Synchronous variations in the content of magnetic minerals and planktonic-foraminiferal δ13C in deep-sea sediments

BMAEO ELSEVIER

",OORAPMY

~ ECOl!lGV

Palaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215

Synchronous variations in the content of magnetic minerals and planktonic-foraminiferal l5 13C in deep-sea sediments Takaharu Sato a, Nobuyuki Nakai b, Yasutoshi Shirai c, Kazuo Kobayashi d b

a Faculty of Engineering, Niigata University, Ikarashi, Niigata 950-21, Japan Geoscience Laboratory, Gen-emonshinden 22-19, Ueda, Tenpakucyo, Tenpaku-ku, Nagoya, 468, Japan C Mie General Education Center, Otani-cho 12, Tsu, Mie 514, Japan d Japan Marine Science and Technology Center, Natsushima-cho 2-15, Yokosuka 237, Japan

Received 6 April 1993; revised and accepted 31 May 1994

Abstract A correlation between magnetic mineral contents and b13 C was obtained using two deep-sea sediment cores having distinctly different sedimentation rates, taken from the western equatorial Pacific. It was inferred that the fluctuations in the content of magnetic minerals, predominantly of bacterial origin, are caused mostly by variations in CaC03 dissolution. The correlation seems to originate from changes in the vertical distribution of nutrients and carbon with isotopic fractionation.

1. Introduction Magnetic minerals in deep-sea sediments are important not only as carriers of the natural remanent magnetization but also as indicators of environmental changes. The relationship between variations in the abundance of magnetic minerals and the abundance of CaC0 3 in Quaternary deepsea sediment cores has been discussed by a number of authors. The correlation to variations in 15 180 has also been examined as has local or global changes in the environment accompanying the glacial cycle (Kent, 1982; Niitsuma et a1., 1991). On the other hand, attention has not been given to the relationship to variations in J 13 c. Nor, in most cases, has the origin of the magnetic minerals been examined. It is well known that the CaC03 dissolution intensifies with depth, especially at and below the lysocline. Cyclic variations in the intensity of CaC03 dissolution have been recognized in the central equatorial Pacific (Farrell and Prell, 1989) 0031-0182/95/$9.50 © 1995 Elsevier Science B.V. All rights reserved SSDI 0031-0182(95)00049-E

and in the western equatorial Pacific (Wu et a1., 1991). Identification of the isotopic stages gives a detailed time scale for cores with no severe CaC0 3 dissolution. However, the identification of the isotopic stages is generally difficult for cores taken at a depth of more than 4000 m. At these water depths it has been shown that the relative time scales can instead be obtained by matching curves for the content of bacterial magnetite records (Sato et a1., 1993). In this article we examine the correlation between variations in the saturation isothermal remanent magnetization (SIRM) intensity records, representing mostly the content of bacterial magnetite, and J13 C records of two deep-sea cores sampled at these water depths in the Melanesia Basin.

2. Samples The samples examined in this study were taken from cores about 10m long, KH 73-4-7 and KH

T. Sato et al.jPalaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215

200

73-4-8 collected from two sites 500 km apart in the Melanesia Basin, western equatorial Pacific Ocean (2°4I'N, 164°50'E, 4160 m deep and 1 33'S, 167°39'E, 4000 m deep, respectively), A series of paleomagnetic studies (Kawai et aI., 1976, 1977; Sueishi et aI., 1979; Sato and Kobayashi, 1989), as well as a study of rock magnetism (Yoshida and Katsura, 1985), were performed on these two cores. The chronology of each core was established using magnetic reversals, the paleontological datum of the last appearance of Pseudoemilliania lacunosa (ca. 0.474 Ma), and electron spin resonance (ESR) measurements as shown in Table l. Except for confirmation of 0 age at the top of core KH 73-4-7, the ages estimated using ESR were used only to check the results obtained by the other methods. 0

The variations in SIRM of the two cores produced in a static field of 0.90 T are closely correlated (Sato and Kobayashi, 1989). As shown in Fig. I, there is similarity between both the pattern

of variations in SIRM in the two cores, and also in the absolute values. This is observed even in the interval around 0.6 Ma in which the sedimentation rate of KH 73-4-8 is about 3 times as fast as that of KH 73-4-7. The SIRM intensity corresponds to the abundance of magnetic minerals in the sediment, unless there is a significant variability of grain size and/or magnetic minerals. The variability has been shown to be negligible for these cores (Sueishi, 1979; Yoshida and Katsura, 1985). Therefore, at the sites of higher sedimentation rates the supply of magnetic minerals is also higher. The magnetic minerals extracted from the cores were examined with a transmission electron microscope (TEM). They were classified into two groups according to grain size (Akai et aI., 1991). Coarse fractions 2-10 mm diameter are composed of iron with varying titanium contents. The other fractions are sub-,um particles composed of nearly entirely pure magnetite. Octahedral grains, with a very restricted variation in size corresponding to that of single-domain magnetite, are predominant. There are four types of octahedral, cuboidal and/or rectangular shapes, hexagonal prism and teardropshaped pure magnetite grains of single domain size

Table 1 Stratigraphic control points and their estimated ages in both core Age (kyr)

o 62 224 282 457 474 647 730 900 970 1085 1268 1392 1540 1670 1870 2120 2190

KH 73-4-7

KH 73-4-8

Depth (cm)

Depth (cm)

o 0 23 50 192 116

261 357 406

807 886 1022

465 532 623 673 714 763 792 821 873 885 889

Methods

Reference

ESR dating SIRM matching SIRM matching SIRM matching SIRM matching the last appearance of P. lacunosa SIRM matching B-M transition upper Jaramillo transition lower J aramiIIo transition SIRM matching SIRM matching SIRM matching SIRM matching upper Olduvai transition lower Olduvai transition SIRM matching (linear extrapolation)

Sato, 1982

Takayanagi et aI., 1979: Gartner, 1977

Mankinen and Dalrymple, 1979 Mankinen and Dalrymple, 1979 Mankinen and Dalrymple, 1979

Mankinen and Dalrymple, 1979 Mankinen and Dalrymple, 1979

T. Sato et al./Palaeogeography, Palaeoclimatology, Palaeoecology 113 ( 1995) 199-215 - - 4-7

zo -
201 - - 4-8

180

I-<

8

0

r:-<

~

*1O. 3 emu/gr

6 4

1.6

1.8 I

8 1

2

3

4

5

6

7

8

AGE (Ma) I

I

I

4-7 DEPTH (M) 4-8 DEPTH (M)

Fig. L Variations in paleomagnetic declination and intensity of SIRM and in isotopic ratios with ages in KH 73-4-7 (heavy line) and KH 73-4-8 (light line). The ages for KH 73-4-7 are assigned by magnetostratigraphy (Mankinen and Dalrymple, 1979), paleontological datum plane of the last appearance of P. lacunosa (ca. 0.474 m.y.) and the ESR study for the top of the core. The ages for KH 73-4-8 are assigned by correlation of SIRM with KH 73-4-7, accompanied with above mentioned methods. The detailed description has been shown in a separate paper.

that have previously been identified as biogenic magnetite. On the basis of their characteristic shape, size distribution and chemical composition, we concluded that the sub-Jim particles are bacterial in origin. Rock magnetic experiments showed that grain-size variations of the magnetic minerals in the two cores are negligible (Sueishi et aL, 1979), and that the magnetic grains are mostly composed of single domain or pseudo-single domain-sized magnetite grains (Yoshida and Katsura, 1985). It can, therefore, be concluded that the majority of magnetic minerals contained in these deep-sea sediments a:re of bacterial origin (Sato et aL, 1993). The CaC03 content of core KH 73-4-7 was measured (Sato et aL, 1993). A clear inverse

correlation was found between CaC0 3 content and the intensity of SIRM as shown in Fig. 2. The abundance of magnetic minerals may vary as the result of: (1) changes in the input of non-biogenic magnetic minerals, (2) changes in the rate of dissolution of CaC03 which results in concentration of the magnetic phases, and (3) changes in biological productivity at the sea surface. The latter affects both the vertical flux of CaC0 3 and the production rate of benthic magnetotactic bacteria. Small fluctuations as little as 5% in CaC03 contents have been reported in cores taken from the Ontong Java Plateau close to the present coring sites but shallower than the lysocline (Berger et aL, 1991; Tauxe and Wu, 1990), implying that larger fluctuations in CaC0 3 contents at greater water

202

T Sato et al./Palaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215

7r------------, ~6

....

•

Cl

~5

E

'"

Q)

4

••

~ 3

r

~ 2

r

x

c:

• I

. :.III"

•

Ci5 1

o L-"--: I~ 1 -I, -...I---,I......IL..-,IL-.L..-..L-I o 20 40 60 80 100 CaC0 (%) 3

Fig. 2. SIRM

VS.

CaC0 3 for KH 73-4-7.

depths may have resulted from the dissolution ofCaC03 · Characteristic patterns of SIRM intensity in core KH 73-4-7 also seem to indicate that intensity variations were caused by variations in the amount of dissolution of CaC0 3 (Sato et aI., 1993). If the SIRM intensity depends only on the intensity of CaC0 3 dissolution, the ratio of the maximum SIRM to the minimum SIRM would be less than l/(1-r), where r is a content of CaC0 3 when CaC03 was not dissolved. The actual ratio of the maximum SIRM intensity to its minimum value did not exceed 8, its value being restricted by the total content of CaC0 3 at the surface (",87%). Furthermore, as shown in Fig. 1, the peaks in the variations of SIRM are steeper and sharper than their troughs. Such a pattern of SIRM variations can be explained by the fact that the lower SIRM values appear generally more frequently than the higher values, which corresponds to a model showing that the magnetic phases are condensed by dissolution of variable degrees. Analysis of the dissolution index, which is the ratio of fragmented to unfragmented tests of planktonic foraminifera (Oba and Ku, 1977; Ku and Oba, 1978), shows that the index covaries with fluctuations of the CaC0 3 content (Oba, pers. comm.). We thus conclude that a dominant factor controlling the intensity of SIRM is the degree of CaC0 3 dissolution.

the sediments were also investigated by examining the relationship between SIRM and the 13C/12C ratios in the calcium carbonate of planktonic foraminifera in the same specimens. Globorotalia tumida was the only continuously present form with sufficient quantity for our isotopic measurements throughout the core, so it was selected for isotopic analysis. Although G. tumida is not a preferred species for isotopic analyses, it has been used in other studies with adequate results (Rea et aI., 1986). The samples for isotopic measurements were taken from the entire length of core KH 73-4-7, and from a limited range of depth in core KH 73-4-8. They were washed through a 150,um sieve, and dried in an oven at 80°e. Following the approach of Estonia et ai. (1953), hand-picked monospecific samples, weighing about 20 mg were heated in a stream of purified helium for 60 min in an oven at 470°C to eliminate the influence of organic matter. They were reacted with 100% H 3P0 4 acid. The carbon dioxide gas thus obtained was isotopically analyzed. The predominant period of variation of 6180 and 613 C is similar to that of the SIRM. The isotopic fluctuations between the two cores show a positive correlation, except for horizons around the Brunhes-Matuyama boundary. Fig. 3 shows the fluctuations of SIRM and 6 13 C in each core. Within each core these two quantities have a moderate positive correlation except for a short duration around the Brunhes-Matuyama boundary (0.7 Ma). In particular, the correlations of SIRM and 613 C for a portion prior to 0.90 Ma and one later than 0.68 Ma in core KH 73-4-7, are highly significant, having error levels which are IY. = 0.5% (r = 0.380, n = 60) for the first portion and IY.= 0.0002% (r= 0.433, n= 116) for the second (Table 2). The correlation for the portion prior to 0.90 Ma in core KH 73-4-8 is also significant, having an error level at IY. = 0.2% (r= 0.716, n= 16).

5. Discussion 13

4. Correlation between SIRM and t5 C The effects of environmental changes on the content of bacterial magnetite contained in

The 6180 values of planktonic foraminifera from these cores do not exhibit typical late Pleistocene oxygen isotope variations (Fig. 1), so it is difficult

T Sato et al./Palaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215

203

KH 73-4-7

6

SIRM3 (x IO· emu/gr)

4

2

KH 73-4-8 (xlO· emu/gr) , . . . - - - - ------~ SIRM_/i13 e 6 (%0) 3 3

2 O~----~II·-~---L-~

5

6

DEPTH(m)

Fig. 3. Correlation of SIRM intensity (light line) with 013C curve (heavy line) with depths of the two cores. Black and white stripes indicate normal (black) and reversed (white) periods of paleomagnetic polarity. Shaded stripes are transient directions between reversals. Table 2 Correlation coefficients (r) between SIRM and 013C, and the p-values for the null hypothesis, r= 0 Time range

Core

Number of samples

SIRM-013C

p-value

(Ma) 0-0.68 0.68-0.90 0.90-2.20

4-7 4-7 4-8 4-7 4-8

116 43 28 60 16

0.433 -0.045 0.120 0.380 0.716

<0.0002%

<0.5% <0.2%

to identify uniquely the isotopic stages for the whole upper Pleistocene period. Close correlation of the variations in SIRM between cores taken from two sites 500 km apart suggest a low possibility of discontinuities, such as land slides and/or hiatus, as the cause. It is well understood that partial dissolution affects the oxygen isotopic composition of foraminiferal assemblages (Wu and Berger, 1989). In addition, mixing by benthic organisms may somewhat affect the sharp pattern of the rapid decreases at glacial-interglacial transitions in 618 0 in cores

with low sedimentation rates. On the other hand, although there is no report that shows partial dissolution having any effect on carbon isotopic composition, a dissolution experiment on calcium carbonate of planktonic foraminifera, G. tumida, showed that its dissolution from 7.5 mg to 1.3 mg caused only a slight increase (0.14%0) in 613 C and large decrease (-0.91%0) in 618 0 (Oba, pers. comm.). Such a small change in 613 C due to dissolution is negligible compared to its observed variations. Isotopic examinations of individual shells of G. tumida (Killingley et aI., 1981) revealed that 618 0 has a large inter-shell variability, and that in the case of 613e it is significantly small: the standard deviations are 0.53%0 and 0.17%0, respectively. They suggested that the reduced variability of G. tum ida, a deep-living foraminifera, supports the notion that 613 C varies mainly in surface waters, and not at depth. The reliability of the 613e records may also be tested by comparing them with other 613e records collected from different sites. The 613e variations in the portion upper 50 cm in core KH 73-4-7 appear to correlate to a 613 C record in core V19-30 taken from the eastern equatorial

204

T Sato et ai/Palaeogeography, Palaeoclimatology, Palaeoecology J13 (1995) 199-215

Pacific (Shackleton et aI., 1983), if the depth of 50 cm in core KH 73-4-7 corresponds to around 130 kyr. Difference in reliability between the <5 180 and <5 13 C records of the present study may exist because of the difference, to some extent, in the inter-shell variability in the isotopic ratios and by the difference in the factors reflected in the isotopic ratios. As we have previously shown, the influence of the CaC0 3 dissolution to <5 13 C is not thought to be significant. Thus, the correlation between <5 13 C values and the content of magnetic minerals in the sediments at deep-sea floor may arise as follows; first, through sinking materials transferring information about environmental variations at the sea surface to the deep sea, and/or second, through variations in ocean circulation which are reflected in both records. Sinking materials which could possibly connect the records are the coarse fractions of magnetic minerals and biogenic materials. The notion that the sinking materials are coarse magnetic grains does not correlate directly with the results of rock magnetic studies. In these the carriers of SIRM have been shown to be mostly single domain or pseudo-single domain-sized magnetite grains (Yoshida and Katsura, 1985) and grain-size variations of magnetic grains are negligible (Sueishi et aI., 1979). A recent study shows that phytodetrital aggregates from euphotic waters may be sedimented rapidly on the deep-sea floor (Billett et aI., 1983; Lampitt, 1985). This has been recognized as probably the most important source of energy for the deep-sea ecosystem (Fowler et aI., 1986; Lochte and Turley, 1988; Gooday, 1988). The productivity of the magneto tactic bacteria may thus reflect the flux of organic matter brought from the sea surface (Bloemendal et aI., 1988). On the other hand the vertical distributions of biologically utilized elements such as C and P, in the sea, reflect the biological cycling of organic matter as modified by water circulation patterns. Photosynthetic organisms take up 12C in preference to 13C and they also efficiently concentrate nutrients such as P and N. Hence surface waters are left with a high <5 13 C in HC0 3 - and lower nutrients. On the other hand, deep waters are

lower in <5 13 C and higher in nutrients because of the decomposition of organic matter. Accordingly the distribution of 12C is similar to that of the nutrients. Therefore primary productivity is thought to be high when the supply of the nutrient and dissolved HCO; with low <5 13 C is high. Consequently, in this case it would be expected that a negative correlation would occur between both records of <5 13 C and SIRM. In addition, we concluded before that most of the SIRM variations whose maximum to minimum ratio range is up to 8 are caused by the variation in intensity of the CaC0 3 dissolution. Thus, the influence of the variations in primary productivity, whose maximum to minimum ratio range is less than about 2 (Mix, 1989: Herguera and Berger, 1991), on the content of bacterial magnetite is not great at these sampling sites. Recent geochemical studies (Boyle and Keigwin, 1986; Boyle, 1988 , 1990; Curry, 1988; Duplessy et aI., 1988) have shown that changes in nutrient distributions have taken place during the glacialinterglacial cycles that have occurred in the earth's recent history; nutrient concentrations used to be higher in the deeper waters (> 2500 m) of the glacial North Atlantic than they are today, whereas nutrient concentrations were lower in the upper waters (1000-2500 m) of the glacial North Atlantic and possibly in all of the major ocean basins. Very little is known about how <5 13C in the surface waters of the Pacific changed during the cycles. However, it is likely that <5 13 C values in the surface waters are higher when nutrients are more highly concentrated in the deep waters, if the model showing that nutrients and carbon with low <5 13 C are transferred from intermediate into deep waters is taken into account. The above mentioned nutrient concentration changes in the surface Pacific can also be predicted using a box model of the atmosphere and ocean (Keir, 1988). There is no direct evidence which shows that the variations of <5 13 C in the planktonic foraminifera in the western equatorial Pacific are determined by the ocean circulation. However, on the basis of the results presented here, the alternative changes in the vertical carbon distribution with isotopic fluctuation, brought about by the change of the ocean-circulation pattern, would be a most

T Sato et al.jPalaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215

plausible cause for the clear correlation between SIRM and c5 13 C in planktonic foraminifera. It can be concluded that the correlation shows the existence of a close connection between the surface waters and deep waters in the western equatorial Pacific Ocean and that the correlation probably occurred through carbon with isotopic fractionation, and nutrient transfers during the glacialinterglacial cycles between intermediate and deep waters. The radiocarbon age structure of the core top sediment was examined in order to find out the effects of bioturbation on deep-sea sediment records. The thickness of the mixed layer, in which a 14C age is constant with depth, ranges from 8 to 14 cm for the equatorial Pacific Ocean at a depth of about 4000 m (Broecker et aI., 1991). It was suggested that much of the CaC0 3 dissolution occurs only within the uppermost centimeter of the sediment in the mixed layer (Archer et aI.,

Appendix 1 SIRM in KH 73-4-7 Depth SIRM Depth (x 10.3 (em) (em) 138 1.31 144 1.32 167 155 143 l.08 108 1.07 106 1.06 113 1.22 1.22 098 106 1.51 180 2.50 223 242 236

(x 10-3

Depth (em)

cmu/gl

emu/gl 09 23 36 50 64 7.7 91 104 11.8 132 145 15.9 173 186 200 21.3 22.7 241 254 26.8 28.1 295 30.9

SIRM

322 336 350 363 37.7 390 404 418 43.1 445 459 472 48.6 49.9 51.3 527 54.0 554 568 58 I 59.5 60.8 622

221 227 259 253 267 278 2.55 219 161 143 133 121 126 1.36 140 151 147 148 I 18 122 123 147 1.77

SIRM (x 10-3

1990) and also that there was evidence of chemical erosion (Broecker et aI., 1991). A difference in the influence of bioturbation would be expected between SIRM and c5 13 C records. However matching of the records implies that apparent differences in the effects of bioturbation are less marked than expected between the dissolution record represented by the SIRM intensity variation and the c5 13 C record. The data we have obtained so far appears insufficient to prove this, and further study is needed.

Acknowledgments We wish to thank Prof. T. Oba, Dr. H. Fukuhara, Prof. I. Koizumi, Prof. S. Nishida and Prof. T. Hashimoto for their valuable discussions. T. Sato wishes to acknowledge the Sumitomo Foundation.

Depth (em)

227 2.21 306 325 284 286 255 2.02 2.12 2.34 230 158 130 1.29 119 124 130 162 304 290 358 406 395

SIRM (x 10-3

Depth (em)

emu/g}

emu/gl 636 649 663 676 690 704 717 73 I 745 758 772 785 79.9 813 826 840 849 86.7 88 I 894 908 922 935

205

94.9 962 97,6 99.0 1003 1017 103 I 104.4 1058 107 I 108.5 1099 111.2 1126 114.0 1153 1167 1180 1194 1208 122 I 1235 1248

386 323 313 323 316 353 299 294 381 357 519 547 519 4.54 543 475 268 1.83 201 227 2.50 338 376

SIRM (x 10-3

Depth (em)

emu/a)

emu/al 1262 127.6 128.9 \30.3 1317 \33.0 1344 1357 137 I 1385 1398 1412 142.6 1444 1453 1466 1480 1494 1507 152 I 1535 1548 156.2

398 4.11 368 365 405 3.62 242 196 1.81 181 158 1.89 204

213 161 2.06 230 282 2.81 3.00 2.65 283 260

SIRM (x 10-3

157.5 158.9 1603 1616 1630 164.3 1657 167 I 1684 1698 171.2

172 5 1739 175.2 1766 178.0 1793 1807 182,1 1834 184.8 186 I 187.5

1.99 263 2 II 203 2.03 204 2.23 242 239 205 1.84 169 179 1.56 1.47 133 122 107 090 099 108 106 I 17

T. Sato et al./Palaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215

206

Appendix 1 (continued)

Depth

SIRM

Depth

SIRM

Depth

SIRM

Depth

(em)

(xlO-J

(em)

(xI0-3

(em)

(xlo-3

(em)

emu/g) 1889 1.28 190.2 1.51 191.6 195 1929 164 1943206 1957 2.21 1970 2.39 198.4 326 1998 374 201.1 3.18 2025 2.64 2038 190 205.2 1.42 2066 140 2079 131 2093 1.37 2107 1.61 2120 171 2134 1.90 2147 161 2161 146 2175 1.50 2188 124 2202 136 221.6 1.11 2229 121 2243 131 225.6 1.16 2270 142 2284 152 2293 181 231 I 1.82 2324 217 2338 2.73 2352 280 2365 283 2379 313 2397 346 2406 353 2420 417 2433 327 2447 300 246.1 412 247.4 447 24gg 498 2502 4.40 2515 399 2529 415 2542 302

cmu/g) 256.1 2579 2588 2597 2610 2620 263.8 265 I 266 5 2679 269.2 270.6 2719 2733 2747 276.0 277.4 2788 280 I 2815 282.8 2842 2856 2869 288.3 2897 291.0 2924 2937 295 I 2965 2978 299.2 300 5 3018 303 I 304.3 3056 3068 3081 309.3 3106 3118 313 I 314.3 3156 316.8 318 I 3193

4.03 626 439 533 602 556 509 4 12 3.12 3.51 309 3.15 331 309 3.28 322 3.43 3.08 329 282 253 194 2.52 2 II 195 1.97 I 82 215 2.00

189 196 180 192 199 289 1.49 149 1.66 149 190 2 14 200 271 280 3 14 325 3 19 338 439

emu/g) 320.6 4.07 321.8 382 323 I 3.82 324.3 321 3256 349 326.8 376 328.1 384 3293 4.23 3306 4.13 331.8 422 333 I 359 334.3 4.01 335.6 387 3368 3.28 338 I 330 3393 3.09 3406 331 341.8 3.31 343.1 252 3443284 3456 252 346.8 264 348.1 264 3497 255 3506 235 351.8 257 353.1 252 354.3 265 3560 299 3568 284 358 I 245 3593 335 3605 3 II 361.8 286 363.0 295 364 3 303 365.5 270 366 8 213 3680 I 91 3693 201 3710 156 3722 1.50 3735 1.37 3747 163 3760 I 43 377 2 1.65 3785 I 80 3797 1.95 3810 082

SIRM (x I0-3 emu/g)

3822 1.63 383.5 230 384.7 308 3860 283 3872 3.72 3884 271 3897 279 3909 318 392.2 3.87 3934 328 3947 248 3959 299 397.2 299 3984 296 3997 3.63 400.9 386 4022 5.02 403.4 297 4047 169 4059 198 4072 227 4084 260 4097200 4109 2.94 4126 267 4139246 4151234 416.3 2.40 4176 204 4188 I 93 420 I I 70 4213 168 4226 161 4238 146 425 I I 43 426.3 138 4276 150 4288 150 430 I 154 4313 1.76 4326 2 10 4338 I 21 4347 163 4355 1.91 4368 227 4384 240 4397 262 4409 289 4422 292

Depth

SIRM

Depth

SIRM

(em)

(xlo-3

(em)

(x I o-J

486.6 4874 4883 489.2 490 0 490 9 491 8 4926 4935 4943 4952 496 I 4969 4978 4987 4995 500.4 501 3 502 I 5030 5038 504 7 5056 506.4 5073 508.2 5090 509 9 5107 511 6 5125 5133 5142 515 I 5159 516.8 5177 5185 5194 5202 521 I 5220 5228 5237 5246 5254 5263 527 I 528 ()

492 532 554 537 541 541 5.48 5.37 640 403 4.01 5.04 5 II 479 379 351 3.54 368 423 453 400 406 353 387 419 379 391 371

emu/g)

emu/g) 4439 395 4447499 445.6 482 4465 435 447.3 468 448.6 473 4495 396 4503 488 4512 544 452 I 5 II 4529 325 4538 331 4547 3 14 455:; 286 4564 232 4572 2.31 458 I 204 4590 214 4598 208 4607 218 461 6 204 4624 171 4633 220 464 I 232 4650 199 465.9 203 466.7 1.99 4676 184 4685 193 4693 2.07 470.2 228 4710 206 471 9 203 472.8 2.30 4736 235 4745 294 4754 293 4762 296 477 I 282 478.0 3 10 4788 304 4797 293 4805 306 4814 3 ()() 4823 3 II 483 I 393 4840 450 4849 426 4857 487

396

333 350 3.40 361 319 299 292 306 219 220 219 239 232 227 2.20 2116 300 293 3 12 3.31

T Sato et al.jPalaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215

207

Appendix 1 (continued) Depth

SIRM

Depth

SIRM

Depth

(em)

(xI0-3

(em)

(x 10-3

(em)

5289 5297 530.6 53l.5 5323 5332 5340 534.9 5358 537 I 5379 5388 5397 5405 5414 5422 543 I 544.0 5448 5457 5466 5474 548.3 5492 5500 5509 551.7 5526 5535 5543 5552 556 I 5569 557.8 5586 5595 5604 5612 562.1 5630 5638 564 7 5655 5664 5673 568 I 5690 569.9 5707

289 343 361 357 373 363 366 301 322 400 369 338 358 3 18 300 234 229 243 2.20 221 219 238 2.35 228 253 2.73 254 229 255 356 304 443 443 411 4.20 468 446 4.29 399 3.91 3.80 393 390 4.22 417 356 399 4.46 4.29

emu/g)

emu/g)

5716 459 572 5 4 19 5733 294 574.2 274 5750 313 5759 3 18 5768 299 5776 271 5785 2.72 5794 307 580.2 2.89 581 I 300 5819 286 582.8 308 5837 287 5845 272 5854 288 5863 2.94 587.1 288 5880 363 588.8 373 5897 3.90 5906 389 5914 379 5923 353 5932 313 5940 270 5949 2.85 5958 361 596 6 357 5975 356 598.3 2.91 599.2 263 600 I 259 6009300 6018 2.83 602.7 293 603.5 334 604.4 371 6052 479 606.1 4.38 6070 329 6078 423 6087 4.83 609.6 4.55 6104 441 6113 476 612.2 4.62 6130 453

SIRM (xI0-3 emu/g)

6139 6147 6156 6165 6173 6182 619 I 6199 6208 6216 622.5 6234 6242 625 I 6260 626.8 6277 628.5 6294 6303 631 I 6324 633.3 6342 635 I 6360 6368 6377 6386 6395 6404 6412 642 I 6430 643.9 6448 6457 6465 6474 6483 6492 650 I 6509 651 8 6527 6536 6545 6553 6562

477 439 411 419 465 4.52 393 389 3.69 327 430 422 360 356 4.00 4 18 399 401 437 455 4.63 479 4.66 453 4.44 464 494 473 379 3.84 3.68 350 351 343 347 347 353 3.12 300 3.09 312 3.05 3 17 325 308 363 368 363 354

Depth

SIRM

Depth

SIRM

Depth

SIRM

(em)

(x 10-3

(em)

(xlO-J

(em)

('(10-3

emu/g)

657 I 3.47 6580 3.78 6589 4 14 6597 458 660.6 442 6615 449 662.4 416 6633 413 6642 4.25 665.0 421 665') 431 6668409 667.7 3.63 6686 357 6694 334 6703 3 10 6712357 6721 371 6730 373 6738 386 674.7 3.89 675.6 4.32 6765 418 677 4 405 6787 405 6796 4 II 680.4 406 6813 4.10 6822 432 683 I 4.21 6840 432 6849 451 6R5.7 4.11 6866 442 687.5 462 6R8.4 406 6893 4.24 690.1 421 6910 392 6919 393 6928 356 6937 337 6945 353 695.4 3.62 696 3 376 6972 388 698 I 349 6989 320 7003 3 10

emu/g)

7012 7020 7029 7038 7047 7056 7064 7073 7082 709 I 710.0 7108 7122 713 () 7139 7148 7157 716 (, 717.4 7183 7192 720.1 7210 7219 7227 7236 724.5 7254 7263 727 I 728.0 7289 7291\ 7307 7315 732.4 7333 7342 735 I 7359 7368 7377 73R6 7395 7404 741.2 742 1 7430 7439

318 288 235 215 206 207 224 160 146 146 149 157 215 1 81 161 138 1.39 151 145 203 213 197 2.17 2 III 2.17 2.21 2.42 250 266 253 233 221 215 2.14 210 I 99 2.04 1.90 I !IS 203 193 I 80 171 I 67 161 154 1 53 146 155

emu/g)

7448 7456 7465 7474 7483 7492 7500 7509 75111 753 I 7540 7549 7558 7566 7575 7.5114 7593 760.2 761.1 7619 762.8 7637 7646 7655 7663 7672 768 I 7690 7699 7707 7716 772 5 7734 774.7 7756 7765 777 3 7782 779 I 7800 780.9 7818 7826 7835 7844 7853 7862 7870 787.9

142 132 131 I 44 I 30 1.28 136 1 33 136 I 53 1.57 162 I 80 191 I 94 2 09 I 97 198 224 240 233 238 236 244 235 240 235 225 214 220 2.30

222 229 224 243 260 2.57 278 280 292 289 245 228 2.16 2.54 232 244 221 236

T. Sato et al./Palaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215

208

Appendix 1 (continued) Depth

SIRM

Depth

SIRM

Depth

(em)

(xlO-J

(em)

(xlO- J

(em)

emu/g)

7888 7897 7906 7914 792 3 7932 794 I 7950 7958 796 7 7976 798.5 7994 8003 801.1 8020 8029 8038 804.7 11055 8064 8073 808.2 809 I 8099 8108 8117 8126 8135 8143 815.2 8161 8170 817.9 8188 819.6 8205 8214 8223 8232 8240 8249 8258 8267 8276 8284 8293 8302 831 I

3.11 287 2.95 314 374 420 378 375 507 500 392 3.75 390 3 17 252 228 253 2.41 258 301 265 330 344 369 375 381 4.01 4 12 371 397 434 399 351 342 2.99 313 327 269 3 ()() 285 338 296 276 292 253 2.72 300 263 274

emu/g)

831 9 237 8328 3,03 8337 3 15 8346 286 835.4 290 8363 278 8372 274 1138 I 276 838.9 271 8398 258 8407 267 841.6 265 8424 260 8433 231 8442 2.24 845 I 220 845.9 2.15 8468217 848 I 204 8490 229 8499 251 8508 I 83 8516 189 8525 197 8534 193 8543 172 855 I I 55 856 0 1.68 8569 135 8578 I 53 8586 154 8599 161 8608 \.73 8617 170 862 (, 165 8634 203 864.3 200 8652 2.24 866 I 228 8670251 8678 2.67 8687 267 869.6 272 8705 265 871 3 272 872 2 286 873 1 271 8744 281 8753 2 16

SIRM (x 10-3 emu/g)

876 I 233 877 0 249 877 9 262 8788 270 8796 240 8805 242 881.4 247 8823 2.19 883 I 243 8840 240 884.9 2.25 8858 241 8866 291 8875 289 8884 293 889.3 357 890 I 348 8910 342 891.9 392 8928 366 8936 297 8945 356 8954 331 896 7 339 8976 336 8985 419 899.3 353 9()()2346 901 I 380 9020 346 9028 362 9037 3 S5 9046 384 9055 374 906.3 369 9072 371 908.1 341 909.0 335 9098 310 9107 284 91/ 6 279 912.5 280 9133 276 9142 272 9151 260 9160 249 916 K 232 9182 215 9190209

Depth (em)

SIRM (x 10. 3 emu/g)

9199 2.40 920.8 2 II 9217 171 9225 1.62 9234 153 9243 1 67 168 925.2 926.0 165 9269 161 9278 166 9287 1 74 9295 155 9304 140 9313 146 9322 165 9330 I 48 9339 1.43 9348 138 9357 146 9365 149 9374 I 50 9383 1.51 9392 148 9400 I 55 940.9 1.60 9418154 <)427 162 9440194 944 9 185 94S 7 2 15 9466 233 9475 255 9484 242 9492 262 950 I 297 951 0 279 9519 2.86 9527 296 9536 308 9545 261 9554 233 9562 204 957 1 I 99 9580 221 9589 240 9597 270 960 (, 254 9615268 9624 27()

Depth

SIRM

Depth

SIRM

(em)

(x 10.3

(em)

('(10- 3

emu/g)

emu/g)

963.2 239 964 I 256 9650 247 966.3 249 9672241 9680 250 9689 259 969.8 269 9707 244 971 5 281 972.4 2.60 9733 222 9742 267 9750 223 9759 I 82 976.8 144 977 7 138 9785 141 9794 1.29 9803 130 9812 159 982 I I 33 9829 I 33 9838 150 9847 I 47 9856 I 41 9864 128 9873 I 48 9882 I 51 989 I 149 9!199 145 990 !I 158 991 7 168 9926 I 74 993 <) 164 9947 189 9956 176 9965 I 75 9974 179 9982 2 17 999 I 2 II 10000 229 10009214 10017 251 10026 254 1003 5 247 10044 252 10052 275 10061 261

10070 10079 10087 10096 10105 1011 4 10122 1013 I 10140 10149 10157 10166 1017.5 1018!1 10197 10206

259 260 237 228 242 234 208 I 76 181 I SO 213 161 174 I 80 171 191

T Sato et ai/Palaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215 Appendix 2 Isotopic data in KH 73-4-7 Depth

<') 180

<')I.le

- - -18- - - Depth

<')

0

<')l3e

Depth

<') 180

Depth

(em)

(0/00)

(%0)

(em)

(%0)

(%0)

(em)

(0/00)

(em)

09 23 6.4 77 104 II 8 154

III 2

-039 -0.14 -005 -0 14 0.03 -0.38 -0.19 -047 -0.69 -129 -032 -054 -008 -0 I -047 -058 0 18 -031 -0.47 -028 -0.04 009 -004 -0.7 -036 -06 -0.34 -019 -026 -006 -035 -031 -001 -053 -007 002 0.07 017 0.01 01 -0 15 -024 007 -059 045 -02 -058

114 1153

-008

I 76 1.49 2.12 1.73 2 I 67 1.47 177 I 18 129 1.75 1.83 I 77 I 66 165 I 57 I 36 III 08 I 76 1.52 133 I 48 I 28 135 148 I 43 158 128 I 98 I 25 I 62 I 89 159 I2 124 149 14 1.24 I 39 0.96 15 168 I 33 196 I 94 I 53 212 1.79

118 -026 119.4 0.08 122.1 01& 1303 -046 134.4 -061 135.7 -093 137 I -075 1385 -059 1398 -049 141 2 -0 58 142.6 -048 143 5 -066 1444 -026 1453 -027 1466 -047 1494 -081 1507 -0.64 152 I -068 1548 -0.84 1575 -074 1589 -094 1603 -089 161 6 -lOS 163 -073 164 3 -045 ]ti5 7 -062 167 I -059 1684 -056 169 S 023 1712 026 172; 0.33 173.9 034 1752 035 1766 032 178 019 1798 012 180.7 004 182 I -0 26 1834 02 1848 003 186 I -02 1875 -018 189 3 -0 34 1907019 192 1934 021 196 I -042 1975 -061 202 9 -0 39

144 163 1.8 176 184 155 1.49 I 69 1.72 I 63 1.71 I 55 179 099 191 163 206 165 I 99 I 74 148 124 I 56 I 68 I 74 I 36 I 56 177 165 105 I 14 1.35 I 54 134 132 123 12 I 21 15 096 09 138 I 21 115 143 162 I 54 151 I 71

In 21.3 24.1 25.4 28 I 29.5 336 36.3 39 41.8 445 48.6 49.9 527 54 554 56 II 58.1 608 63 6 64 9 663 71 7 73 I 745 758 77 2 785 799 813 826 84 849 894 908 99 1003 1044 1085

2043 -028 168 20; 2 -052 104 2066 -006 138 2079 -054 14 210 7 -029 134 212 -018 107 213.4 -069 I 18 2147 -0.6 147 2161 -0;3 163 2175 -05 128 2188 -052 143 2202 -041 14 2243 -066 118 2256 -1.06 I 13 227 -109 14 2284 -0.47 I 88 2293 -0.32 123 231 I -099 106 232.9 -003 163 2352 -04 133 2365 -0 14 171 2406 -038 235 2433 -0.12 15 246 I -033 165 251 5 -021 176 2688 -254 -061 2724 -0.41 12 276 -044 123 2788 -063 103 280 I -0 II 156 2828 001 145 002 158 286 2869 003 I I 2897 046 I 74 291 026 1.36 295 I 004 138 2992 023 249 3005 001 131 303 I 034 121 3056 0 14 I 27 3068 0 19 I 53 308 I 0 15 I 38 309 3 -0 04 I 06 3106 009 114 3118 003 14 3143 004 148 3168017 176 318 I -0 08 I 83 3193 -13 053

321 R 324.3 3293 331 8 3343 3368 3393 343 I 3456 3497 351.8 3543 361 R 3635 3655 368 3693 371 372.2 3747 377 2 3797 3822 3847 3872 3897 392 2 3972 3997 4009 4034 4084 4122 4126 415 I 4163 4188 421 3 423.8 4276 430 I 4326 434 3 435 I 4388 443 446 5 4486 4792

209

<') 180

(0/00)

-025 -03 -025 -021 -007 048 -0 15 0 17 -0.06 017 009 028 -OJ I

-023 -027 -0 19 -0.21 -003 -001 -0 15 -0.01 -028 006 -024 -033 -019 -025 -0 13 -004 -041 -054 -047 -0 16 -0.31 -0.21 -012 -025 -083 -051 -022 -0 02 -026 -0 18 -0 04 -0 15 -0 18 -0 39 -032 () 04

147 186 1<) 205 019 209 167 184 191 199 186 197 188 189 174 145 1.74 15 149 171 158 167 171 184 179 163 177 194 159 153 149 137 I 86 17 153 181 169 I 07 I 02 L06 I II I 81 I 13 I 43 1 61 I 59 I 72 I7 162

T Sato et al./Palaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215

210

Appendix 2 (continued) Depth 1)\80

I)\3C

Depth 1)\80

I)UC

Depth 1)\80

I)\3C

Depth 1)\80

I)UC

(0/... )

(0/00)

(em)

('!(,.)

(%0)

(em)

(0/0 0 )

(%0)

(em)

(%0)

(%0)

I 81 U3 I 57 15 166 I 89

625 I -0 43 6399 -052 649 6 -0 59 662 -0.43 704 2 -0 75 706 -039

I 62

802 9 -0 46 825 8 -0.32 1145 I -0 03 1145 5 -027 873 5 -051 905 -039

I 63 197

9234 -0 58 944 9 -0 06 958.4 -0 83 10057 -052 10188-038

(em)

492 6 5289 553 5 577.6 6009 610.4

-0 15 -027 -042 -022 -03 -08')

I 76 2 04 I 116 2 29 165

I 72 J 112 I 75 I K8

I 82

I 79 I 71 186 184

Appendix 3 CaC0 3 contents in KH 73-4-7

------

Depth

CaC03

Depth

CaC03

Depth

CaC03

Depth

CaC03

(em)

(%)

(em)

(%)

(em)

(%)

(em)

(%)

45 154 209 31 8 400 400 4KJ 604

764 745 77 5 65 6 597 676 67.7 51 3

65 8 72 {, 749 86 3 91 3 98.5 102(, 1103

51 3 629 626 62 6 370 50 I 488 35 3

127 I J3\ 2 1380 1525 1798 2034 2247 2252

284 434 71 3 610 732 68 I 75 I 72 8

2370 614 2529 493 2838 (,08 3197 508 376.8 710 4452 51 7 4603667

Appendix 4 SIRM in KH 73-4-8"--_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Depth SIRM Depth SIRM Depth SIRM Depth SIRM Depth SIRM Depth SIRM (em)

(xIO-~

(em)

2R

39 50 61 72 83 94 105 116

12.7 138 149 160 182 193 204 21 5 226

184 I 73 184 168 174 215 2R4 260 297 301 343 376

373

237

330 325 254 250 247 246 254 270

248

266

(em)

259 270 28 I 292 303 314 32'5

336 358 369 380 39 I 402 413 424 435 446 45 K 469 480 49 I 502

2 10 I 87 167 159 148 170 I 63 I 68 I 97 209 249 257 267 3.20 333 342 577 344 488 451 477 4.78

(x 10-.1

(em)

emu/g)

emu/g)

emu/g)

06 17

(xlO-J

51 3 524 535 546 557 568 579 590 60 I 61 2 634 645 656 667 678 689 700 71 I 72 2 733 744 755

4 10 381 333 331 361 277 258 232 255 242 233 235 236 2.50 238 242 259 263 257 293 3 19 301

(xIO-J

(em)

emu/g)

766 77 7 788 799 810 82 I 832 84.3 86.n 86:; 87.6 887 89.8 910 92 I 932 94.3 954 965 976 987 998

289 329 3 19 253 267 237 237 253 255 263 254 227 240 212 2 IX 2 14 2 J3 242 210 204 185 193

(x I 0-.1 emu/g)

1009 102.0 103 I 1042 1053 1064 1075 1086 1097 110.8 1119 1130 1135 1144 1153 117.1 1180 1189 1198 1207 1216 1225

191 180 202 160 165 1.69 17X 177 183 194 2.01 193 1 89 214 474 593 316 403 293 3 (,l) 434 428

(em)

(x )()-.1 emu/g)

1234 458 1243 454 1252 449 126 I 461 1270 4 II 1279 479 1288 450 1297 455 131 5 357 132.4 4.09 1334 3lI7 344 1343 1352 373 1361380 137 () 370 1379 402 1388 370 1397 375 1406 377 1415 392 1424 351 1433 352

T. Sato et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 113 ( 1995) 199-215

211

Appendix 4 (continued)

Depth

SIRM

Depth

SIRM

Depth

SIRM

Depth

SIRM

Depth

SIRM

Depth

(em)

(x 10-3

(em)

(x 10-3

(em)

("'(10-3

(em)

(x 10-3

(em)

(xlo-·~

(em)

emu/g)

emu/g) 1442 145 I 1460 146.9 1478 148.7 1496 1505 1514 152.3 1532 1542 155.1 1560 1569 1578 1587 1596 160; 1614 162.3 163.2 1641 1650 1659 166.8 1677 1686 1695 170.4 1713 172.2 173 I 1740 175.0 1759 1768 177.7 1786 1795 1804 181.3 1822 184.0 184.9 185.8 1867 187.6

361 335 360 399 418 422 4.02 410 371 3.75 368 355 328 3.19 294 2.87 297 2.80 2.94 3.21 316 3.15 307 316 3 12 3.06 301 309 290 2.97 297

284 313 3.30 335 366 367 379 3.97 410 4.0!! 4.55 4.24 497 4.44 4.65 479 522

1885 189.4 1903 1912 192 I 193.0 193.9 1949 1958 196.1 1976 198.5 1994 2003 201.2 202 I 2030 203.9 2048 2057 2066 2075 2084 2093 2102 211 I 2120 2129 213 8 2147 2157 2166 217.5 2184 2193 2202 221 I 222 0 2229 2238 2247 225.6 2265 228.3 2292 230 I 2310 2319

456 4.81 4.86 5.03 477 4.06 352 330 370 3.49 335 330 3.13 2.89

292 279 263 2.70 286 2.81 2.75 281 277 2.76 253 228 22!! 224 217 241 240 2.46 252 265 2.!!!! 294 301 3.03 290 2.92 291 301 295 3.11

UO 3.03 284 2.67

emu/g) 232.8 2337 2346 235.6 236.5 2374 2383 239.2 240.1 2410 2419 2428 243.7 2446 2455 246.4 247.3 248.2 249.1 250.0 250.9 2518 2527 253.6 254.5 2554 2564 2573 25!! 2 259.1 2600 2609 261 !! 2627 2636 2645 2654 2663 2672 268.1 2690 2699 2708 272 6 2735 2744 275.3 276.2

3 15 385 597 6.63 6.03 565 519 5.16 4.40 585 504 5.70 570 521 423 337 331 "327 3.42 3.30 308 3 15 305 297 288 2.80 225 297 270 254 193 150 150 143 1.47 154 I 78 185 164 158 186 195 190 200 217 2.01 185 1.85

emu/g)

emu/g) 277 2 278 I 2790 2799 280.8 281.7 2826 283.5 2844 2853 286.2 287.1 2880 288.9 289.8 290.7 2916 292.5 2934 2943 2952 2961 297 I 2980 2989 2998 3007 3016 302.5 3034 3043 3052 3061 3070 3074 308.3 3092 310 I 3\1 0 3\1 9 312.8 313 7 314.6 315.5 3173 318.2 3191 3199

176 1.81 189 186 184 188 1.89 1.95 185 196 2.06 209 216 220 236 203 190 I !!6 194 1.98 207 2.17 2.24 216 218 2.09 202 204 204 209 211 23!! 2.39 261 265 255 256 2.23 210 183 160 164 175 186 161 1.68 156 159

320.8 321 7 322.6 323 5 324.4 3253 326.2 327 I 3280 3298 3307 3315 332.4 3333 3342 335 I 3360 3369 337.8 3387 339.6 3405 3414 3423 343.2 344.0 3449 3458 346.7 3476 348.5 349.4 3503 351.2 352.1 3530 3539 3548 3556 356.5 3574 3583 3592 360 I 361.0 3619 3628 3637

179 1.86 1.92 191 1.94 1.84 I 88 I !!9 188 164 \ 59 140 1.50 144 1.50 130 1.37 \ 35 140 141 1.51 149 1.52 147 \ 39 163 204 2.16 189 202 189 1.76 165 156 153 1.48 1.55 169 17S

1.7\ 169 172 I 76 172 175 169 1.64 154

SIRM (x 10-3

emu/g) 364.6 3655 3664 367.3 368.1 3690 3699 3708 371.7 3726 3735 374.4 3753 3762 377 I 378.0 3789 3797 380.6 381.5 3824 3833 3842 385 \ 3860 386.9 387R 388.7 389.6 3905 391.4 392 2 393 I 3940 3949 395 H 396 7 3976 3985 3994 4003 402 I 4030 4038 4047 405.6 406.5 4074

\ 56 156 148 153 146 143 14; 1.45 1.38 122 123 133 149 132 123 107 103 \ 00 099 0.87 0.99 0.90 074 0.!!4 0.90 086 0.87 0.88 0.94 0.9\ 091 089 092 095 103 099 089 095 1.04 107 106 I 19 126 132 141 140 144

1.37

T Sato et al.j Palaeogeography, Palaeoclimatology, Palaeoecology 113 ( 1995) 199-215

212

Appendix 4 (continued) Depth

SIRM

Depth

SIRM

Depth

(em)

(x IO-·~

(em)

(x 10-3

(em)

emu/g)

emu/g)

4083 148 4092 148 410 I 153 4110 158 4119 156 4128 159 4137 I 32 4146 130 4155 132 4163 I ~8 4172 129 418 I 1.41 4190 142 4208 I 55 4217 151 422 6 155 4235 I 58 4244 167 4253 I 76 4262 195 427 I 204 427 I) 243 428.8 258 4297 251 4306 234 431 :; I 82 4324 225 4333 222 4342 231 435 1 I 93 43602.16 4369 243 4378 200 438.7 I 62 4396 158 4404 138 441 3 132 4422 126 443 I 129 444 0 I 15 4449 112 4458 093 4467 090 4476 094 4485 090 4494 098 450:1 108 4512 104

4520 4529 4538 4547 4556 4565 4583 4592 460 I 46LO 4619 4628 464 5 465.4 4663 4672 468 I 4690 4699 4708 471 7 472 6 4735 4744 4753

477 0 477 '.I 4788 4797 4806 4815 4824 4833 4842 4115 I 41160 4869 4!!86 4895 4904 4913 492 2 493 I 4940 4944 4953 4970 4983

10(, 101 103 Ll4 I 16 121 134 132 145 145 /55 167 163

1.56 154 160 142 120

I 1,8 /01 /02 I 15 III 109 096 0.85 088 097 094 098 099 102 103 098 096 I 10 097 094 109

I/O I 18 I 15 137 / 19 240 229 220

273

S/RM ('\10-3

Depth (em)

emu/g)

4996 5009 5022 5048 506 I 5074 50!! 7 510.0 5113 512.6 5139 5152 5165 5178 519 I 5204 52/ 7 523 0 5243 5256 5269 528.2 5295 5308 532 I

5334 5342 535 I) 5368 53!! 5 5398 541 I 5424 5437 5450 5463 5476 5489 5502 55 15 5528 554 I 5554 5567 5580 5593 5606 5619

26R 237 290 249 304 332 414 483 42()

4.86 584 594 575 617 569 6J3 577 539 371 439 425 368 375 365 404 419 375 472 401 HI 332 274 369 350 358

H9 4.02 401 4\1

347 361 325 29() 259 299 252

270

265

SIRM (x/0- 3

Depth (em)

293 296 289 343 246 225 194 168 186 16/ 189 /69 I 71 222 237 274 231 249 295 352 369 3/0 350

346 381 439 436 3&7 29(} 302 332 3 10 3 10 262 335 228 244 223 283 201 2&3 268 399 203 234

203 209 164

Depth (em)

emu/g)

emu/g)

5632 5645 565 R 567 I 5684 5697 5710 572 3 5736 574,9 5762 577.5 578 II 580 I SRI4 5826 583 <) 5852 586.5 587.8 589 I 5904 591 7 5930 5943 5956 596 9 5982 5995 6008 602 I 603.4 6047 6060 607.3 608 (, 6099 6112 6125 6138 615 I 6164 6177 6190 6203 6216 6229 6242

SIRM ('\ IO-·~

625.0 626,8 628 I 6294 6306 6319 6332 6345 6358 6367 6384 6397 6410 6423 6436 6449 6462 6475 648.8 650 I 6514 6527 6553 6566 6579 6592

290 247 209 3 19 276 235 341 252 2 12 259 2,29 241 207 2 12 158 159 158

660.5

288

6618 6639 6652 6665 667l! 669 I 6704 6735 674l! 6761 677 4 6786 6799 6812 682.5 6838 6115/ 6!!64 6873 68!! 2 689 I

3 10 3 14

I 56 146 149 148 164 179 /1<9 186 249

221 301 191 223 346 19& 214 239 251 249 202 179 159 164 I 51 220 2, J3

204 227

69() 4 691 3 692.2 693 I 6940 694 g 6957 696 6 6975 6984 6993 700 I 7010 701 9 702 \\ 7037 7046 70S 4 7063 7072 7090 7099 7107 7116 7125 7\3 4 714:1 7152 7160 7169 7183 719 I

SIRM (\10-" emu/g) 197 243 267 261 269 262 290 303 3 32 3 II 557 353 349 361 303 I 611 234 246 231 171 1.69 2 \I I 83 1.44 / 79 I 70

7209 7218 7227 7236 7244 7262 727 I 7280 7289

I 77 I 71 I 73 176 19K 203 2m 240 251 27l! 304 319 2,63 252 242 240

7302 73/ I

223 220

7319 7328

186 192 I 91 I 71

7200

7337 7346

T. Sato et al./Palaeogeography, Palaeoclimatology, Palaeoecology 113 (1995) 199-215

213

Appendix 4 (continued) Depth

SIRtvI

Depth

(em)

(x 10- 1

(em)

Depth

SIRM

Depth

SIRM

Depth

SIRM

Deplh

(em)

(x 10-3

(em)

(x 11)-3

(cm)

(x J()-.l

(em)

emu/g)

cmu/g)

735.5 182 736.4 176 7372 1.90 738 I 1.<)1 739.0 210 7399 2.34 740.8 253 7417 247 742.6 2.50 743.4 2.87 7443 279 744 g 2.52 745.6 2.28 7465 206 7474 2.12 1.92 749.2 750.1 195 750.9 2.31 751.8 2.63 7527 271 295 753.6 754.5 3.74 755.4 4.05 757 I 372 758.0 2.86 334 758.9 7598 275 7607 2.79 2.61 761.5 762.4 2.79 7633 3.16 764.2 301 372 765.! 766.0 330 7669 3.65 7677361 768.6 3.84 769.5 3.41 770.4 3.69 771.3 3.19 772.2 356 7730 303 774.8 5.37 509 7757 776.6 4.59 7775 6.07 779.2 4.66 780 I 4.96

SIRM (,,10-.1

. 78l.0 781.9 7828 783.6 784.5 7863 7872 788.1 7889 789.8 790.7 791.6 792.5 793.4 794.2 795.1 7960 797.8 798.7 799.5 800.4 801.3 8022 803.! 804.8 80S 7 806.6 80H S088 S09.7 8106 811.5 812.4 813.2 S14.1 S15.0 815.9 816.8 8177 818.5 820.8 8216 8252 826.9 8287 829.6 8305 831.4

5.31 451 481 4.32 4.25 4.83 4.72 4.92 479 638 5.7; 5.51 437 4.31 4.66 4.35 356 4.09 292 3.65 2.54 2.46 273 2.60 318 272 298 2.S4 3.21 3.13 297 2.74 312 2.35 249 2.92 2.67 293 321 2.83 2.93 319 263 286 178 201 213 259

cmu/g)

cmu/g)

832.2 833.1 8340 8349 8358 836.7 837.5 838.4 839.3 8402 841.1 842.0 842.S 8437 8446 8455 846.4 847.3 848.1 849() 849.9 8S0.8 851.7 852.6 853.4 854.3 855 2 856.1 8S7.0 8579 S587 859.6 860.5 8614 8618 862.7 863.6 864 5 865.4 866.3 8671 868.0 868.9 869.8 8707 871.6 873.4 874.3

2.38 2.17 2.43 3.01 3.05 3.24 3.54 3.47 393 3.79 3.75 3.79 3.64 3.75 3.75 3.57 3.64 3.69 3.03 348 327 309 3.58 4.00 4.45 421 4.30 5.55 397 4.24 3.96 3.91 3.93 3.94 3.43 4.27 4.69 5.34 5.92 5.65 6.93 557 6.66 612 4.03 366 4.69 4.30

876.1 V,770 877.9 878.8 879.7 880.6 881.5 882.4 883.3 886.0 V,86.9 890.5 891.4 892.3 893.2 894.1 895.0 895.9 896.8 900.4 901.3 902.2 903.1 9040 904.9 905.8 906.7 907.6 9085 909.4 910.3 911.2 915.7 916.6 918.4 919.3 9202 921.1 922.0 9229 9238 924.7 925.6 9265 9274 928.3 929.2 930.1

3.56 3.52 3.34 2.88 2.25 181 272 304 2.93 3.81 2.98 2.13 2.20 2.34 2.26 2.31 218 2.\3 2.38 2.01 2.00 1.97 2.21 2.16 2.22 2.43 2.36 2.87 3.45 3.38 3.08 2.90 332 3.68 3.07 3.36 230 2.04 2.23 2.48 2.36 200 1.94 \ 9\ 2.04 2.\3 2.05 2.22

emu/g)

9310209 931.9 2.03 932.8 2.10 933.7 2.17 934.6 2.83 935.5 2.74 9364 267 9373 2.62 938.2 2.48 939.1 2.46 940.0 I 76 940.9 2.17 941.8 2.58 942.7 2.62 943.6 2.50 246 944.5 945.4 2.30 946.3 2.30 947.2 2.35 948.\ 2.49 949.0 2.69 949.9 2.90 288 950.8 951 7 3.11 952.6 2.90 3.06 953.5 954.4 3.19 9553 320 956.2 3.\3 957.\ 3.\9 958.0 3.12 958.9 3 10 959.8 ;;.19 960.7 3.14 961.6 3.14 9625 283 963.4 2.77 9643 2.90 9652 2.91 966.1 2.75 967.0 2.92 967.9 2.79 2.71 968.8 969.7 2.75 970.6 2.69 971.5 2.62 972.4 2.57 973.3 2.47

SIRM (xI0-3 emu/g)

9742 2.44 975.1 2.39 976.0 2.52 976.9 2.40 977.8 2.27 978.7 l.80 1.77 979.6 980.5 1.79 9814 2.43 982.3 2.56 983.2 2.64 9841284 9850 3.02 985.9 2.99 986.8 2.49 268 987.7 988.6 2.79 989.5 2.81 9904 278 991.3 2.76 992.2 2.82 994.0 2.91 994.9 269 995.9 2.81 996.8 2.8\ 997.7 2.76 9986264 999.5 2.82 IO(}O.4 2.95 1001.3 3.25 1002.2 3.35 1003.1 3.33 1004.0 2.40 1004.9 293 1005.8 2.92 1006.7 2.99 1007.6 2.96 10085 2.93 10094 2.S9 1010.3 3.08 1011.2 2.88 1012 I 2.62 1013.0 2.92 1013.9 2.86 1014.8 2.72 1015.7 283 1016.6 27\ 1017.5 2.82

214

T. Sato et al./Palaeogeography, Palaeoclimatology, Palaeoecology 113 ( 1995) 199-215 Appendix 4 (continued) Depth (em)

SIRM (x IO-·~

Depth (em)

cmul~)

10184 10193 10202 1021 I 1022 0 1022 9 1023 8 10247

2.75 283 287 277 284 278 321 304

SIRM (-..:10- 3

Depth (em)

emul~)

10256 270 10265 278 10274 265 10283 280 10292 260 1030 I 270 10310 282 10319 277

SIRM ('1;10- 3

Depth (em)

SIRM

Depth (em)

(xIO-·~

cmul~)

emulg) 10328 10337 10346 10355 1036.4 10373 1038.2 10391

SIRM (xI0- 3

10400 10409 10418 10427 10436 10445 10454 10463

279 279 279 275 287 287 272 270

274 2.66 264 264 258 256 2.54 252

Depth (em)

emu/g) 10472 1048 I 1049.0 10499 10508 10517 1052 (, 10535

249 260 270 263 257 257 257 2.55

SIRM ('1;10- 3

emulg) 10544 10553 10562 1057 I IOS80

257 253 262 253 263

Appendix 5 Isotopic data in Kh 73-4-8 /) 180

/)ue

Depth

/) 180

/)ue

Depth

/) 180

/)ue

Depth

/) 18 0

/)He

{cm)

{%oj

{%o2

{cm)

{%oj

{%o2

{cm)

{%oj

{%o2

{cm)

{%oj

{o/oo2

495.3 500.9 506.\ 507.4 5113 515.2 516.5 519.5 525.6 530.8 535.1

-0.40 -0.34 -028 -0.34 -0.50 ·0.74 ·068 ·066 ·0.44 ·029 ·0.03

171 198 2.20 192 2.24 208 200 218 1.95 199 2.14

540.3 545.0 5502 552.8 556.7 560.6 5658 572.3 577.5 582.6 585.2

589.1 5930 5969 602.\ 6073 6185 6233 628.1 633.2 635.8 638.9

-0.58 -0.18 -0.45 ·034 ·0.17 ·0.42 ·0.35 ·0.51 ·062 ·064 ·0.65

176 1.81 1.90 2.04 163 211 2.04 2.05 217 198 167

6410 6436 648.8 654.0 6592 6648 6674 6709 6748 679.9 685.1

-0.94 159 -0.60 174 -0.54 162 ·0.51 165 ·0.38 191 ·047 179 ·057 218 ·058 2.45 ·0.37 1.78 ·083 161 ·0.92 1.12

Depth

-0.40 2.17 -0.65 2.12 -014 1.57 0.42 1.90 0.69 394 084 042 0.18 204 -0.31 159 ·0.32 1.74 ·019 1.67 ·0.29 1.67

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