004-0.030

0.1900.055

0.2010.0200.973

PC5

0.027-0.151-0.185

0.2670.4520.034

-0.085-0.082

0.7840.191

0.5330.0250.916

PC6

-0.139-0.141-0.019

0.110-0.139

0.068-0.012

0.092-0.022

0.0760.004

-0.2000.040

-0.073-0.091

0.1320.2900.004

-0.1660.0110.851

0.1340.0130.986

PC6

0.1020.3550.362

-0.4950.6610.0250.1090.194

-0.030-0.005

variance for major, minor, and trace element data in Hole 722B.In Figures 3 and 4 the principal component scores of the com-positional data are plotted on the first two, and on the first andthird, principal components (cf., Li, 1982). According to Fig-ures 3 and 4, the geochemical data broadly define four majorphase associations; (1) aluminosilicate detritus (Al, K, Fe, Rb,Th, Ti, Cr, Zr, V), (2) biogenic carbonate (Ca, Sr), (3) organicmatter (Ba, Cu, U), and (4) phosphatic material (P, Y, Ce, Nd).The remaining elements (Si, Mn, Cu, Ni, Zn) show relation-ships with both biogenic and lithogenic sources. We will nowdescribe the distribution of the elements in detail, and accountfor their association.

Aluminosilicate Detritus FactorThe characteristic element defining this phase group is Al

which is principally derived from aluminosilicate clay minerals.These clay minerals may be of terrestrial origin, or from altera-tion of oceanic basalts and/or hydrothermal exhalations (Mc-Murtry and Yeh, 1981; Bonatti et al., 1983; Shankar et al.,1987; Nath et al., 1989). From studies on the distribution ofsediment type on the Oman continental margin (Shimmield etal., 1989; Sirocko and Sarnthein, 1989) we consider that Al maybe used as an exclusive indicator of clay detritus of continentalterrigenous origin.

Preliminary results (Shipboard Scientific Party, 1989a, b)and Debrebant (this volume) indicate that illite and chlorite(and kaolinite?) with minor amounts of palygorskite form thedominant clay mineralogy. Kolla et al. (1981) have shown thatpalygorskite and illite are rather ubiquitous in the northwestArabian Sea being deposited via eolian transport, the formeroriginating in soils of the Arabian Peninsula and Somalia. Fromthe preliminary principal component analysis we note the closeassociation of Fe, K, Rb, Th, Zr, V, Ti, and Cr with Al. Thiscomposition of the aluminosilicate detritus, but also suggesthow this composition may have varied with time (see discussionbelow). The Fe, K, Rb, and Th content of the terrigenous com-ponent is rather constant over the depth sampled (Figs. 5 and 6)being strongly controlled by the illite/chlorite mineralogy (Boyle,1983; Shankar et al., 1987). This agrees well with the rather uni-form K and Th results and interpretation obtained by the down-hole logging of Unit I (Shipboard Scientific Party, 1989a, b).The Zr/Al profile indicates strong spikes corresponding to simi-lar excursions in the Ti/Al and Cr/Al profiles. We interpretthese as concentrations of heavy minerals (see below). V/Al dis-plays a depth profile in Hole 722B that suggests elevated V con-tent within interglacial stages (particularly 1,5, and 7). While,there is a first-order association with aluminosilicate detritus, Vmay well be concentrated in the sediment during periods of highorganic matter flux via redox processes (Bonatti et al., 1971;

412

INORGANIC GEOCHEMICAL RECORD: PRODUCTIVITY VARIATION, SITES 722 AND 724

/Sr~s

i •0.3 \ • C a , ; -θ'.2

|Ba

-0.8-

0.6-

0.4-

-0.2-

o!i

0 . 2 _

0.4 _

• u

• C u 0 . 6 .

0.8

II

// B N d

L J ^ _ | '

^CeN° 2

• p e N \

J

Fe 'Mn BbI Zr^Si

JCr^'0.

• Ni

1.0

j B a

/ Sr

0.6 -

-0.4-

• U -0.2-1

•Cu

Ola, • C a , -0.2 -o:i

0.6 _

|Zn.Mn

Oil 0.2

ICe '

•Nd

Figure 3. Plots of the principal component factors 1 vs. 2 and factors 1vs. 3 for Hole 722B.

Thomson et al., 1987). We address this point further below.However, the detailed variation in Ti/Al and Cr/Al bears closeexamination. It is clear from Figure 5 that both elements in thealuminosilicate detritus covary to a high degree (Cr:Ti correla-tion of 0.931) and that a high frequency oscillation is present.This downcore variation is not related to glacial/interglacial cy-cles in a simple way (glacial stages are shaded in Fig. 5). By theuse of fast Fourier transform (FFT) spectral analysis (see Weedonand Shimmield, this volume, for details) we have resolved themajor oscillation component into a 25 k.y. cycle for both Ti/Aland Cr/Al in Hole 722B (using the age model of Prell et al., thisvolume) shown in Figure 7. Ti/Al also responds to minor 100k.y. and 41 k.y. forcing. However, the dominant periodicity atthe precession band suggests that an important influence on Ti/Al and Cr/Al variation is the Southwest Monsoon by analogywith other proxy-indicators that have been shown to displaysimilar forcing (Prell and Kutzbach, 1987).

To evaluate more fully the signal contained in the Ti and Crratios, we must assess their geochemical pathway. Ti is knownto be preferentially concentrated in coarser sediment fractions(Spears and Kanaris-Sotiriou, 1976; Schmitz, 1987) due to itsincorporation into heavy minerals such as ilmenite, rutile, tita-

0.6

•si

K*A1 -0.2I •Fe I

-0.2-

jMgMn

0 . 2 -

0.6 -

1.0

1.0

-0.6 _

0.2 0.4 0.6 0.8

Ca

-0.8 -0.6 -0.4 •Mn -0.2

• Al

" K

iMgFe

0.2 _

0.6 -

0.4 0.6

I

o.s

• P) (•Ca)

Figure 4. Plots of the principal component factors 1 vs. 2 and factors 1vs. 3 for Hole 724C.

nomagnetite, and augite. Cr is an important minor element con-stituent of the ultrabasic rocks making up the serpentinites ofthe Oman ophiolite on the Arabian Peninsula and nearby Ma-sirah Island (Moseley and Abbotts, 1979). It is proposed thatthe variation in ratio observed downcore may result from changesin wind intensity (and possible small changes in direction) af-fecting the aerodynamics of the heavy mineral transport. Thissituation is most likely at Site 722 on the crest of the OwenRidge where downslope sediment transport and variations influvial runoff are much less likely. Boyle (1983) pioneered theuse of Ti/Al as an indicator of climate change from his work onsediment accumulation under the Peru Current. He proposedthat Ti/Al fluctuations could be attributed to changes in the in-tensity of eolian transport associated with glacial/interglacialcycles. From our results presented here, and the studies of theseearlier workers, we interpret the oscillation in Ti/Al (and Cr/Al) as a direct indicator of monsoon strength over the late Pleis-tocene, and that the dominant 25 k.y. precession cycle plays animportant role.

413


Fe/AI Rb/AI Th/AI Zr/AI Ti/AI Cr/AI0.0 0.3 1.0 β 12 II 0 β 20 30 40600 700 80020 40 60 10 20 30 40

1 6 J

Figure 5. Element-to-Al weight ratios comprising the aluminosilicate detritus factor with depth in Hole 722B.All ratios except Fe/AI are × 10 ~4.

80 J

Fe/AI K/AI Ti/AI

0.0 0.5 1.0 0.25 0.30 0.35 0.07 0.08 0.09 0.100 Lum•L>-• i •ylÜ•üiu±*á \f i U . I •L ' • ' ' • • V I • Λ • I V I I V ,vl 2^j' r\'\t [ n

- 2 0

- 4 0

r β o

- 8 0

Figure 6. Element-to-Al weight ratios comprising the aluminosilicate detritus factor with depthin Hole 724C.

The Biogenic Component

The calcareous biogenic component at Sites 722 and 724 canbe identified by both the total Ca and Sr XRF analysis. We havecalculated the CaCO3 content of the sediment samples by sub-tracting an aluminosilicate Ca component (in proportion to theamount of Al present) and converting the excess Ca to CaCO3.Thus,

CaCO3 = - (Ca/Alclay ×Altot))

where Ca/Alclay is taken as 0.345 (Turekian and Wedepohl, 1961).This method is in error at very low CaCO3 contents due to un-

certainties in the aluminosilicate ratio, but is unrivalled in preci-sion at the 50%-80% CaCO3 level found at these two sites.However, the method cannot distinguish between CaCO3 of in-situ marine biogenic origin and detrital CaCO3 from the Ara-bian Peninsula.

Examination of the downcore record of CaCO3 in Holes 722Band 724C (Fig. 8) reveals that the highest mean CaCO3 contentis found at the ridge site, and that interglacial periods generallyhave higher concentration levels. It is tempting to conclude thatcarbonate productivity variations are responsible and that inter-glacial periods were therefore more productive, but consider-ation of sediment mass accumulation rate (MAR) is importanthere. Figure 8 displays the MAR for both holes together with

414


0. 40

0.36

0.32

0.28CC

W 0.24

"I

O 0 . 2 0

Q_

0 . 1 6

0 . 1 2

0 . 0 8

. . 8 0 . O X CONr. BASD

15 20 25 30

7 2 . 3 2 4 - 1 1 4 . 5 1 0 . 3 8 . 0 6 . 6 5 . 6 4.

3 6 1 . 5 3 6 . 1 18.1 1 2 . 0 9 . 0 7 . 2 6 . 0 5-2

65 70 75 HARMONIC

k.y.

B

O I 0

Q_

0.8

0.6

0 . 4

0 . 2

0 . 0

i> .

.. 80.OX CONF. BAND

10 15 20 25 30 35 40 45 50 55 60 65 70 75 H A R M O N I C

k.y.

Figure 7. Periodograms for Hole 722B. A. Ti/Al. B. Cr/Al.

7 2 . 3 2 4 . 1 1 4 . 5 1 0 . 3 8 . 0 6-6 5 . 6 4.1

3 6 1 . 5 3 6 . 1 18.1 1 2 . 0 9 . 0 7 . 2 6 . 0 5 . 2

the CaCO3 and terrigenous (1 - CaCO3) content, indicatingthat the terrigenous component dominates the overall MAR andtherefore dilutes the CaCO3 signal antithetically. Higher MAR'soccur during glacial possibly as a result of changes in sea leveland/or aridity and runoff. In order to identify changes in oceanproductivity, through mechanisms such as upwelling, we requirea geochemical indicator which would preserve this signal despitedilution by terrigenous material and variation in CaCO3 disso-lution on the seafloor, and preferably with a large dynamic range(see below).

Sr is very closely correlated with Ca (SπCa = 0.947, Table 1)in Hole 722B. This is unsurprising as seawater Sr is known to beincorporated into the tests of marine organisms during growth

(Table 3). However, the Sr/Ca ratio on the Owen Ridge (Fig. 9)is somewhat higher that has previously been reported and dis-plays an interesting history. Figure 9 displays the close, butdamped or modulated, trend of Sr/Ca in comparison with theδ1 8θ curve. Elevated Sr contents reflect a more negative (heavier)δ1 8θ signal in the planktonic foraminifer {Globigerinoides saccu-lifef) corresponding to interglacial stages. Perhaps the Sr con-tent of the biogenic CaCO3 is reflecting a temperature or speciesor vital effect control. We do not believe diagenetic overprinting(Baker et al., 1982) is responsible due to the shallow depth ofthis core. In addition, marine barite is known to contain Sr(0.2-3.4 mol


- 2MAR. (g cm"-ky)

16-3

CαCO3 (Wt.*)

-12

-16M.A.R. (g cm~2-ky)

Uéü••if 0

20-

50 100 0 50 100 0 10J L . L • L L , L U • L • • U • • L i ^ L H • L • • u A , L I L.L.L, L• L• U k • x . l * i L L , Ü U ^ ^ • ' 'I•I U.< »••••'.AJU

Figure 8. CaCO3 (wt%), terrigenous component (100 - CaCO3; wt


Si/AI Si/AI

7 2.5 3.0 3.5 4.0 4.5 5.0 5.5O-J.liLJ.ü.U.ü•JJJ•LJüü•J-U•tJüüüüié^i 041

80 J 16-1

Figure 10. Si/AI (weight ratio) with depth in Holes 722B (left) and 724C (right).

unpublished opal data (determined by wet chemistry) from thesite survey core (RC27-61; D. Murray, pers. comm., 1989) sug-gests that the spikes are indeed due to higher contents of bio-genic opal. If this record reflects a constant clay and quartz in-put, with additions of biogenic opal, then the periodicity of therecord (see Weedon and Shimmield, this volume) at 56 k.y. and25/19 k.y. reflects both precession and an unknown forcing com-ponent. The 56 k.y. periodicity has also been observed in SiO2records from this leg (S. Clemens, pers. comm., 1989) but re-mains unexplained. At Site 724 the much higher Si/AI ratio,and the core location on the continental slope, suggests thatquartz may be rather more dominant. This is confirmed by smearslide analysis (Shipboard Scientific Party, 1989a, b) which indi-cates about 10% quartz in Unit I of Hole 724C, and only traceamounts in Hole 722B. Interestingly, the Si/AI profile in Site724 is antithetically correlated with volume magnetic suscepti-bility (Shipboard Scientific Party, 1989a, b) suggesting that quartzdilutes the susceptibility record.

Organic Matter (Productivity) Factor

As we have seen above, both CaCO3 and Si are unreliable in-dicators of the paleoceanographic record of productivity varia-tion in the Arabian Sea. However, one element, Ba, is concen-trated by marine organisms and may resist remineralization("dissolution residue," Dymond, 1981) providing a tracer of pa-leoproductivity. Since the work of Revelle et al. (1955) many au-thors have commented on the association of Ba, opal, and bio-genic sedimentation. Despite the association of Ba-enriched sedi-ments and regions of upwelling or enhanced productivity, nocausal relationship has been definitely established (see review inSchmitz, 1987). Recent studies have suggested that Ba may be inheavy mineral granules functioning as statoliths (Fenchel andFinlay, 1984) within protozoans such as Xenophyophoria andLoxodes (Finlay et al., 1983). Very recently, Ba has been the sub-ject of study in marine particles from the Gulf Stream (Bishop,1988) and within the calcareous tests of benthic foraminifers(Lea and Boyle, 1989) and corals (Lea et al., 1989). Within theIndian Ocean the recent study of Schmitz (1987) has illustratedthe use of Ba as a tracer of plate movement beneath the equato-rial upwelling zone on a time scale of millions of years. To ourknowledge there is no high-resolution record of Ba from an up-welling area influenced by climate change over a time scale ofthousands of years.

Figure 11 illustrates the variation with depth of Ba/Al at Site722B on the Owen Ridge. The record is striking for two reasons:(1) the Ba/Al has the largest dynamic range of any chemicalvariable measured here, and (2) the profile bears an almost per-fect correlation with the δ 1 8θ stratigraphy. Clearly, elevated Bacontents are found during interglacial stages and must thereforereflect periods of enhanced productivity. (This conclusion holdseven when considered in terms of flux, given the higher MAR ofglacial periods. This is the advantage of having a tracer with solarge a dynamic range.) In Figure 12 a periodogram of Ba/Aldisplays the strong 100 k.y. cycle that is apparent in the depthprofile. As well as eccentricity cycle, both tilt (42 k.y.) and pre-cession (23/16 k.y.) are in evidence, again confirming the simi-larity of the Ba profile to the δ 1 8θ record. The phasing of thisrecord is discussed further in Weedon and Shimmield (this vol-ume).

From wind strength indicators (e.g., Ti/Al) we believe thatthe monsoon responds to forcing in the precession band. As up-welling is linked through Ekman transport to wind stress, it isexpected that Ba, as a productivity indicator, should also dis-play similar precessional forcing. The fact that longer cycle("global") forcing is also very evident suggests that nutrientsupply to the northwest Arabian Sea may be important. In thiscontext, recent models on deep and intermediate water ventila-tion or stagnation are pertinent (Keir, 1988; Duplessy et al.,1988) as shown by Cd/Ca tracers in benthic foraminifers (Boyle,1986). Recent work by Boyle (1988) and Boyle and Keigwin(1987) has shown that intermediate waters in the North Atlanticbecame nutrient depleted together with reduced North AtlanticDeep Water Flux during the last glacial episode. As the predom-inant source of nutrients in this area is through upwelling of in-termediate waters, changes in the nutrient profile of open oceanwaters during glacial time may account for the weaker glacialproductivity identified from the Ba/Al signal. Further paleocean-ographic studies should concentrate on establishing the nutrientlevels of Indian ocean intermediate waters.

In addition to Ba as a direct indicator of changing productiv-ity, the associated organic matter detritus will also affect thesediment geochemistry, either through direct metal complexingor through redox chemistry. Recently, studies by Thomson et al.(1987) have shown the importance of progressive redox fronts inpreserving minor metal profiles in non-steady state conditions.Finney et al. (1988) have argued for productivity-induced redox

417


Bα/AI Cu/Al Ni/AI Zn/Al U/Th 61βO (°/oo)1000 0 10 20 30 15 25 35 10 20 30 1 2 3 *1 0 -1 -3

Figure 11. Element-to-Al weight ratios comprising the productivity factor with depth in Hole722B, together with the δ 1 8 θ stratigraphy. All ratios are × 10"4 except U/Th.

1 3 4 9 . 0 -

1 2 1 4 . I -

1 0 7 9 . 2 -

^ 8 0 9 . 4 -

3

O 674.5 -

0_

539.6 -

404.7 -

269.8 -

1 3 4 . 9 -

0 - 0

72.3 24.1 14.5 10 3 8.0 6.6 5-6 4.8

• • . 8 0 . O X CONF• BAND

361.5 36.1 IB.I 12.0 9.0 7.2 6.0 5.2

Figure 12. Ba/Al periodogram for Hole 722B.

variations in controlling transition metal distributions in sedi-ments from the eastern equatorial Pacific. In Figure 11, U andCu are both enriched relative to aluminosilicate levels at depthscorresponding to higher productivity periods (defined by Ba/Al). As these two metals (and V) are often associated with morereducing conditions brought about by higher organic matterfluxes (or expansion of the OMZ to intersect the ridge crest) thisobservation is consistent. The weaker association of Ni/AI andZn/Al is possibly incurred as particulate organic matter is knownto be an effective scavenger of transition metals. The impor-tance of subsurface redox fronts and accumulation rate fluxes isdiscussed further in Shimmield and Mowbray (this volume).Sediment trap studies in the Sargasso Sea (Jickells et al., 1984)have demonstrated the very close association of Cu, Ni, V, andZn (also Fe, Mn, P, and Pb) fluxes with total organic carbonflux. They attribute the close association to seasonality drivenby changes in primary productivity in the overlying surface wa-ters. Particulate forms of the elements are rapidly consolidatedand sedimented with the organic matter.

Phosphatic Factor

The occurrence of phosphatic material accumulating in sedi-ments underlying upwelling zones has been long recognized(Burnett, 1977; and others). This material may be diagenetic inorigin, or of biogenic skeletal (fish teeth and bones) nature.Both phases are known to concentrate the rare earth elements.In Figure 3 the clear association of P with Ce, Y, and Nd maybe seen. Similar statistical analysis by Li (1982) also recognizedthe existence of phosphate minerals and REE's in sediments. AtSite 722 the phosphatic sediments (identified by the P/Al ratio)are more common during interglacial stages (Fig. 13) with anaverage P/Al ratio of 0.025 in the upper 16 m. We may attributethis distribution to the effect of elevated interglacial productiv-ity, as identified by the tracers described above. However, at Site724 a rather different distribution is recorded (Fig. 13). Here thebaseline P/Al ratio is roughly the same (0.02-0.03) but highlyenriched phosphate horizons (reaching a maximum P/Al of— 0.4) are recorded. These enriched horizons also occur within

418


P/AI P/AI(cθ (b)

o.o p.i P. £...... P. f* P. ,4 ° 00 ° 01 ° 02 ° 03 ° c?4 ° 05

80 ->

Figure 13. P/AI weight ratio with depth for Holes 722B (left) and 724C (right).

interglacial sediments suggesting their origin is also linked tohigh productivity episodes. The phase containing the phosphateis unknown, but phosphate nodules at a depth of about 44 mwere recorded by the Shipboard Scientific Party (1989b) in Hole724A.

CONCLUSION

The results presented here together with their interpretationsuggest that the Oman margin has experienced major changesin productivity and upwelling history during the late Pleisto-cene. Through the use of high-resolution inorganic geochemis-try, together with a unique sedimentary record provided by hy-draulic piston coring, we have been able to define the pattern ofthese climate changes.

The Southwest Monsoon (and associated northwest winds—the Shamal; Sirocko and Sarnthein, 1989) appears to be respon-sible for the bulk of the eolian dust input to the northwest Ara-bian Sea. This dust input may be clearly identified by the Ti/Aland Cr/Al record, and occurs with a frequency that suggestsforcing by orbital precession. This result is in agreement withother proxy-indicators that have been shown to display similarforcing (Prell and Kutzbach, 1987).

The record of biogenic productivity is more involved, re-sponding to both local upwelling intensity and changes in theglobal ocean/climate system. The record of bulk biogenic car-bonate is strongly influenced by, and inversely correlated with,terrigenous aluminosilicate detritus. Some biogenic silica occursat Site 722. Using time series analysis, the opal distributioncurves reflect both precession and an unknown forcing compo-nent at 56 k.y. The dominant contribution to the total Si mea-sured in these sediments is from clay and quartz. The questionof why an upwelling area that at the present day supports highopal productivity (diatoms), but fails to record changes in thisopal productivity within the sediments, requires further study.

In this study Ba has proved to be an excellent indicator ofchanges in productivity with time. The record closely followsthe δ1 8θ signal recorded in planktonic foraminifers, suggestingthat not only local upwelling, but ocean-wide changes in nutri-ent supply, may influence the biological community. Respond-ing to these changes in productivity is the flux of biological de-tritus (fecal material, tissue, skeletons) to the sediments, whichdrive redox variations in the sediment, and/or changes in the in-tensity and depth of the oxygen minimum zone. This is recordedin the geochemistry of Cu, Ni, Zn, V, and U, all of which iden-tify interglacial episodes as being more productive.

The detritus of biogenic material promotes active phospho-genesis within the sediments. Both diagenetic enrichment ofphosphate and the accumulation of phosphatic skeletal hardparts occurs within the sediments of the Oman Margin andOwen Ridge. Their distribution also reflects the higher produc-tivity of interglacial episodes. This observation that temporaltrends in productivity in the northwest Arabian Sea are out ofphase with those in the Panama Basin and off northwest Africa,where higher productivity occurs during glacial episodes, willrequire an answer from integrated studies of ocean productivityand upwelling through time.

ACKNOWLEDGMENTS

We wish to thank staff and crew of the Ocean Drilling Pro-gram and the JOIDES Resolution for the opportunity to under-take this study. We especially grateful to Warren Prell, Kay Emeis,Brian Price, Tom Pedersen, Dave Murray, and Steve Clemensfor helpful discussions on this project. Drs. R. Francois and H.-J. Brumsack provided critical and stimulating reviews. GBS ac-knowledges the support of NERC Grant GST/02/315 from theODP Special Topic fund.

REFERENCES

Adelseck, C. G., Jr., and Anderson, T. E, 1978. The late Pleistocenerecord of productivity fluctuations in the eastern equatorial PacificOcean. Geology, 6:388-391.

Baker, P. A., Gieskes, J. M., and Elderfield, H., 1982. Diagenesis ofcarbonates in deep-sea sediments: evidence from Sr 2 +/Ca 2 + ratiosand interstitial dissolved Sr2"1" data. J. Sediment. Petrol, 52:71-82.

Bishop, J.K.B., 1988. The barite-opal organic carbon association inoceanic particulate matter. Nature, 332:341-343.

Bonatti, E., Fisher, D. E., Joensuu, O., and Rydell, H. S., 1971. Post-depositional mobility of some transition elements, phosphorus, ura-nium and thorium in deep-sea sediments. Geochim. Cosmochim.Acta, 35:189-201.

Bonatti, E., Simmons, E. C , Berger, D., Hamlyn, P. R., and Law-rence, L., 1983. Ultramafic rock/seawater interaction in the oceaniccrust. Mg-silicate (sepiolite) deposit from the Indian Ocean floor.Earth Planet. Sci. Lett., 62:229-238.

Boyle, E. A., 1983. Chemical accumulation variations under the PeruCurrent during the past 130,000 years. J. Geophys. Res., 88:7667-7680.

, 1986. Paired carbon isotope and cadmium data from benthicforaminifera: implications for changes in oceanic phosphorus, oce-anic circulation, and atmospheric carbon dioxide. Geochim. Cos-mochim. Acta, 50:265-276.

419


, 1988. The role of vertical chemical fractionation in control-ling late Quaternary atmospheric carbon dioxide. J. Geophys. Res.,93:15701-15714.

Boyle, E. A., and Keigwin, L., 1987. North Atlantic thermohaline cir-culation during the past 20,000 years linked to high-latitude surfacetemperature. Nature, 330:35-40.

Church, T. M., 1979. Marine barite. In Burns, R. G. (Ed.), Reviews inMineralogy (Vol. 6). Mineral Soc. Am., 175-209.

CLIMAP Project Members, 1976. The surface of the ice-age Earth. Sci-ence, 191:1131-1137.

Duplessy J. C , Shackleton, N. J., Fairbanks, R. G., Labeyrie, L.,Oppo, D., and Kallel, N., 1988. Deepwater source variations duringthe last climatic cycle and their impact on global deepwater circula-tion. Paleoceanography, 3:343-360.

Dymond, J., 1981. Geochemistry of Nazca plate surface sediments: Anevaluation of hydrothermal, biogenic, detrital, and hydrogenoussources. Mem. Geol. Soc. Am., 154:133-173.

Fenchel, T., and Finlay, B. J., 1984. Geotaxis in the ciliated protozoan,Loxodes. J. Exp. Biol., 110:17-33.

Finlay, B. J., Hetherington, N. B., and Davison, W., 1983. Active bio-logical participation in lacustrine barium geochemistry. Geochim.Cosmochim. Ada, 47:1325-1329.

Finney, B. P., Lyle, M. W., and Heath, G. R., 1988. Sedimentation atMANOP Site H (eastern equatorial Pacific) over the past 400,000years: climatically induced redox variations and their effects on tran-sition metal cycling. Paleoceanography, 3:169-189.

Imbrie, J., Hays, J. D., Martinson, D. G., Mclntyre, A., Mix, A. C ,Morley, J. J., Pisias, N. G., Prell, W. L., and Shackleton, N. J.,1984. The orbital theory of Pleistocene climate: support from a re-vised chronology of the marine delta δ 1 8 θ record. In Berger, A., Im-brie, J., Hays, J., Kukla, G., and Saltzman, B. (Eds.), Milankovitchand Climate (Pt. 1): Dordrecht (D. Reidel), 269-305.

Jickells, T. D., Deuser, W. G., and Knap, A. H., 1984. The sedimenta-tion rates of trace elements in the Sargasso Sea measured by sedi-ment trao. Deep-Sea Res. Part A, 31:1169-1178.

Keir, R. S., 1988. On the late Pleistocene ocean geochemistry and circu-lation. Paleoceanography, 3:413-445.

Kolla, V., Ray, P. K., and Kostecki, J. A., 1981. Surficial sediments ofthe Arabian Sea. Mar. Geol., 41:183-204.

Labracherie, M., Barde, M.-F., Moyes, J., and Pujos-Lamy, A., 1983.Variability of upwelling regimes (northwest Africa, south Arabia)during the latest Pleistocene: a comparison. In Suess, E., and Thiede,J. (Eds.), Coastal Upwelling, Its Sediment Record: New York (Ple-num), 347-364.

Lea, D., and Boyle, E. A., 1989. Barium content of benthic foraminif-era controlled by bottom-water composition. Nature, 338:751-753.

Lea, D. W., Shen, G. T, and Boyle, E. A., 1989. Coralline barium re-cords temporal variability in equatorial Pacific upwelling. Nature,340:373-376.

Li, Y.-H., 1982. Interelement relationship in abyssal Pacific ferroman-ganese nodules and associated pelagic sediments. Geochim. Cosmo-chim. Ada, 46:1053-1060.

Lyle, M., Heath, G. R., Murray, D. W., Finney, B. P., Dymond, J.,Robbins, J. M., and Brooksforce, K., 1988. The record of late Pleis-tocene sedimentation in the eastern equatorial Pacific Ocean. Pale-oceanography, 3:39-59.

McMurtry, G. M., and Yeh, H. W., 1981. Hydrothermal clay mineralformation of East Pacific Rise and Bauer Basin sediments. Chem.Geol., 32:189-205.

Moseley, F., and Abbotts, I. L., 1979. The Ophiolite melange of Ma-sirah, Oman. J. Geol. Soc. London, 136:713-724.

Nath, B. G., Rao, V. P., and Becker, K. P., 1989. Geochemical evidenceof terrigenous influence in deep-sea sediments up to 8°S in the cen-tral Indian basin. Mar. Geol., 87:301-313.

Norrish, K., and Hutton, J. T., 1969. An accurate X-ray spectrographicmethod for the analysis of a wide range of geological samples. Geo-chim. Cosmochim. Ada, 33:431-453.

Pedersen, T. F., 1983. Increased productivity in the eastern equatorialPacific during the last glacial maximum (19,000 to 14,000 yr B.P.).Geology, 11:16-19.

Pedersen, T. F., Pickering, M., Vogel J. S., Southon, J. N., and Nelson,D. E., 1988. The response of benthic foraminifera to productivitycycles in the eastern equatorial Pacific: faunal and geochemical con-straints on glacial bottom water oxygen levels. Paleoceanography, 3:157-168.

Prell, W. L., 1984a. Monsoonal climate of the Arabian Sea during thelate Quaternary: a response to changing solar radiation. In Berger,A. L., Imbrie, J., Hays, J., Kukla, G., and Saltzman, B. (Eds.). Mi-lankovitch and Climate (Pt. 1): Dordrecht (D. Reidel), 349-366.

, 1984B. Variation of monsoonal upwelling: a response tochanging solar radiation. In Hansen, J. E., and Takahashi, T. (Eds.),Climatic Processes and Climate Sensitivity. Am. Geophys. Union,Maurice Ewing Sen, 5:48-57.

Prell, W. L., and Kutzbach, J. E., 1987. Monsoon variability over thepast 150,000 years. J. Geophys. Res., 92:8411-8425.

Prell, W. L., and Van Campo, E., 1986. Coherent response of ArabianSea upwelling and pollen transport to late Quaternary monsoonalwinds. Nature, 323:526-528.

Quasim, S. Z., 1982. Oceanography of the northern Arabian Sea. Deep-Sea Res. Part A, 29:1041-1068.

Rao, D. P., and Jayaramna, R., 1970. On the occurrence of oxygenmaxima and minima in the upper 500 meters of the north-west In-dian Ocean. Proc. Indian Acad. ScL, 71B:230-246.

Revelle, R., Bramlette, M., Arrhenius, G., and Goldberg, E. D., 1955.Pelagic sediments of the Pacific. Spec. Pap.—Geol. Soc. Am., 62:221-235.

Schmitz, B., 1987. The TiO2/Al2O3 ratio in the Cenozoic Bengal Abys-sal Fan sediments and its use as a paleostream energy indicator. Mar.Geol., 76:195-206.

Sen Gupta, R., Fondekar, S. P., Sankaranarayanan, V. E., and De Sousa,S. N., 1975. Chemical oceanography of the Arabian Sea. Part 1.Hydrochemical and hydrographical features of the northern basin.Indian J. Mar. ScL, 4:136-140.

Shankar, R., Subbarao, K. V., and Kolla, V., 1987. Geochemistry ofsurface sediments from the Arabian Sea. Mar. Geol., 76:253-279.

Shimmield, G. B., 1985. The geochemistry and mineralogy of Pacificsediments, Baja California, Mexico [Ph.D. dissert.]. Univ. of Edin-burgh, Edinburgh.

Shimmield, G. B., Price, N. B., and Pedersen, T. F., 1990. The influ-ence of hydrography, bathymetry, and productivity on sediment typeand composition from the Oman margin and the northwest ArabianSea. In Robertson, A.H.F., Searle, M. P., and Ries, A. C. (Eds.),The Geology and Tectonics of the Oman Region. Spec. Publ. Geol.Soc, 49:761-771.

Shipboard Scientific Party, 1989a. Site 722. In Prell, W. L., Niitsuma,N., et al., Proc. ODP, Init. Repts., 117: College Station, TX (OceanDrilling Program), 255-318.

, 1989b. Site 724. In Prell, W. L., Niitsuma, N., et al., Proc.ODP, Init. Repts., 117: College Station, TX (Ocean Drilling Pro-gram), 385-418.

Sirocko, F, and Sarnthein, M., 1989. Wind-borne deposits in the north-west Indian Ocean: record of Holocene sediments versus modernsatellite data. In Leinen, M., and Sarnthein, M. (Eds.), Paleoclima-tology and Paleometeorology: Modern and Past Patterns of GlobalAtmospheric Transport. NATO ASI Sen, 401-433.

Slater, R. D., and Kroopnick, P., 1984. Controls on dissolved oxygendistribution and organic carbon deposition in the Arabian Sea. InHaq, B. U., and Milliman, J. D. (Eds.), Marine Geology and Ocean-ography of Arabian Sea and Coastal Pakistan. New York (Van Nos-trand Reinhold), 305-313.

Spears, D. A., and Kanaris-Sotiriou, R., 1976. Titanium in some Car-boniferous sediments from Great Britain. Geochim. Cosmochim.Ada, 40:345-351.

Thomson, J., Colley, S., Higgs, N., Hydes, D. J., Wilson, T.R.S., andS^rensen, J., 1987. Geochemical oxidation fronts in NE Atlanticdistal turbidites and their effects on the sedimentary record. InWeaver, P.P.E., and Thomson, J. (Eds.), Geology and Geochemistryof Abyssal Plains, Spec. Publ. Geol. Soc, 31:167-178.

Turekian, K. K., and Wedepohl, K. H., 1961. Distribution of the ele-ments in some major units of the earth's crust. Geol. Soc. Am.Bull, 72:175-192.

Van Campo, E., Duplessy, J. C , and Rossignol-Strict, M., 1982. Cli-matic conditions deduced from a 150-kyr oxygen isotope-pollen re-cord from the Arabian Sea. Nature, 296:56-59.

Date of initial receipt: 28 September 1989Date of acceptance: 20 July 1990Ms 117B-170

420


APPENDIX AHole 722B Cores 1H and 2H Corrected for Salt Contribution and Dilution.

Sampleidentification

722B-1H-01, 06-08 cm722B-1H-01, 16-18 cm722B-1H-01, 26-28 cm722B-1H-01, 36-38 cm722B-1H-01, 46-48 cm722B-1H-01, 56-58 cm722B-1H-01, 66-68 cm722B-1H-01, 76-78 cm722B-1H-01, 86-88 cm722B-1H-01, 96-98 cm722B-1H-01, 106-108 cm722B-1H-01, 116-118 cm722B-1H-01, 126-128 cm722B-1H-01, 136-138 cm722B-1H-01, 146-148 cm722B-1H-02, 06-08 cm722B-1H-02, 16-18 cm722B-1H-02, 26-28 cm722B-1H-02, 36-38 cm722B-1H-02, 46-48 cm722B-1H-02, 56-58 cm722B-1H-02, 66-68 cm722B-1H-02, 76-78 cm722B-1H-02, 86-88 cm722B-1H-02, 96-98 cm722B-1H-02, 106-108 cm722B-1H-02, 116-118 cm722B-1H-02, 126-128 cm722B-1H-02, 136-138 cm722B-1H-02, 146-148 cm722B-1H-03, 06-08 cm722B-1H-03, 16-18 cm722B-1H-03, 26-28 cm722B-1H-03, 36-38 cm722B-1H-03, 46-48 cm722B-1H-03, 56-58 cm722B-1H-03, 66-68 cm722B-1H-03, 76-78 cm722B-1H-03, 86-88 cm722B-1H-03, 96-98 cm722B-1H-03, 106-108 cm722B-1H-03, 116-118 cm722B-1H-03, 126-128 cm722B-1H-03, 136-138 cm722B-1H-03, 146-148 cm722B-1H-04, 06-08 cm722B-1H-04, 16-18 cm722B-1H-04, 26-28 cm722B-1H-04, 36-38 cm722B-1H-04, 46-48 cm722B-1H-04, 56-58 cm722B-1H-04, 66-68 cm722B-1H-04, 76-78 cm722B-2H-01, 06-08 cm722B-2H-01, 16-18 cm722B-2H-01, 26-28 cm722B-2H-01, 36-38 cm722B-2H-01, 46-48 cm722B-2H-01, 56-58 cm722B-2H-01, 66-68 cm722B-2H-01, 76-78 cm722B-2H-01, 86-88 cm722B-2H-01, 96-98 cm722B-2H-01, 106-108 cm722B-2H-01, 116-118 cm722B-2H-01, 126-128 cm722B-2H-01, 136-138 cm722B-2H-01, 146-148 cm722B-2H-01, 06-08 cm722B-2H-01, 16-18 cm722B-2H-02, 26-28 cm722B-2H-02, 36-38 cm722B-2H-02, 46-48 cm722B-2H-02, 56-58 cm722B-2H-02, 66-68 cm

Depth(mbsf)

0.070.170.270.370.470.570.670.770.870.971.071.171.271.371.471.571.671.771.871.972.072.172.272.372.472.572.672.772.872.973.073.173.273.373.473.573.673.773.873.974.074.174.274.374.474.574.674.774.874.975.075.175.275.625.675.775.875.976.076.176.276.376.476.576.676.776.876.977.077.177.277.377.477.577.67

Density(g/cm3)

0.770.790.870.910.870.930.970.971.000.960.950.971.020.950.971.040.941.010.941.000.880.840.831.070.940.890.920.960.940.901.001.101.001.101.141.081.030.991.071.050.950.931.071.070.961.040.960.980.86

(

(

1

.07

.05

.11

.01).93.00.04

).89.06.10.25.24.20.14.06.10.14.10.16.05.01.21.06.07.11.08

aAge(k.y.)

6.07.59.0

10.211.512.814.015.016.117.219.221.222.325.527.729.831.934.036.038.140.142.144.146.248.250.352.354.356.358.460.462.565.167.770.173.276.279.284.189.093.598.0

103.2107.5113.1116.8119.8122.8124.1126.0127.5129.2132.0135.8137.1138.2140.5142.6144.1145.2147.6149.4151.2152.7154.2156.2158.0159.5161.4163.2165.0166.8168.7170.7172.8

Si Al(wt%) (wt%) (

6.1764.7484.5557.4186.0098.0778.6739.260

10.2239.3739.1459.0359.6469.0389.197

10.1889.3589.0089.1669.9527.6918.0398.9639.2468.8627.6908.0197.8207.4967.2079.369

12.21711.01010.10910.728 .10.1787.8676.6048.720 :7.838 .7.6806.9747.6677.0356.1098.802 :7.6446.1055.6359.234 :9.281 ;9.206 ;9.444 ;

1.4091.1111.1111.9731.5782.1152.2192.3402.6872.3892.3442.3122.4472.3272.3352.6032.3712.2732.3652.6061.9831.8832.0362.0142.251(.8281.756(.9111.8921.7302.4015.1342.8342.6072.7362.6782.0091.6702.3082.0651.9131.6002.019.890

FewtVo)

3.8903.7233.7321.2401.0061.312(.3221.426(.636(.464(.5071.448(.5541.4371.465(.592(.4891.4071.445(.4741.2011.1911.2651.4011.368(.1801.1371.1831.1781.1161.4601.8961.6741.5741.6721.6061.230.097.514

1.2835.1301.044.231.161

.466 0.9702.347.927.552.411 (

2.4662.456>.382'.452

8.235 2.1238.436 i8.978 :9.584 :9.425 :

2.145S.2652.4421.386

9.355 2.402 ]9.100 2.339

11.982 :12.599 :

1.0591.202

11.323 2.850 ]11.650 2.935n.879 :12.557 I

!.O29.210

11.813 3.052 ]12.613 :11.021 :io.o3i :

1.284 ]'.834 11.578 1

10.247 2.625 19.493 2.487 ]

10.192 2.704 ]10.105 2.658 110.088 2.656 1

.479

.188

.009

.429

.499

.416

.499

.505

.419

.417

.437

.499

.597

.746

.832

.913

.779

.865

.838

.968

.919

.933

.679

.652

.646

.469

.618

.726

.717

Ca(wt%)

30.31132.31832.28328.64830.30627.24626.66125.70524.74125.45426.07426.05325.56126.20226.12324.61125.63426.59026.22924.13228.25127.89426.59525.50626.27128.14328.11527.30926.86128.91826.04623.77024.16725.25823.04024.66728.32829.95927.04826.85027.67929.47228.84129.30430.62226.92228.25930.68331.31026.06225.76526.31925.55126.96626.83426.47726.02225.49125.64325.81022.24621.61823.43022.78922.71321.59822.12821.39723.49025.03224.40825.90524.73124.79324.971

Ti(wt%)

0.0950.0730.0710.1350.1090.1470.1530.1680.1870.1720.1660.1660.1720.1660.1680.1850.1720.1640.1670.1840.1450.1410.1530.1450.1630.1330.1270.1340.1310.1240.1710.2220.2040.1880.2030.1810.1440.1180.1610.1400.1460.1170.1390.1270.1030.1610.1280.0990.0930.1680.1690.1650.1710.1490.1510.1580.1700.1660.1670.1620.2150.2310.2060.2120.2190.2260.2160.2270.2010.1780.1790.1700.1850.1850.187

Mn(wt%)

0.0180.0190.0180.0250.0190.0270.0240.0290.0340.0280.0250.0260.0280.0290.0260.0260.0270.0270.0250.0310.0240.0240.0250.0220.0250.0210.0210.0250.0200.0230.0260.0320.0300.0290.0280.0250.0260.0220.0260.0210.0340.0240.0220.0200.0210.0250.0260.0230.0250.0280.0290.0320.0290.0230.0270.0270.0300.0300.0300.0300.0360.0360.0340.0340.0330.0370.0330.0340.0290.0310.0290.0310.0270.0320.030

P(wt%)

0.0410.0350.0340.0420.0370.0450.0460.0490.0470.0490.0520.0490.0470.0510.0520.0520.0540.0520.0530.0490.0520.0460.0520.0520.0540.0580.0520.0450.0410.0460.0460.0500.0490.0490.0520.0500.0500.0540.0520.0510.0480.0440.0510.0420.0460.0480.0480.0400.0400.0510.0520.0560.0580.0510.0500.0510.0480.0550.0500.0670.0470.0490.0530.0520.0540.0510.0540.0510.0550.0500.0470.0450.0440.0460.047

421


Appendix A (continued).


722B-2H-02, 76-78 cm722B-2H-02, 86-88 cm722B-2H-02, 96-98 cm722B-2H-02, 106-108 cm722B-2H-02, 116-118 cm722B-2H-02, 126-128 cm722B-2H-02, 136-138 cm722B-2H-02, 146-148 cm722B-2H-03, 06-08 cm722B-2H-03, 16-18 cm722B-2H-03, 26-28 cm722B-2H-03, 36-38 cm722B-2H-03, 46-48 cm722B-2H-03, 56-58 cm722B-2H-03, 66-68 cm722B-2H-03, 76-78 cm722B-2H-03, 86-88 cm722B-2H-03, 96-98 cm722B-2H-03, 106-108 cm722B-2H-03, 116-118 cm722B-2H-03, 126-128 cm722B-2H-03, 136-138 cm722B-2H-03, 146-148 cm722B-2H-04, 06-08 cm722B-2H-04, 16-18 cm722B-2H-04, 26-28 cm722B-2H-04, 36-38 cm722B-2H-04, 46-48 cm722B-2H-04, 56-58 cm722B-2H-04, 66-68 cm722B-2H-04, 76-78 cm722B-2H-04, 86-88 cm722B-2H-04, 96-98 cm722B-2H-04, 106-108 cm722B-2H-04, 116-118 cm722B-2H-04, 126-128 cm722B-2H-04, 136-138 cm722B-2H-04, 146-148 cm722B-2H-05, 06-08 cm722B-2H-05, 16-18 cm722B-2H-05, 26-28 cm722B-2H-05, 36-38 cm722B-2H-05, 46-48 cm722B-2H-05, 56-58 cm722B-2H-05, 66-68 cm722B-2H-05, 76-78 cm722B-2H-05, 86-88 cm722B-2H-05, 96-98 cm722B-2H-05, 106-108 cm722B-2H-05, 116-118 cm722B-2H-05, 126-128 cm722B-2H-05, 136-138 cm722B-2H-05, 146-148 cm722B-2H-06, 06-08 cm722B-2H-06, 16-18 cm722B-2H-06, 26-28 cm722B-2H-06, 36-38 cm722B-2H-06, 46-48 cm722B-2H-06, 56-58 cm722B-2H-06, 66-68 cm722B-2H-06, 76-78 cm722B-2H-06, 86-88 cm722B-2H-06, 96-98 cm722B-2H-06, 106-108 cm722B-2H-06, 116-118 cm722B-2H-06, 126-128 cm722B-2H-06, 136-138 cm722B-2H-06, 146-148 cm722B-2H-07, 06-08 cm722B-2H-07, 16-18 cm722B-2H-07, 26-28 cm722B-2H-07, 36-38 cm

Depth(mbsf)

7.777.877.978.078.178.278.378.478.578.678.778.878.979.079.179.279.379.479.579.679.779.879.97

10.0710.1710.2710.3710.4710.5710.6710.7710.8710.9711.0711.1711.2711.3711.4711.5711.6711.7711.8711.9712.0712.1712.2712.3712.4712.5712.6712.7712.8712.9713.0713.1713.2713.3713.4713.5713.6713.7713.8713.9714.0714.1714.2714.3714.4714.5714.6714.7714.87

Density(g/cm3)

1.121.101.131.071.011.061.041.010.980.970.901.010.880.991.071.161.141.051.061.131.081.051.020.980.950.981.040.990.970.990.910.900.931.021.021.161.161.191.391.201.141.141.031.071.071.11.121.091.091.011.051.101.121.061.030.981.011.021.061.101.101.111.120.941.051.101.051.051.071.071.121.11

aAge(k.y.)

175.2177.6180.0182.0184.1186.2187.7189.7191.1193.2197.6200.8204.3208.0211.5215.0218.5222.1225.8229.8233.4237.0239.0241.0242.9244.8246.3248.1249.8251.7253.2255.0256.6258.2259.8261.6263.2265.0266.5268.0271.5277.0281.5286.0289.0292.0295.0298.0302.0306.0310.0314.0318.0322.0326.0330.0331.5333.1334.6336.1337.6338.8340.8342.8344.8347.0349.2351.6353.7356.0360.5365.0

Si Al(wt%) (wt%) (

8.9169.970

10.26310.18010.1536.8436.5515.7996.3786.3347.1655.6175.3467.1997.961

10.70010.1188.080 :7.968 :8.684 ;7.694 -6.4255.2568.1547.1097.9389.253 :8.264 :8.231 :8.0717.8648.5078.5008.887 :8.834 :

10.604 I10.683 :π.420 :10.758 :10.239 I

2.1782.6042.6662.5672.4811.8391.7351.502 11.5991.507 11.549 11.176 <1.159 (1.8682.3402.8092.7142.1752.1522.3622.006

Fewt%)

1.4451.6291.7151.5411.5641.1191.019).9771.015).928).961).762).7311.1941.3531.6511.565.393.466.598.190

1.623 0.9991.315 (2.1451.8652.0552.4152.0812.0691.9831.6171.6201.9942.096>.O942.711J.7621.004 1'.723L644 1

9.652 2.47110.505 ;6.9634.8995.5875.4455.7586.4515.9295.2306.5334.4795.3655.795 ]5.048 ]5.453 ]4.718 15.170 16.000 16.082 16.833 16.961 1

t.728 1.654 1

).8151.4761.1701.2761.366.316.292.247.034.047.233.218.253.631.727.675.664.540.558.620.052

.207 0.748

.478 0.865

.453 0.902

.529 0.997

.646 1 .067

.522 0.916

.358 0.849

.489 0.955

.121 0.700

.424 0.853

.543 0.969

.242 0.780

.165 0.748

.156 0.709

.362 0.828

.553 0.992

.643 0.991

.837 1

.840 18.844 2.302 18.108 27.586 1

..113 1.939 1

7.960 2.028 17.488 17.524 17.839 1

.849 1

.905 1

.982 17.887 2.043 18.767 2.278 18.573 2.212 1

.240

.119

.347

.207

.211

.199

.204

.205

.287

.153

.475

.252

Ca(wt%)

26.70925.21624.42125.04125.29429.87530.03230.89830.50630.70329.88431.58532.24129.63426.39622.99826.35629.18527.39825.95630.15331.27732.90324.23929.50529.44824.73626.52527.33727.73128.68228.06127.55127.00826.83425.14425.03923.85924.55125.27726.13224.20729.66232.52031.76631.81230.90430.02430.89932.94029.40332.84731.94331.26332.51032.11232.90332.30130.76230.53328.81029.12530.09328.11628.29228.04928.46528.72528.23628.20027.05727.747

Ti(wt%)

0.1770.1880.1940.1830.1770.1200.1160.1020.1110.1090.1080.0810.0770.1220.1620.1920.1890.1600.1500.1620.1400.1110.0870.1480.1220.1460.1660.1530.1490.1430.1150.1150.1380.1500.1480.1880.1890.2060.1940.1860.1800.1940.1160.0790.1000.1010.1080.1230.1100.0930.1060.0760.0950.1070.0870.0830.0760.0860.1030.1130.1260.1260.1600.1480.1400.1460.1340.1350.1390.1400.1550.153

Mn(wt%)

0.0270.0310.0310.0250.0270.0230.0220.0210.0230.0230.0250.0220.0250.0270.0260.0320.0290.0300.0270.0300.0250.0230.0230.0260.0230.0280.0290.0260.0250.0250.0220.0230.0270.0270.0270.0360.0320.0310.0330.0300.0260.0290.0220.0200.0210.0220.0210.0240.0210.0230.0200.0170.0180.0200.0200.0200.0180.0210.0240.0270.0280.0280.0320.0260.0270.0270.0260.0240.0240.0250.0300.027

P(wt%)

0.0410.0490.0500.0470.0450.0420.0420.0410.0460.0430.0440.0400.0430.0460.0470.0460.0500.0530.0500.0480.0490.0490.0460.0440.0450.0530.0470.0530.0520.0500.0450.0450.0440.0480.0460.0470.0460.0490.0520.0560.0490.0540.0430.0370.0390.0420.0400.0440.0420.0440.0390.0410.0460.0530.0500.0430.0420.0490.0430.0420.0440.0440.0520.0470.0570.0540.0480.0490.0550.0430.0430.042

Chronostratigraphy from Clemens and Prell, pers. comm., March 1989.

422


APPENDIX BHole 722B Cores 1H and 2H Corrected for Salt Contribution and Dilution.


Depth aAge Ni Cr V Cu Zn Sr Rb Zr Ba Ce Nd Y U Th(mbsf) (k.y.) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm)

722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-01,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-02,722B-1H-03,722B-1H-03,722B-1H-03,722B-1H-03,722B-1H-03,722B-1H-03,722B-1H-O3,722B-1H-03,722B-1H-03,722B-1H-03,722B-1H-03,722B-1H-03,722B-1H-03,722B-1H-03,722B-1H-03,722B-1H-04,722B-1H-04,722B-1H-04,722B-1H-04,722B-1H-04,722B-1H-04,722B-1H-04,722B-1H-04,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-01,722B-2H-02,722B-2H-02,722B-2H-02,722B-2H-02,722B-2H-02,722B-2H-02,722B-2H-02,

06-08 cm16-18 cm26-28 cm36-38 cm46-48 cm56-58 cm66-68 cm76-78 cm86-88 cm96-98 cm106-108 cm116-118 cm126-128 cm136-138 cm146-148 cm06-08 cm16-18 cm26-28 cm36-38 cm46-48 cm56-58 cm66-68 cm76-78 cm86-88 cm96-98 cm106-108 cm116-118 cm126-128 cm136-138 cm146-148 cm06-08 cm16-18 cm26-28 cm36-38 cm46-48 cm56-58 cm66-68 cm76-78 cm86-88 cm96-98 cm106-108 cm116-118 cm126-128 cm136-138 cm146-148 cm06-08 cm16-18 cm26-28 cm36-38 cm46-48 cm56-58 cm66-68 cm76-78 cm06-08 cm16-18 cm26-28 cm36-38 cm46-48 cm56-58 cm66-68 cm76-78 cm86-88 cm96-98 cm106-108 cm116-118 cm126-128 cm136-138 cm146-148 cm06-08 cm16-18 cm26-28 cm36-38 cm46-48 cm56-58 cm66-68 cm

0.070.170.270.370.470.570.670.770.870.971.071.171.271.371.471.571.671.771.871.972.072.172.272.372.472.572.672.772.872.973.073.173.273.373.473.573.673.773.873.974.074.174.274.374.474.574.674.774.874.975.075.175.275.625.675.775.875.976.076.176.276.376.476.576.676.776.876.977.077.177.277.377.477.577.67

6.07.59.0

10.211.512.814.015.016.117.219.221.222.325.527.729.831.934.036.038.140.142.144.146.248.250.352.354.356.358.460.462.565.167.770.173.276.279.284.189.093.598.0

103.2107.5113.1116.8119.8122.8124.1126.0127.5129.2132.0135.8137.1138.2140.5142.6144.1145.2147.6149.4151.2152.7154.2156.2158.0159.5161.4163.2165.0166.8168.7170.7172.8

383633

48

39

52

57

62

62

61

76

59

59

59

57

61

60

55

55

58

48

52

60

59

57

52

51

48

48

47

58

71

62

61

77

59

50

47

53

51

48

49

40

44

59

55

48

44

55

61

62

64

60

55

56

56

56

61

71

74

75

72

74

75

80

83

78

72

71

66

60

67

70

64

39

30

40

59

50

79

86

91

99

99

92

99

94

87

95

100

90

85

90

96

76

80

82

76

90

82

72

69

73

68

85

118

110

110

119

102

74

63

81

74

66

71

51

71

89

67

47

37

77

87

92

104

90

87

90

94

89

90

92

112

125

113

119

123

143

133

133

122

107

103

102

97

103

96

37

39

41

51

37

49

51

56

63

52

54

52

57

50

52

60

53

53

52

59

44

43

47

46

55

41

41

46

43

40

54

66

64

63

65

55

49

46

53

50

46

51

35

50

57

51

51

44

56

54

54

57

50

56

54

59

61

61

60

76

77

74

77

69

81

66

80

69

66

60

59

67

67

69

24

22

25

21

24

20

20

22

25

24

41

21

21

21

20

20

18

20

23

20

24

19

23

20

26

23

23

17

17

21

21

22

21

23

22

25

28

25

23

22

23

26

20

24

28

27

30

25

22

19

22

22

20

19

21

21

20

20

19

22

20

19

24

24

22

22

22

24

25

23

22

20

21

19

38

34

32

40

33

39

42

49

48

45

62

42

40

47

43

45

46

41

44

43

37

40

44

43

43

39

39

35

37

36

44

52

45

43

50

43

40

35

42

37

38

43

33

38

46

52

48

45

41

42

41

42

40

40

42

41

46

40

42

49

51

45

47

52

50

53

52

50

47

47

48

45

48

48

1160

1218

1205

1114

1112

1043

960

932

948

926

942

964

937

933

956

896

953

938

962

891

1054

1024

1009

988

961

1082

1122

1107

1067

1155

1004

867

874

917

832

907

1064

1082

972

977

1130

1057

1144

1103

1023

1105

1142

1105

1040

1003

1043

980

982

978

968

939

969

944

920

784

756

795

755

788

769

802

740

825

883

858

940

870

866

870

16

13

13

23

19

26

28

28

33

29

29

28

31

28

29

32

30

29

28

32

24

22

25

24

28

22

20

24

23

21

29

39

35

33

33

35

23

21

28

25

19

25

17

24

30

22

20

18

30

30

28

30

26

27

28

30

30

29

29

38

40

34

36

38

41

39

41

35

32

32

30

33

32

32

44

36

34

53

46

57

65

68

73

67

68

68

69

63

64

74

70

66

63

70

58

59

61

60

64

55

53

54

52

52

65

82

76

73

78

70

59

51

61

55

47

59

44

53

64

55

46

42

65

63

63

68

61

63

64

70

67

70

67

82

88

78

78

82

84

78

86

78

70

68

65

69

70

68

754

799

693

325

309

286

295

306

224

304

283

254

237

319

311

283

305

286

321

197

272

343

447

450

359

470

467

315

307

410

298

244

251

291

373

296

372

441

283

372

501

575

492

419

560

703

1046

703

181

225

211

249

347

336

282

275

308

233

252

203

232

283

317

319

263

350

265

382

401

368

399

302

354

339

18

8

20

17

13

22

25

23

29

21

26

25

33

12

26

22

22

23

35

32

20

20

25

16

27

25

18

26

19

19

31

33

30

31

22

33

22

27

21

39

21

26

21

29

18

22

21

22

20

23

20

19

34

25

21

25

30

27

28

31

28

41

36

29

40

32

35

30

26

29

28

23

19

26

21

9

12

11

14

11

15

14

18

17

16

18

23

16

19

19

13

18

17

20

17

13

16

13

19

20

12

14

11

20

19

19

21

21

20

21

14

17

16

17

19

18

15

21

14

19

15

16

16

18

16

15

18

17

18

12

17

17

16

17

15

16

15

18

19

16

15

18

15

16

18

14

15

18

13

12

11

14

12

13

15

15

15

15

15

13

15

15

13

16

15

14

14

14

14

15

14

13

15

14

13

12

13

13

15

17

17

17

17

17

15

14

16

15

14

17

14

16

17

14

16

13

14

14

14

15

14

14

14

15

14

15

15

17

17

16

15

16

16

15

17

16

15

15

15

17

16

16

4.13 1.37

3.60

2.55

3.88

4.21

3.18

3.56

2.55

2.71

2.60

2.65

3.98

2.89

2.94

3.16

2.90

3.90

3.54

3.68

4.10

2.96

3.00

3.26

3.20

2.77

1.73

2.72

2.50

4.74

3.65

3.83

3.91

3.61

3.00

3.56

2.85

4.77

4.45

3.34

2.71

3.35

2.73

2.86

2.83

2.81

3.06

3.48

3.25

2.69

3.89

2.67

3.31

2.75

3.30

3.19

2.87

2.25

2.25

2.36

2.56

2.34

2.50

2.48

2.39

2.41

2.72

2.30

2.36

1.57

2.68

2.00

2.04

2.33

2.25

2.27

2.18

2.16

2.32

2.05

2.65

2.41

2.83

2.12

3.09

3.46

2.27

1.79

2.39

1.80

2.34

1.53

2.16

1.53

2.90

2.58

3.34 2.28

2.34

2.43

2.31

3.45

3.51

3.00

2.98

2.92

3.05

3.02

3.41

2.77

2.80

2.40

2.70

2.52

423


Appendix B (continued).


Depth aAge Ni Cr V Cu Zn Sr Rb Zr Ba Ce Nd Y U Th(mbsf) (k.y.) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm)

722B-2H-02, 76-78 cm722B-2H-02, 86-88 cm722B-2H-02, 96-98 cm722B-2H-02, 106-108 cm722B-2H-02, 116-118 cm722B-2H-02, 126-128 cm722B-2H-02, 136-138 cm722B-2H-02, 146-148 cm722B-2H-03, 06-08 cm722B-2H-03, 16-18 cm722B-2H-03, 26-28 cm722B-2H-03, 36-38 cm722B-2H-03, 46-48 cm722B-2H-03, 56-58 cm722B-2H-03, 66-68 cm722B-2H-03, 76-78 cm722B-2H-03, 86-88 cm722B-2H-03, 96-98 cm722B-2H-03, 106-108 cm722B-2H-03, 116-118 cm722B-2H-03, 126-128 cm722B-2H-03, 136-138 cm722B-2H-03, 146-148 cm722B-2H-04, 06-08 cm722B-2H-04, 16-18 cm722B-2H-04, 26-28 cm722B-2H-04, 36-38 cm722B-2H-04, 46-48 cm722B-2H-04, 56-58 cm722B-2H-04, 66-68 cm722B-2H-04, 76-78 cm722B-2H-04, 86-88 cm722B-2H-04, 96-98 cm722B-2H-04, 106-108 cm722B-2H-04, 116-118 cm722B-2H-04, 126-128 cm722B-2H-04, 136-138 cm722B-2H-04, 146-148 cm722B-2H-05, 06-08 cm722B-2H-05, 16-18 cm722B-2H-05, 26-28 cm722B-2H-05, 36-38 cm722B-2H-05, 46-48 cm722B-2H-05, 56-58 cm722B-2H-05, 66-68 cm722B-2H-05, 76-78 cm722B-2H-05, 86-88 cm722B-2H-05, 96-98 cm722B-2H-05, 106-108 cm722B-2H-05, 116-118 cm722B-2H-05, 126-128 cm722B-2H-05, 136-138 cm722B-2H-05, 146-148 cm722B-2H-06, 06-08 cm722B-2H-06, 16-18 cm722B-2H-06, 26-28 cm722B-2H-06, 36-38 cm722B-2H-06, 46-48 cm722B-2H-06, 56-58 cm722B-2H-06, 66-68 cm722B-2H-06, 76-78 cm722B-2H-06, 86-88 cm722B-2H-06, 96-98 cm722B-2H-06, 106-108 cm722B-2H-06, 116-118 cm722B-2H-06, 126-128 cm722B-2H-06, 136-138 cm722B-2H-06, 146-148 cm722B-2H-07, 06-08 cm722B-2H-07, 16-18 cm722B-2H-07, 26-28 cm722B-2H-07, 36-38 cm

7.777.877.978.078.178.278.378.478.578.678.778.878.979.079.179.279.379.479.579.679.779.879.97

10.0710.1710.2710.3710.4710.5710.6710.7710.8710.9711.0711.1711.2711.3711.4711.5711.6711.7711.8711.9712.0712.1712.2712.3712.4712.5712.6712.7712.8712.9713.0713.1713.2713.3713.4713.5713.6713.7713.8713.9714.0714.1714.2714.3714.4714.5714.6714.7714.87

175.2177.6180.0182.0184.1186.2187.7189.7191.1193.2197.6200.8204.3208.0211.5215.0218.5222.1225.8229.8233.4237.0239.0241.0242.9244.8246.3248.1249.8251.7253.2255.0256.6258.2259.8261.6263.2265.0266.5268.0271.5277.0281.5286.0289.0292.0295.0298.0302.0306.0310.0314.0318.0322.0326.0330.0331.5333.1334.6336.1337.6338.8340.8342.8344.8347.0349.2351.6353.7356.0360.5365.0

576573697148424044424738365157626366636951433738_5253525251454351515460646163616665453133373951424438343237333532323937454150594946464549455546

12796

1211089754575056525637315977

1079782818575543855907891879276637172827495928999

10211194573041445376635939333748404035404852596495718175716367617372

526966635753494845445239384656757749566355433640555355524752484252545359646780667261493739474339494133334247383335313637404151515046474950515653

192731262529262724262224202520252730282525252322292218232222191920202120192125232621232422212226272821212625272021242317201525172119211918171920

404552514941413741344039364241454645434444383433394339404040353438404142464546484942403231292836373727283134292736303525292738354135333435333436

870931903934940

1113113411791228125611711224127711671003842

1013116211211039120112521310944

10271105937

10201026105811171088107010801067977981954948991987987

122714421359136413331255134813981335142413521340143114411489138112831364126612711245118311401149116612051183120811151136

263232303023212018191714132329363426262823191519302530262524181925262634353435323628191418171819171814131619141212151919222228262325222325252929

946774706845444044424635334857717059565955473939756068626258495459606273757677738077614349495460556048485356525149535658636275716973686571707373

259359424518582645540521550548687737714446281265323516380421524573602326242417263379376398450454369402375262209259356364330383514498242348253493439605383368425391524502582449301120118183186222334319351341360227237260

2527342125292214122529156

1227252016302731201723193428292616252216252339272415232920232122111210191821222012146

12251817261717311620243121232323

17171415192116151720181611151716121612181816141213191213151514161414171516161816151721201515138

11121716167

161112181819131115161511131613141319

151618171716161414131412121313161716151617151311141414131414131213131315171717181915141313141515121413131515131212141210111214141514141213121414

4.11

3.04

3.07

2.39

2.81 —

2.28 —

2.73 —

3.13

1.81

1.27

2.40

3.20 2.70

4.18

3.62

2.41

2.58

2.13

1.37

— Missing data or no data available.a Chronostratigraphy from Clemens and Prell, pers. comm., March 1989.

424


APPENDIX CHole 724C Major Element Analyses. Corrected for Salt Contribution and Dilution.


724C-1H-01, 25-27 cm724C-1H-01, 45-47 cm724C-1H-01, 65-67 cm724C-1H-01, 85-87 cm724C-1H-01, 105-107 cm724C-1H-01, 125-127 cm724C-1H-01, 145-147 cm724C-1H-02, 15-17 cm724C-1H-02, 35-37 cm724C-1H-02, 55-57 cm724C-1H-02, 75-77 cm724C-1H-02, 95-97 cm724C-2H-01, 10-12 cm724C-2H-01, 25-27 cm724C-2H-01, 45-47 cm724C-2H-01, 65-67 cm724C-2H-01, 85-87 cm724C-2H-01, 105-107 cm724C-2H-01, 125-127 cm724C-2H-01, 145-147 cm724C-2H-02, 15-17 cm724C-2H-02, 35-37 cm724C-2H-02, 55-57 cm724C-2H-02, 75-77 cm724C-2H-02, 95-97 cm724C-2H-02, 115-117 cm724C-2H-02, 135-137 cm724C-2H-03, 05-07 cm724C-2H-03, 25-27 cm724C-2H-03, 45-47 cm724C-2H-03, 65-67 cm724C-2H-03, 85-87 cm724C-2H-03, 105-107 cm724C-2H-03, 125-127 cm724C-2H-03, 145-147 cm724C-2H-04, 15-17 cm724C-2H-04, 35-37 cm724C-2H-04, 55-57 cm724C-2H-04, 75-77 cm724C-2H-04, 95-97 cm724C-2H-04, 115-117 cm724C-2H-04, 135-137 cm724C-2H-05, 05-07 cm724C-2H-05, 25-27 cm724C-2H-05, 45-47 cm724C-2H-05, 65-67 cm724C-2H-05, 85-85 cm724C-2H-05, 105-107 cm724C-2H-05, 125-127 cm724C-2H-05, 145-147 cm724C-2H-06, 15-17 cm724C-2H-06, 35-37 cm724C-2H-06, 55-57 cm724C-2H-06, 75-77 cm724C-2H-06, 95-97 cm724C-2H-06, 115-117 cm724C-2H-06, 135-137 cm724C-2H-07, 05-07 cm724C-2H-07, 25-27 cm724C-2H-07, 45-47 cm724C-2H-07, 60-62 cm724C-3H-01, 25-27 cm724C-3H-01, 45-47 cm724C-3H-01, 65-67 cm724C-3H-01, 85-87 cm724C-3H-01, 105-107 cm724C-3H-01, 125-127 cm724C-3H-01, 145-147 cm724C-3H-02, 15-17 cm724C-3H-02, 35-37 cm724C-3H-02, 55-57 cm724C-3H-02, 75-77 cm724C-3H-02, 95-97 cm724C-3H-02, 115-117 cm724C-3H-02, 135-137 cm724C-3H-03, 05-07 cm724C-3H-03, 25-27 cm

Depth(mbsf)

0.250.450.650.851.051.251.451.651.852.052.252.452.903.053.253.453.653.854.054.254.454.654.855.055.255.455.655.856.056.256.456.656.857.057.257.457.657.858.058.258.458.658.859.059.259.459.659.85

10.0510.2510.4510.6510.8511.0511.2511.4511.6511.8512.0512.2512.4012.4512.6512.8513.0513.2513.4513.6513.8514.0514.2514.4514.6514.8515.0515.2515.45

aAge(k.y.)

6.17.58.8

10.111.512.814.115.516.818.119.520.823.825.327.629.832.134.336.638.841.143.345.547.850.052.354.556.859.061.163.265.367.469.571.673.775.877.980.086.092.098.0

104.0110.0116.0122.0123.2124.4125.5126.7127.9129.1130.3131.5132.6133.8135.0137.8140.5143.3146.1146.7148.8151.6154.4157.2159.9162.7165.5168.2171.0172.5174.0175.5177.0178.5180.0

Si(wt%)

11.9410.6612.1211.9311.7413.9814.0814.1214.4214.6113.9014.0413.8814.2214.0215.4615.1114.8019.8415.5616.0015.1914.8113.2514.4215.7413.5314.4714.0613.6813.3513.6614.8614.3715.6713.4412.299.53

11.5712.1510.509.92

11.1511.0610.9612.2512.4212.9713.8312.4214.0114.2214.0014.2714.3814.8414.9115.1815.3214.8815.0214.8813.9913.8814.1213.8814.1413.9413.7213.8214.3014.5013.5314.6814.7914.2714.79

Al(wt%)

2.121.972.232.222.292.642.732.752.862.992.902.982.642.872.823.202.992.884.223.083.173.062.932.762.913.112.922.972.892.842.802.762.952.853.242.802.451.942.352.452.192.062.222.212.122.352.332.552.692.472.672.762.872.962.933.063.033.073.023.063.113.082.922.952.982.922.952.942.952.942.973.042.813.043.082.983.12

Fe(wt%)

0.900.870.980.981.131.281.341.421.481.601.511.711.301.481.541.731.561.472.341.621.621.651.58

:

(

.47

.55

.641.57.64.50.54.57

1.43.47.47.75.41.15

).84.13.15.03

0.931.001.060.961.071.061.221.291.271.321.361.531.571.571.591.491.531.511.621.581.581.501.691.551.511.551.561.631.601.591.591.551.631.631.65.70

Mg(wt%)

1.120.991.501.511.692.042.142.092.182.252.222.222.022.032.072.312.231.952.762.222.252.112.031.852.062.122.052.311.362.102.391.892.101.972.121.841.451.011.451.101.281.181.501.331.361.701.621.972.072.012.092.142.422.372.392.592.232.372.272.332.322.272.292.352.362.312.292.312.362.262.292.372.232.372.342.282.37

Ca(wt ft)

21.9724.6322.7822.6522.7620.8519.9519.1319.2518.6419.6519.2820.7819.6719.4617.1419.0019.7112.1519.1919.0617.8518.6020.3619.4418.6920.1319.8620.9520.5120.4119.8920.3819.7417.4020.4222.4425.6823.1523.0224.3725.6225.5224.6823.8322.8220.1421.3820.7021.0120.7120.4020.0519.7819.5718.0918.9019.2418.8618.5718.7318.4619.8519.5219.5619.7919.8619.7919.8019.9619.6219.4718.8519.1118.7118.2618.63

Na(wt%)

1.050.720.840.870.810.900.810.880.930.840.790.850.830.861.021.110.820.811.210.891.010.900.930.770.961.000.860.820.220.941.170.850.920.820.890.960.890.850.890.530.840.720.970.730.730.850.880.880.890.550.910.860.880.910.731.180.830.790.920.950.820.920.890.820.750.790.870.800.810.760.860.770.870.850.860.850.75

K(wt


Appendic C (continued).


724C-3H-03, 45-47 cm724C-3H-03, 65-67 cm724C-3H-03, 85-87 cm724C-3H-03, 105-107 cm724C-3H-03, 125-127 cm724C-3H-03, 145-147 cm724C-3H-04, 15-17 cm724C-3H-04, 35-37 cm724C-3H-04, 55-57 cm724C-3H-04, 75-77 cm724C-3H-04, 95-97 cm724C-3H-04, 115-117 cm724C-3H-04, 135-137 cm724C-3H-05, 05-07 cm724C-3H-05, 25-27 cm724C-3H-05, 45-47 cm724C-3H-05, 65-67 cm724C-3H-05, 85-87 cm724C-3H-05, 105-107 cm724C-3H-05, 125-127 cm724C-3H-05, 145-147 cm724C-3H-06, 15-17 cm724C-3H-06, 35-37 cm724C-3H-06, 55-57 cm724C-3H-06, 75-77 cm724C-3H-06, 95-97 cm724C-3H-06, 115-117 cm724C-3H-06, 135-137 cm724C-3H-07, 05-07 cm724C-3H-07, 25-27 cm724C-3H-07, 45-47 cm724C-3H-07, 65-67 cm724C-4H-01, 13-15 cm724C-4H-01, 25-27 cm724C-4H-01, 45-47 cm724C-4H-01, 65-67 cm724C-4H-01, 85-85 cm724C-4H-01, 105-107 cm724C-4H-01, 125-127 cm724C-4H-01, 145-147 cm724C-4H-02, 15-17 cm724C-4H-02, 35-37 cm724C-4H-02, 55-57 cm724C-4H-02, 75-77 cm724C-4H-02, 95-97 cm724C-4H-02, 115-117 cm724C-4H-02, 135-137 cm724C-4H-03, 05-07 cm724C-4H-03, 25-27 cm724C-4H-03, 45-47 cm724C-4H-03, 65-67 cm724C-4H-03, 85-87 cm724C-4H-03, 105-107 cm724C-4H-03, 125-127 cm724C-4H-03, 145-147 cm724C-4H-04, 15-17 cm724C-4H-04, 35-37 cm724C-4H-04, 55-57 cm724C-4H-04, 75-77 cm724C-4H-04, 95-97 cm724C-4H-04, 115-117 cm724C-4H-04, 135-137 cm724C-4H-05, 05-07 cm724C-4H-05, 25-27 cm724C-4H-05, 45-47 cm724C-4H-05, 65-67 cm724C-4H-05, 85-87 cm724C-4H-05, 105-107 cm724C-4H-05, 125-127 cm724C-4H-05, 145-147 cm724C-4H-06, 15-17 cm724C-4H-06, 35-37 cm724C-4H-06, 55-57 cm724C-4H-06, 75-77 cm724C-4H-06, 95-97 cm724C-4H-06, 115-117 cm724C-4H-06, 135-137 cm724C-4H-07, 15-17 cm

Depth(mbsf)

15.6515.8516.0516.2516.4516.6516.8517.0517.2517.4517.6517.8518.0518.2518.4518.6518.8519.0519.2519.4519.6519.8520.0520.2520.4520.6520.8521.0521.2521.4521.6521.8321.8521.9522.1522.3522.5522.7522.9523.1523.3523.5523.7523.9524.1524.3524.5524.7524.9525.1525.3525.5525.7525.9526.1526.3526.5526.7526.9527.1527.3527.5527.7527.9528.1528.3528.5528.7528.9529.1529.3529.5529.7529.9530.1530.3530.5530.85

aAge(k•y )

181.5183.0185.1187.2189.3191.5193.6195.7197.8199.9202.0204.2206.3208.4210.5212.6214.7216.8219.0221.1223.2225.3227.4229.5231.7233.8235.9238.0239.2240.3241.5242.5242.6243.2244.4245.5246.7247.8249.0254.4259.9265.3270.7276.1281.6287.0289.2291.4293.6295.8298.0300.2302.4304.6306.8309.0311.2313.4315.6317.8320.0322.2324.4326.6328.8331.0332.7334.3336.0337.7339.3341.0342.7344.3346.0349.3352.3355.6

Si(wt%)

15.8014.9114.8816.7919.3415.1715.5015.4817.2115.3115.3415.2616.1915.8714.0914.1114.5313.2013.5414.1514.6214.219.109.90

11.256.85

10.4111.2912.4212.7312.8812.0212.4112.0412.8014.7915.2115.6014.1016.1014.8914.6714.6414.1214.5714.5112.7313.0112.8012.6312.2412.0013.1312.3013.9612.1810.7210.9011.0511.9511.9610.7310.508.26

11.6312.6511.5412.0411.4412.7112.7413.8413.8814.1815.0214.3014.2413.76

Al(wt%)

3.443.323.253.654.173.323.333.383.883.383.323.403.603.423.103.133.122.903.013.043.113.102.022.172.461.572.392.582.722.672.712.532.402.382.512.973.163.273.033.223.033.053.093.033.143.132.782.852.722.682.662.572.792.612.862.532.182.262.222.292.362.202.121.332.182.422.292.462.322.512.562.692.722.732.932.882.832.78

Fe(wt%) 0

1.911.841.862.002.341.901.861.922.141.881.831.912.021.971.751.731.711.681.701.641.681.701.011.151.290.79 (1.301.431.451.401.421.281.151.201.261.50 :

:

1.68 :

Mgvt%)

2.222.502.542.693.252.532.482.492.792.452.442.552.502.382.282.142.212.142.092.142.222.211.211.321.54).971.66.77.82.83.75.63

1.58.54.66

>.O9>.26

1.73 2.361.68 :1.69 :1.64 :i.72 ;

>.09>.34>.17>.18

.63 2.21

.61 2.18

.81 2.271.72 2.271.54 2.101.54 2.151.451.391.421.381.451.301.391.231.021.061.000.98 ]1.10 ]1.040.99 10.86 11.08 11.14 11.071.23 ]

.11 ]

.26 1

.90

.97

.99

.83

.79

.61

.80

.53

.26

.42

.32

.30

.45

.36

.25

.19

.58

.72

.67

.92

.76

.98.27 2.02.37 2.04.34 2.07.32 2.06.43 :-.18.45 2.02

1.421.52 1

.99

.96

Ca(wt%)

18.3217.4617.9915.1621.6817.8717.8017.8414.6917.3618.1017.4916.0916.8919.3719.2519.0619.1219.7119.0418.9818.9525.4624.0022.6628.2723.3822.5721.7021.3021.1421.8322.3722.6421.2319.1718.1916.8318.9217.1318.4218.2519.0919.3819.1418.9821.2721.0521.2321.5221.7121.3622.4620.7021.3722.6424.2526.5924.1823.3223.1023.9318.8926.4223.3222.1923.4423.0024.6621.9421.7420.7720.6720.0919.6019.4820.0020.31

Na(wt%)

0.560.770.820.981.270.880.960.841.010.740.900.920.931.031.000.820.860.780.890.920.830.970.700.720.830.630.690.720.700.840.770.830.780.730.780.900.850.960.881.000.900.880.770.820.780.930.760.760.820.770.750.770.830.760.820.840.650.790.760.700.740.800.760.630.730.800.740.680.750.650.760.810.880.800.930.910.870.80

K(wt%)

0.940.930.911.021.170.930.940.931.080.950.920.940.970.930.840.850.850.830.820.810.850.830.530.580.660.410.660.710.750.740.730.680.650.650.720.830.890.930.850.900.850.840.870.850.880.880.790.820.750.770.770.750.750.710.770.680.590.600.610.630.650.600.570.470.650.660.630.670.630.700.730.790.780.790.840.820.800.80

Ti(wt%)

0.2690.2630.2630.2910.3210.2650.2700.2720.3080.2650.2670.2690.2780.2800.2510.2510.2480.2590.2450.2470.2560.2480.1620.1760.1970.1280.1910.2040.2200.2270.2180.2070.2040.2010.2190.2490.2600.2650.2420.2810.2550.2510.2510.2450.2510.2540.2260.2300.2210.2200.2160.2120.2270.2110.2300.2040.1760.1750.1840.1900.1970.1780.1710.1410.1920.2000.1910.2070.1890.2080.2140.2260.2240.2320.2390.2390.2380.239

Mn(wt%)

0.0440.0380.0410.0420.0510.0420.0410.0440.0460.0420.0450.0440.0390.0410.0400.0380.0400.0380.0410.0340.0380.0340.0250.0240.0270.0200.0280.0310.0350.0350.0310.0280.0280.0290.0310.0340.0380.0320.0320.0350.0350.0320.0390.0330.0380.0360.0330.0350.0310.0340.0330.0310.0310.0310.0310.0250.0240.0250.0240.0250.0250.0250.0230.0220.0260.0320.0300.0310.0260.0320.0330.0330.0340.0350.0360.0360.0340.031

P(wt


Appendic C (continued).


724C-4H-07, 35-37 cm724C-4H-07, 55-57 cm724C-4H-07, 75-77 cm724C-5H-01, 10-12 cm724C-5H-01, 25-27 cm724C-5H-01, 45-47 cm724C-5H-01, 65-67 cm724C-5H-01, 85-87 cm724C-5H-01, 105-107 cm724C-5H-01, 125-127 cm724C-5H-01, 145-147 cm724C-5H-02, 15-17 cm724C-5H-02, 35-37 cm724C-5H-02, 55-57 cm724C-5H-02, 75-77 cm724C-5H-02, 95-97 cm724C-5H-02, 115-117 cm724C-5H-02, 135-137 cm724C-5H-03, 05-07 cm724C-5H-03, 25-27 cm724C-5H-03, 45-47 cm724C-5H-O3, 65-67 cm724C-5H-03, 85-87 cm724C-5H-03, 105-107 cm724C-5H-03, 125-127 cm724C-5H-03, 145-147 cm724C-5H-04, 15-17 cm724C-5H-04, 35-37 cm724C-5H-04, 55-57 cm724C-5H-04, 75-77 cm724C-5H-04, 95-97 cm724C-5H-04, 115-117 cm724C-5H-04, 135-137 cm724C-5H-05, 05-07 cm724C-5H-05, 25-27 cm724C-5H-05, 45-47 cm724C-5H-05, 65-67 cm724C-5H-05, 85-87 cm724C-5H-05, 105-107 cm724C-5H-05, 125-127 cm724C-5H-05, 145-147 cm724C-5H-06, 15-17 cm724C-5H-06, 35-37 cm724C-5H-06, 55-57 cm724C-5H-06, 75-77 cm724C-5H-06, 95-97 cm724C-5H-O6, 115-117 cm724C-5H-06, 135-137 cm724C-5H-07, 05-07 cm724C-5H-07, 25-27 cm724C-5H-07, 45-47 cm724C-5H-07, 60-62 cm724C-6X-01, 05-07 cm724C-6X-01, 25-27 cm724C-6X-01, 45-47 cm724C-6X-01, 65-67 cm724C-6X-01, 85-87 cm724C-6X-01, 105-107 cm724C-6X-01, 125-127 cm724C-6X-01, 145-147 cm724C-6X-02, 15-17 cm724C-6X-02, 35-37 cm724C-6X-02, 55-57 cm724C-6X-02, 75-77 cm724C-6X-02, 95-97 cm724C-6X-02, 115-117 cm724C-6X-02, 135-137 cm724C-6X-03, 05-07 cm724C-6X-03, 25-27 cm724C-6X-03, 45-47 cm724C-6X-03, 65-67 cm724C-6X-03, 85-87 cm724C-6X-03, 105-

Date post:	29-Jan-2021
Category:	Documents
Upload:	others
View:	0 times
Download:	0 times

23. THE INORGANIC GEOCHEMICAL RECORD OF THE ......racy for major and minor elements. Element Si Al...

Documents