grl29472-sup-0002-txts01

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Auxiliary Materials: Tsuno et al. (2012) – Geophys. Res. Lett. vol. 39; doi: 10.1029/2012GL052606
Flux of carbonate melt from deeply subducted pelitic sediments – geophysical and
geochemical implications for the source of Central American volcanic arc
Kyusei Tsuno1, Rajdeep Dasgupta1, Lisa Danielson2, Kevin Righter3
1
Department of Earth Science, Rice University, 6100 Main Street, MS 126, Houston, TX 77005,
USA
2
ESCG, Mail Code JE23, 2101 NASA Parkway, Houston, TX 77058, USA
3
NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX 77058, USA
Multi anvil experiments
Experiments at 4-7 GPa and 900-1100 °C were performed using a Walker-type multi-anvil (MA)
apparatus at NASA-JSC, and a COMPRES G2 cell assembly [Leinenweber et al., 2012]. The
MA pressure calibration was conducted using the quartz-coesite transformation at 3.1 GPa and
1000 °C [Bose and Ganguly, 1995], Fe2SiO4 olivine-spinel transition at 5.8 GPa and 1200 °C
[Yagi et al., 1987], and CaGeO3 garnet-perovskite transition at 6.1 GPa and 1000 °C [Ono et al.,
2011].
Page 1 of 5
Auxiliary Materials: Tsuno et al. (2012) – Geophys. Res. Lett. vol. 39; doi: 10.1029/2012GL052606
Supplementary Table 1: Compositions of the sedimentary starting materials (in wt.%)
SiO2
TiO2
Al2O3
FeO*
MnO
MgO
CaO
Na2O
K2O
P 2O5
H2O
CO2
Mg#
Total
HPLC3a
54.0
0.7
15.0
7.3
0.2
2.9
9.6
2.2
2.0
-
1.0
5.0
41.9
100.0
HPLC4a
54.3
0.7
15.0
7.4
0.2
3.0
9.7
2.2
2.0
-
0.5
5.0
42.0
100.0
HPLC2b
60.0
0.6
12.5
6.1
0.2
2.5
8.0
2.2
2.0
-
1.0
5.0
42.1
100.0
TS08, GS11c
47.6
-
22.8
9.2
-
2.0
6.8
2.4
3.6
-
1.1
4.8
28.1
100.0
10GC-90GDMd
51.5
0.5
10.7
5.4
0.2
2.1
6.9
1.9
1.7
0.1
14.6
4.3
41.5
100.0
a
Fluid present (HPLC3) and fluid-absent (HPLC4) starting compositions used in this study, which simulate bulk compositions from which siliceous water vapor
has been extracted in shallow part of subduction.
b
The starting composition used in Tsuno and Dasgupta [2012], which simulates significant dehydration of 10GC-90DGM during shallow part of Central American
subduction, on a volatile-free basis, is also similar to the bulk composition of the sediment columns that subduct at the trenches of Vanuatu, E. Sunda,
and Makran (see Figure 1 of Tsuno and Dasgupta [2012]).
c
The starting composition used in Thomsen and Schmidt [2008] and Grassi and Schmidt [2011a, b], which is similar to the alumina-rich, Fe-calcareous clay
composition that subducts at the trench of Lesser Antilles [Plank and Langmuir , 1998].
d
The model composition, a mixture of 10 wt.% Guatemalan carbonated (GC) unit and 90 wt.% Guatemalan diatomaceous mud (GDM) unit that subducts
at the Central American trench (see Plank and Langmuir [1998]).
Supplementary Table 2. Phase compositions from partial melting experiments on HPLC3 and HPLC4 at 5-7 GPa a
Run No. P (GPa) T (°C)
Phases
(HPLC3: pelite + 1 wt.% H2O and 5.0 wt.% CO2)
BJJB156
5
900
cpx
garnet
phengite
calcitess
BJJB176
5
950
cpx
garnet
phengite
calcitess
carbonate melt
BJJB155
5
1000
cpx
garnet
phengite
carbonate melt
BJJB178
5
1050
cpx
garnet
BJJB157
BJJB177
5
7
1100
1000
Na2O-calcc
n
SiO2
TiO2
Al2O3
FeO*
MnO
MgO
CaO
Na2O
K2O
CO2
H2O
Total
4
4
4
5
5
4
4
5
4
4
5
2
3
6
5
59.2(2)
40.2(2)
54.3(7)
0.08(2)
57.3(7)
39.6(3)
52.3(7)
0.07(7)
0.61(29)
57.5(9)
40.0(3)
52.6(5)
0.42(18)
55.9(8)
39.7(2)
0.17(3)
0.48(4)
0.90(3)
0.04(1)
0.24(4)
0.65(6)
2.0(5)
0.02(2)
0.19(5)
0.32(9)
0.68(9)
2.6(5)
0.20(12)
0.38(8)
0.47(4)
20.8(3)
22.3(1)
24.9(6)
0.02(2)
20.0(3)
22.2(1)
23.7(10)
0.04(4)
0.92(5)
19.1(5)
22.7(1)
25.0(2)
0.53(13)
18.1(4)
22.6(3)
1.3(1)
17.3(5)
1.9(1)
6.3(5)
1.6(1)
17.8(3)
2.4(3)
0.13(3)
9.3(14)
2.2(1)
16.4(5)
2.1(1)
7.8(4)
2.6(2)
17.0(3)
0.06(4)
0.79(5)
0.00(1)
0.05(5)
0.03(1)
0.86(3)
0.01(1)
0.02(3)
0.32(17)
0.06(4)
0.77(4)
0.04(1)
0.28(3)
0.01(4)
1.0(2)
3.00(2)
5.23(2)
4.2(1)
9.8(5)
3.7(1)
5.3(1)
3.8(2)
0.00(0)
5.4(1)
3.8(2)
4.7(2)
3.2(1)
3.5(5)
3.8(1)
5.2(2)
6.2(2)
14.8(4)
0.13(7)
39.1(5)
6.6(2)
15.2(3)
0.13(3)
55.6(6)
34.9(6)
8.5(2)
16.0(7)
0.06(2)
36.2(3)
9.6(1)
15.8(1)
11.0(3)
0.16(3)
0.08(1)
0.01(1)
10.6(4)
0.21(2)
0.07(2)
0.06(3)
0.81(10)
9.0(3)
0.20(3)
0.13(2)
6.0(4)
8.4(1)
0.18(6)
0.03(1)
0.04(4)
11.1(3)
0.05(4)
0.12(6)
0.12(4)
10.8(2)
0.12(4)
5.6(20)
0.13(5)
0.04(5)
11.1(5)
3.2(6)
0.04(2)
0.01(1)
45.2(4)
-
4.51(1)
101.6
101.3
102.0
100.7
100.2
101.9
99.6
99.7
58.0
100.5
101.6
101.4
58.2
98.8
102.0
silicate meltb
carbonate melt
cpx
garnet
8
2
7
7
55.3(7)
0.37(20)
56.0(4)
38.9(2)
2.1(6)
2.1(2)
0.37(5)
0.68(11)
10.3(2)
0.33(21)
19.7(4)
22.3(2)
8.7(2)
6.5(14)
2.4(2)
16.5(2)
0.28(4)
0.25(1)
0.03(3)
0.76(4)
1.6(1)
2.5(6)
3.4(2)
5.0(1)
11.2(1)
39.8(5)
8.7(3)
16.1(3)
3.2(1)
0.63(12)
8.7(2)
0.20(3)
7.4(4)
1.5(6)
0.04(2)
0.01(1)
silicate meltb
carbonate melt
cpx
garnet
carbonate melt
8
2
7
7
3
51.4(3)
0.48(2)
57.0(2)
38.9(2)
1.9(15)
3.2(1)
3.0(2)
0.3(1)
0.95(3)
1.1(1)
11.9(2)
1.3(3)
20.5(4)
22.1(2)
0.97(33)
5.0(1)
8.3(1)
2.2(1)
16.8(1)
7.5(15)
0.13(3)
0.25(1)
0.05(3)
1.7(1)
0.25(10)
1.7(0)
3.2(2)
2.7(2)
2.6(3)
4.6(11)
13.5(2)
37.9(4)
6.1(3)
16.7(1)
34.3(18)
1.9(2)
0.47(4)
9.8(3)
0.13(2)
2.7(12)
11.2(3)
0.76(2)
0.06(1)
0.06(0)
5.9(10)
79.3
55.6
98.6
99.9
58.2
4.7
6
6
5
7
7
4
5
2
6
9
8
3
58.1(9)
39.9(1)
66.1(4)
52.0(4)
0.03(1)
57.5(4)
38.4(3)
52.4(3)
0.03(1)
57.0(4)
39.7(2)
0.98(73)
0.12(2)
0.36(4)
0.00
0.92(4)
0.02(2)
0.20(2)
0.64(22)
2.5(2)
0.03(3)
0.26(5)
0.62(12)
3.0(2)
20.8(4)
22.6(2)
18.44(5)
23.4(0)
0.14(3)
20.1(5)
21.9(1)
25.3(4)
0.14(1)
19.3(4)
22.6(2)
1.3(3)
1.4(1)
18.8(6)
0.15(2)
2.0(1)
8.2(7)
2.2(1)
21.0(12)
2.1(1)
5.3(4)
2.4(2)
17.1(3)
8.3(1)
0.04(3)
0.83(8)
0.00(0)
0.00(0)
0.32(4)
0.07(2)
1.1(1)
0.02(3)
0.3(4)
0.07(3)
0.82(3)
0.41(2)
2.9(2)
5.6(3)
0.00(0)
4.2(1)
11.2(3)
3.2(4)
4.1(2)
2.4(3)
7.2(1)
4.9(2)
6.1(5)
3.2(2)
5.4(4)
13.9(5)
0.13(1)
0.19(17)
35.1(5)
6.2(5)
12.1(10)
0.06(1)
42.0(6)
7.2(2)
14.5(7)
25.4(3)
11.2(2)
0.12(2)
0.31(10)
0.07(4)
0.13(4)
10.1(4)
0.23(5)
0.17(6)
0.13(4)
9.9(2)
0.19(3)
0.47(4)
0.12(2)
0.07(1)
16.6(14)
11.1(2)
0.18(7)
0.10(3)
0.19(5)
11.0(2)
0.22(6)
0.14(11)
0.03(2)
18.3(7)
100.1
102.1
101.7
98.4
100.0
99.6
99.6
100.4
99.3
101.1
101.6
61.3
7.2
(HPLC4: pelite + 0.5 wt.% H 2O and 5.0 wt.% CO2)
BJJB198
5
900
cpx
garnet
K-feldspar
phengite
calcitess
BJJB194
5
950
cpx
garnet
phengite
calcitess
BJJB193
5
1000
cpx
garnet
carbonate melt
a
Numbers in parentheses are one standard deviation in terms of last digit(s). For example, 59.2(2) should be read as 59.2 ± 0.2 wt.%.
b
Silicate melt compositions are reported on a volatile-free basis. The microprobe total is also shown.
c
Na2O contents of carbonate melts based on the mass balance calculations [Yaxley and Green , 1996]
Page 2 of 5
4.5(1)
43.7(4)
-
4.5(2)
-
-
-
-
4.5(1)
44.7(4)
4.5(1)
44.0(2)
9.7
11.4
84.6
53.9
99.3
100.3
Auxiliary Materials: Tsuno et al. (2012) – Geophys. Res. Lett. vol. 39; doi: 10.1029/2012GL052606
Figure S1. (a) Jadeite (NaAlSi3O8) and (b) Calcium-Tschermak component in clinopyroxene
(cpx) as a function of temperature from 5 GPa melting experiments of carbonated pelite. Solid
circles and squares (in red) are data from our lower-alumina bulk compositions HPLC3 and
HPLC4, respectively and open diamonds are data from high aluminous bulk composition of
Thomsen and Schmidt [2008] (at 5.0 GPa) and Grassi and Schmidt [2011]. Higher alumina bulk
composition results in cpx with higher aluminous components at a given P-T condition which in
turn elevate bulk partition coefficient of Na between pelite and carbonatitic melt, thereby
minimizing the influence of Na in stabilizing a carbonate melt.
Page 3 of 5
Auxiliary Materials: Tsuno et al. (2012) – Geophys. Res. Lett. vol. 39; doi: 10.1029/2012GL052606
Figure S2. Estimated (a) Na2O (wt.%), (b) K2O (wt.%), and (c) total alkali concentrations of
carbonatite melt as a function of temperature from 5 GPa melting experiments of carbonated
pelite. The symbols used here are the same as those in Figure S1. The higher alkali contents of
carbonatite melt at lower temperatures in our study are caused by the lower bulk partition
coefficient of Na between pelite and carbonatitic melt, which in turn is the result of stability of
less aluminous cpx in our lower alumina bulk compositions.
References
Bose, K., and J. Ganguly (1995), Quartz-coesite transition revisited: Reversed experimental
determination at 500-1200 °C and retrieved thermochemical properties, Am. Mineral., 80,
231–238.
Grassi, D and M. W. Schmidt (2011), The Melting of Carbonated Pelites from 70 to 700 km
Depth, J Petrol., 52, 765–789.
Leinenweber, K. D., J. A. Tyburczy, T. G. Sharp, E. Soignard, T. Diedrich, W. B. Petuskey, Y.
Wang, and J. L. Mosenfelder (2012), Cell assemblies for reproducible multi-anvil
experiments (the COMPRES assemblies), Am. Mineral., 97, 353–368.
Ono, S., T. Kikegawa, and Y. Higo (2011), In situ observation of a garnet/perovskite transition in
CaGeO3, Phys, Chem. Miner., 38, 735–740.
Thomsen, T. B., and M. W. Schmidt (2008), Melting of carbonated pelites at 2.5-5.0 GPa,
silicate-carbonatite liquid immiscibility, and potassium-carbon metasomatism of the mantle.
Earth Planet. Sci. Lett., 267, 17–31.
Yaxley, G. M., and D. H. Green (1996), Experimental reconstruction of sodic dolomitic
carbonatite melts from metasomatised lithosphere, Contrib. Mineral. Petrol., 124, 359–369.
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Auxiliary Materials: Tsuno et al. (2012) – Geophys. Res. Lett. vol. 39; doi: 10.1029/2012GL052606
Yagi, T., M. Akaogi, O. Shimomura, T. Suzuki, and S.‐I. Akimoto (1987), In Situ Observation of the
Olivine‐Spinel Phase Transformation in FeSiO Using Synchrotron Radiation, J. Geophys. Res., 92,
B7, doi:10.1029/JB092iB07p06207.
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