- Email: [email protected]
Instability of last glacial climate from SRXFA data for bottom sediments in the Okhotsk Sea
ARTICLE IN PRESS
Nuclear Instruments and Methods in Physics Research A 543 (2005) 284–287 www.elsevier.com/locate/nima
Instability of last glacial climate from SRXFA data for bottom sediments in the Okhotsk Sea E.L. Goldberga,c,, S.A. Gorbarenkob, A.D. Shaporenkoa,c, A.A. Bosinb, V.Yh. Leskovb, E.P. Chebykina a Limnological Institute of the SB RAS, 664033 Irkutsk, Russia Pacific Oceanological Institute of the FEB RAS, 690041 Vladivostok, Russia c Budker Institute of Nuclear Physics of SB RAS, Lavrentyev prospect -11, Budker, 630090 Novosibirsk, Russia b
Available online 3 March 2005
Abstract X-ray Fluorescence Analysis with Synchrotron Radiation (SR XFA) was used to study, at a high-resolution (200 yr), the behavior of elements in an 80 kyr core record from the Okhotsk Sea. We measured biogenic Ba (BaBio), biogenic carbonate, and organic carbon as bio production indicators, elements that record the Amur terrigenous input, and Mn as signature of water ventilation and redox conditions at the sediment/water interface. The Okhotsk Sea in last glacial time responded to abrupt warm spells in the Atlantic and Greenland. Bio production in the Okhotsk Sea increased dramatically during warm D/O events and decreased during cold and dry H-events. r 2005 Elsevier B.V. All rights reserved. PACS: 07.85.Qe; 92.70.Gt; 92.40.Ni; 91.65.Rg Keywords: Synchrotron radiation; Okhotsk sea; Last glacial period; Millennial scale oscillations; Dansgaard-Oeschger and Henrich events; Biogenic barium
1. Introduction We can be now positive that the last glacial period (24–74 kyr) in Greenland was interrupted by at least 19 warm spells with a 12–15 1C Corresponding author. Budker Institute of Nuclear Physics of SB RAS, Lavrentyev prospect -11, 630090 Novosibirsk, Russia. Tel.: +7 3832 325229; fax: +7 3832 343321. E-mail address: [email protected] (E.L. Goldberg).
temperature increase [1–3]. The warm periods began extremely rapidly (for 40–80 yr [4,5] or even 10 yr in the Younger Dryas [6]) and lasted 400–2000 yr; the returns back to cold were almost as abrupt as the transitions to warming (Dansgaard-Oeschger events, D/O). Moreover, the Greenland and Canadian ice sheets were broken at least six times during the same period providing enormous discharge of calved icebergs into the Atlantic Ocean (Heinrich events, H) [7,8]. The
0168-9002/$ - see front matter r 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.nima.2005.01.242
ARTICLE IN PRESS E.L. Goldberg et al. / Nuclear Instruments and Methods in Physics Research A 543 (2005) 284–287
2. Methods and samples We measured the concentrations of Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Y, Zr, Nb, Mo, Pb, U, Th, Sn, Sb, Cs, Ba, La, Ce, and some other elements in 8 m of sedimentary core LV 28–40 retrieved at a depth of 1312 m at 51120, 045 N and 147110, 613 E in the age, ky 0
25
0
50
75
100 1.4
tephra K2
30
900
20
600
15 10
300
Sed. rate, cm/ ky
25 depth, cm
abrupt and prominent climate excursions were detected worldwide, including the equatorial and tropic zones and the northern Pacific [9–11]. They are synchronous over the Northern hemisphere, and in the Southern hemisphere the most prominent events are about 1000 yr in advance [12,13]. The events are not quite periodic with millennialscale pacings of 1–2 kyr (1500 yr cycle) or 4–6 kyr [8]. Neither mechanisms nor causes of synchronicity (asynchrony) of these climate shifts are clearly understood. The objective of this study was to obtain multielement data from the bottom sediments of the Okhotsk Sea with a 100–300 yr resolution and trace unambiguous evidence of the warm spells during last glacial time.
285
5 0
0 0
10
20
30
40 50 age, ky
60
70
80
90
Fig. 2. Age-depth model of core st28–40 and sedimentation rate (SR). The arrows point to the timing of Heinrich events H1–H7 (IRD in North Atlantic). As rule, SR is decreased over dry and cold H—events and increased during warmer periods due to elevated biogenic accumulation.
Okhotsk Sea. The applied SR XFA techniques and preliminary results of factor analysis of the collected multi-element data are reported in our companion paper [14]. Sampling interval was 1 cm for chemicals and 2–3 cm for other proxies. The age-depth model of the core was obtained by correlation of its magnetic susceptibility (MS) profile with the MS record of core st936 with reliable 14C ages [11] and by matching the volcanic glass horizons in the two cores (tephra K2 [11]). The correlated MS profiles of the two cores along with the marine d18O record [15] are shown in Fig. 1 and the age-depth model and sedimentation rate in Fig. 2.
20 0.9
3. Results and discussion 0.4
60 80
-0.1
δ18O, a.u.
MS, a.u.
40
100 -0.6 MS936 MS28_40 18O
120 140
-1.1 MIS1 MIS2
MIS3
MIS4
MIS5
Fig. 1. Correlation of magnetic susceptibility profiles in cores st28–40 and 936 [11] and ocean oxygen isotope profile [15]. Marine isotope stages are shown on the bottom panel. The arrows point to the most prominent eruption layers enriched by tephra K2 [11].
Biogenic Ba (Babio) in bottom sediments provides a reliable production proxy. It precipitates as biogenic barite from water during diagenesis of sinking particles of dead organic matter at great sea depths [16]. The content of Babio was estimated by subtraction of its terrigenous component (Bater) from the total bulk concentration in sediment. The terrigenous component, in turn, was found from empirical regional (Ba/Ti)ter ratios in the intervals with the lowest Batot contents: Babio ¼ Batot ðBa=TiÞter Ti: These intervals are also marked by the absence of biogenic carbonate and lowest organic carbon.
ARTICLE IN PRESS 286
E.L. Goldberg et al. / Nuclear Instruments and Methods in Physics Research A 543 (2005) 284–287 1000 Ba-bio (Ti)
H1
H2
H3
H4
H5
H6
H7
(a) 0 12
Ln(Mn)
11 10 9 8
(b)
7 1.5 Ln(Corg/0.394)
(c) 0.0 2 delta
18
O in Greenland Ice
-0.5
(d) -3 0
IS
10
1
2
20
3 4 567 8 9
30
12
14
40 50 age, ky
16
18
19
60
20
70
21
80
90
Fig. 3. The profiles of Bio production (Babio and Corg) and seawater ventilation (Mn) in the Okhotsk Sea on the age-depth scale of this study are correlated with air temperature above Greenland. The shaded lines point to the timing of Heinrich events H1–H7. Minimums of Bio production and Corg and elevated seawater ventilation in the Okhotsk Sea are synchronous with H-events in North Atlantic.
The (Ba/Ti)ter ratio of 0.145 obtained here for the Okhotsk Sea is consistent with the upper crust average of 0.130. Similarly, Babio contents were estimated using Bater normalized to K, Th, Rb, Nb, La, and Ce. The Babio profiles based on calibration to these typical terrigenous elements and their empirical regional ratios are almost identical. Fig. 3 shows SR XFA profiles of Babio, Corg, Mn and d18O concentrations in Greenland ice. The oxygen isotope record correlates with air temperatures above Greenland. Gray vertical bars mark the coldest and driest events (H-events). Low frequency trends of Babio and Corg are similar to PC2 trend, which characterize input of terrigenous material with Amur River waters [14]. Heinrich
events from H1 to H7 except H4 match bio production (Babio) and Corg minimums in the Okhotsk Sea. Abrupt Mn decrease in the same intervals point to either strengthening of ventilation of seawater during these periods or sudden increase of terrigenous sedimentation. In contrast, maximums of bio production (Babio) and Corg in the Okhotsk Sea match warm interstadials (D/O [1–3]) during the last glacial period.
4. Conclusions Thus the analyzed high-resolution multi-element records provide unambiguous evidence for almost
ARTICLE IN PRESS E.L. Goldberg et al. / Nuclear Instruments and Methods in Physics Research A 543 (2005) 284–287
synchronous response of the Okhotsk Sea to abrupt warm and cold events in the Atlantic.
Acknowledgements We wish to thank K.V. Zolotarev from the SR Center in INP (Novosibirsk) for help in treatments of XFA spectra and maintenance of the SR XFA scanning station. We are grateful to academicians G.N. Kulipanov and M.A. Grachev for overall support and concern in our work. Grants #121 and #175 from the Siberian Branch of the Russian Academy of Sciences and Grant #143 from SBRAS—FEBRAS funded this study. References [1] W. Dansgaard, et al., Nature 364 (1993) 218. [2] K.C. Taylor, G.W. Lamorey, G.A. Doyle, et al., Nature 361 (1993) 432.
287
[3] S.J. Johnsen, H.B. Clausen, W. Dansgaard, et al., Nature 359 (1992) 311. [4] Severenhaus, et al., Science 286 (1999) 930. [5] C. Lang, M. Leuenberger, J. Schwander, et al., Science 286 (1999) 934. [6] R.B. Alley, D.A. Meese, C.A. Shuman, et al., Nature 362 (1993) 527. [7] H. Heinrich, Quat. Res. 29 (1988) 142. [8] G.C. Bond, R. Lotti, Science 267 (1995) 1005. [9] I.L. Hendy, J.P. Kennett, Paleoceanography 15 (2000) 30. [10] T. Kiefer, M.S. Sarnthein, H. Erlenkeuser, et al., Paleoceanography 16 (2001) 179. [11] S.A. Gorbarenko, J.R. Southon, L.D. Keigwin, et al., Palaeogeogr., Paleoclimatol., Palaeoecol. 209 (2004) 281. [12] T. Blunier, E.J. Brook, Science 291 (2001) 109. [13] T. Blunier, et al., Nature 394 (1998) 739. [14] E.L. Goldberg, S.A. Gorbarenko, A.D. Shaporenko, et al., SRXFA for element composition of bottom sediments from the Okhotsk Sea, this issue, doi:10.1016/j.nima. 2005.01.241. [15] D.G. Martinson, N.G. Pisias, J.D. Hays, et al., Quat. Res. 27 (1987) 1. [16] J. Dymond, E. Suess, M. Lyle, Paleoceanography 7 (1992) 163.
Nuclear Instruments and Methods in Physics Research A 543 (2005) 284–287 www.elsevier.com/locate/nima
Instability of last glacial climate from SRXFA data for bottom sediments in the Okhotsk Sea E.L. Goldberga,c,, S.A. Gorbarenkob, A.D. Shaporenkoa,c, A.A. Bosinb, V.Yh. Leskovb, E.P. Chebykina a Limnological Institute of the SB RAS, 664033 Irkutsk, Russia Pacific Oceanological Institute of the FEB RAS, 690041 Vladivostok, Russia c Budker Institute of Nuclear Physics of SB RAS, Lavrentyev prospect -11, Budker, 630090 Novosibirsk, Russia b
Available online 3 March 2005
Abstract X-ray Fluorescence Analysis with Synchrotron Radiation (SR XFA) was used to study, at a high-resolution (200 yr), the behavior of elements in an 80 kyr core record from the Okhotsk Sea. We measured biogenic Ba (BaBio), biogenic carbonate, and organic carbon as bio production indicators, elements that record the Amur terrigenous input, and Mn as signature of water ventilation and redox conditions at the sediment/water interface. The Okhotsk Sea in last glacial time responded to abrupt warm spells in the Atlantic and Greenland. Bio production in the Okhotsk Sea increased dramatically during warm D/O events and decreased during cold and dry H-events. r 2005 Elsevier B.V. All rights reserved. PACS: 07.85.Qe; 92.70.Gt; 92.40.Ni; 91.65.Rg Keywords: Synchrotron radiation; Okhotsk sea; Last glacial period; Millennial scale oscillations; Dansgaard-Oeschger and Henrich events; Biogenic barium
1. Introduction We can be now positive that the last glacial period (24–74 kyr) in Greenland was interrupted by at least 19 warm spells with a 12–15 1C Corresponding author. Budker Institute of Nuclear Physics of SB RAS, Lavrentyev prospect -11, 630090 Novosibirsk, Russia. Tel.: +7 3832 325229; fax: +7 3832 343321. E-mail address: [email protected] (E.L. Goldberg).
temperature increase [1–3]. The warm periods began extremely rapidly (for 40–80 yr [4,5] or even 10 yr in the Younger Dryas [6]) and lasted 400–2000 yr; the returns back to cold were almost as abrupt as the transitions to warming (Dansgaard-Oeschger events, D/O). Moreover, the Greenland and Canadian ice sheets were broken at least six times during the same period providing enormous discharge of calved icebergs into the Atlantic Ocean (Heinrich events, H) [7,8]. The
0168-9002/$ - see front matter r 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.nima.2005.01.242
ARTICLE IN PRESS E.L. Goldberg et al. / Nuclear Instruments and Methods in Physics Research A 543 (2005) 284–287
2. Methods and samples We measured the concentrations of Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Y, Zr, Nb, Mo, Pb, U, Th, Sn, Sb, Cs, Ba, La, Ce, and some other elements in 8 m of sedimentary core LV 28–40 retrieved at a depth of 1312 m at 51120, 045 N and 147110, 613 E in the age, ky 0
25
0
50
75
100 1.4
tephra K2
30
900
20
600
15 10
300
Sed. rate, cm/ ky
25 depth, cm
abrupt and prominent climate excursions were detected worldwide, including the equatorial and tropic zones and the northern Pacific [9–11]. They are synchronous over the Northern hemisphere, and in the Southern hemisphere the most prominent events are about 1000 yr in advance [12,13]. The events are not quite periodic with millennialscale pacings of 1–2 kyr (1500 yr cycle) or 4–6 kyr [8]. Neither mechanisms nor causes of synchronicity (asynchrony) of these climate shifts are clearly understood. The objective of this study was to obtain multielement data from the bottom sediments of the Okhotsk Sea with a 100–300 yr resolution and trace unambiguous evidence of the warm spells during last glacial time.
285
5 0
0 0
10
20
30
40 50 age, ky
60
70
80
90
Fig. 2. Age-depth model of core st28–40 and sedimentation rate (SR). The arrows point to the timing of Heinrich events H1–H7 (IRD in North Atlantic). As rule, SR is decreased over dry and cold H—events and increased during warmer periods due to elevated biogenic accumulation.
Okhotsk Sea. The applied SR XFA techniques and preliminary results of factor analysis of the collected multi-element data are reported in our companion paper [14]. Sampling interval was 1 cm for chemicals and 2–3 cm for other proxies. The age-depth model of the core was obtained by correlation of its magnetic susceptibility (MS) profile with the MS record of core st936 with reliable 14C ages [11] and by matching the volcanic glass horizons in the two cores (tephra K2 [11]). The correlated MS profiles of the two cores along with the marine d18O record [15] are shown in Fig. 1 and the age-depth model and sedimentation rate in Fig. 2.
20 0.9
3. Results and discussion 0.4
60 80
-0.1
δ18O, a.u.
MS, a.u.
40
100 -0.6 MS936 MS28_40 18O
120 140
-1.1 MIS1 MIS2
MIS3
MIS4
MIS5
Fig. 1. Correlation of magnetic susceptibility profiles in cores st28–40 and 936 [11] and ocean oxygen isotope profile [15]. Marine isotope stages are shown on the bottom panel. The arrows point to the most prominent eruption layers enriched by tephra K2 [11].
Biogenic Ba (Babio) in bottom sediments provides a reliable production proxy. It precipitates as biogenic barite from water during diagenesis of sinking particles of dead organic matter at great sea depths [16]. The content of Babio was estimated by subtraction of its terrigenous component (Bater) from the total bulk concentration in sediment. The terrigenous component, in turn, was found from empirical regional (Ba/Ti)ter ratios in the intervals with the lowest Batot contents: Babio ¼ Batot ðBa=TiÞter Ti: These intervals are also marked by the absence of biogenic carbonate and lowest organic carbon.
ARTICLE IN PRESS 286
E.L. Goldberg et al. / Nuclear Instruments and Methods in Physics Research A 543 (2005) 284–287 1000 Ba-bio (Ti)
H1
H2
H3
H4
H5
H6
H7
(a) 0 12
Ln(Mn)
11 10 9 8
(b)
7 1.5 Ln(Corg/0.394)
(c) 0.0 2 delta
18
O in Greenland Ice
-0.5
(d) -3 0
IS
10
1
2
20
3 4 567 8 9
30
12
14
40 50 age, ky
16
18
19
60
20
70
21
80
90
Fig. 3. The profiles of Bio production (Babio and Corg) and seawater ventilation (Mn) in the Okhotsk Sea on the age-depth scale of this study are correlated with air temperature above Greenland. The shaded lines point to the timing of Heinrich events H1–H7. Minimums of Bio production and Corg and elevated seawater ventilation in the Okhotsk Sea are synchronous with H-events in North Atlantic.
The (Ba/Ti)ter ratio of 0.145 obtained here for the Okhotsk Sea is consistent with the upper crust average of 0.130. Similarly, Babio contents were estimated using Bater normalized to K, Th, Rb, Nb, La, and Ce. The Babio profiles based on calibration to these typical terrigenous elements and their empirical regional ratios are almost identical. Fig. 3 shows SR XFA profiles of Babio, Corg, Mn and d18O concentrations in Greenland ice. The oxygen isotope record correlates with air temperatures above Greenland. Gray vertical bars mark the coldest and driest events (H-events). Low frequency trends of Babio and Corg are similar to PC2 trend, which characterize input of terrigenous material with Amur River waters [14]. Heinrich
events from H1 to H7 except H4 match bio production (Babio) and Corg minimums in the Okhotsk Sea. Abrupt Mn decrease in the same intervals point to either strengthening of ventilation of seawater during these periods or sudden increase of terrigenous sedimentation. In contrast, maximums of bio production (Babio) and Corg in the Okhotsk Sea match warm interstadials (D/O [1–3]) during the last glacial period.
4. Conclusions Thus the analyzed high-resolution multi-element records provide unambiguous evidence for almost
ARTICLE IN PRESS E.L. Goldberg et al. / Nuclear Instruments and Methods in Physics Research A 543 (2005) 284–287
synchronous response of the Okhotsk Sea to abrupt warm and cold events in the Atlantic.
Acknowledgements We wish to thank K.V. Zolotarev from the SR Center in INP (Novosibirsk) for help in treatments of XFA spectra and maintenance of the SR XFA scanning station. We are grateful to academicians G.N. Kulipanov and M.A. Grachev for overall support and concern in our work. Grants #121 and #175 from the Siberian Branch of the Russian Academy of Sciences and Grant #143 from SBRAS—FEBRAS funded this study. References [1] W. Dansgaard, et al., Nature 364 (1993) 218. [2] K.C. Taylor, G.W. Lamorey, G.A. Doyle, et al., Nature 361 (1993) 432.
287
[3] S.J. Johnsen, H.B. Clausen, W. Dansgaard, et al., Nature 359 (1992) 311. [4] Severenhaus, et al., Science 286 (1999) 930. [5] C. Lang, M. Leuenberger, J. Schwander, et al., Science 286 (1999) 934. [6] R.B. Alley, D.A. Meese, C.A. Shuman, et al., Nature 362 (1993) 527. [7] H. Heinrich, Quat. Res. 29 (1988) 142. [8] G.C. Bond, R. Lotti, Science 267 (1995) 1005. [9] I.L. Hendy, J.P. Kennett, Paleoceanography 15 (2000) 30. [10] T. Kiefer, M.S. Sarnthein, H. Erlenkeuser, et al., Paleoceanography 16 (2001) 179. [11] S.A. Gorbarenko, J.R. Southon, L.D. Keigwin, et al., Palaeogeogr., Paleoclimatol., Palaeoecol. 209 (2004) 281. [12] T. Blunier, E.J. Brook, Science 291 (2001) 109. [13] T. Blunier, et al., Nature 394 (1998) 739. [14] E.L. Goldberg, S.A. Gorbarenko, A.D. Shaporenko, et al., SRXFA for element composition of bottom sediments from the Okhotsk Sea, this issue, doi:10.1016/j.nima. 2005.01.241. [15] D.G. Martinson, N.G. Pisias, J.D. Hays, et al., Quat. Res. 27 (1987) 1. [16] J. Dymond, E. Suess, M. Lyle, Paleoceanography 7 (1992) 163.