| Chemical analyses of Nyiragongo lavas | |||||||
| Geodynamic context: | Rift | ||||||
| Rift zone: | East African Rift System | ||||||
| Rift zone target: | Western Branch (WB) | ||||||
| Locality: | Goma (North Kivu)/DRC | ||||||
| Volcano: | Nyiragongo | ||||||
| Volcano type: | Stratovolcano | ||||||
| Samples | DM 14UM -Nyira. 2002-1 | DM 14UM -Nyira. 1977-1 | DM 14UM -Nyira. 2002-2 | DM 14UM -Nyira. 1977-2 | DM 14UM -Nyira. 2002-3 | DM 14UM -Nyira. 1977-3 | DM 14UM -Nyira. 2002-4 |
| Major elements |
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| SiO2 (wt%) | 38.4 | 38.6 | 39 | 38.5 | 38.7 | 38.4 | 39.5 |
| Al2O3 (wt%) | 16.5 | 16.2 | 16.2 | 16.5 | 16.2 | 16.2 | 15 |
| FeOt (wt%) | 14.1 | 14 | 14 | 14.1 | 13.8 | 14.1 | 13.8 |
| MnO (wt%) | 0.2 | 0.2 | 0.2 | 0.1 | 0.2 | 0.1 | 0.3 |
| MgO (wt%) | 3.1 | 3 | 3.2 | 3 | 3 | 3 | 4 |
| K2O (wt%) | 5.5 | 5.5 | 5.2 | 5.4 | 5.6 | 5.8 | 5.3 |
| CaO (wt%) | 11.1 | 11 | 11.2 | 11.1 | 11 | 11.7 | 12.3 |
| TiO2 (wt%) | 2.1 | 2 | 1.6 | 1.8 | 2.1 | 1.8 | 1.9 |
| Na2O (wt%) | 6 | 6 | 6 | 6.1 | 6 | 6.1 | 5 |
| P2O5 (wt%) | 1.5 | 1.6 | 1.6 | 1.6 | 1.6 | 1.5 | 1.7 |
| H2O (wt%) | 1.5 | 1.5 | 1.4 | 1.4 | 1.6 | 1 | 1 |
| Total (wt%) | 100.0 | 99.6 | 99.6 | 99.6 | 99.8 | 99.7 | 99.8 |
| Na2O + K2O (wt%) | 11.5 | 11.5 | 11.2 | 11.5 | 11.6 | 11.9 | 10.3 |
| Na2O/K2O | 1.1 | 1.1 | 1.2 | 1.1 | 1.1 | 1.1 | 0.9 |
| Mg# [Mg/(Mg + Fe)] | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 |
| Minor elements |
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| Ni (ppm) | 40 | 42 | 48 | 45 | 42 | 50 | 40 |
| Sn (ppm) | 1 | 2 | 2 | 1 | 2 | 2 | 1 |
| Sc (ppm) | 4 | 4 | 4 | 4 | 4 | 4 | 4 |
| Be (ppm) | 3 | 3 | 3 | 3 | 3 | 3 | 3 |
| V (ppm) | 450 | 402 | 355 | 303 | 505 | 313 | 309 |
| Ba (ppm) | 2002 | 1989 | 2120 | 2049 | 1999 | 2103 | 2157 |
| Sr (ppm) | 2615 | 2357 | 2500 | 2480 | 2090 | 2398 | 2502 |
| Cr (ppm) | 20 | 15 | 17 | 16 | 19 | 21 | 20 |
| Zr (ppm) | 351 | 340 | 339 | 401 | 299 | 322 | 345 |
| Co (ppm) | 22 | 38 | 33 | 45 | 40 | 29 | 41 |
| Cu (ppm) | 203 | 211 | 175 | 169 | 191 | 185 | 180 |
| Zn (ppm) | 245 | 203 | 148 | 122 | 195 | 205 | 130 |
| Ga (ppm) | 11 | 15 | 21 | 28 | 16 | 24 | 19 |
| Ge (ppm) | 1 | 8 | 1 | 2 | 1 | 1 | 1 |
| As (ppm) | 4 | 1 | 1 | 2 | 4 | 5 | 5 |
| Rb (ppm) | 99 | 88 | 89 | 108 | 122 | 106 | 124 |
| Nb (ppm) | 199 | 218 | 160 | 201 | 180 | 211 | 202 |
| Mo (ppm) | 1 | 1 | 3 | 2 | 5 | 1 | 4 |
| Ag (ppm) | 1 | 1 | 1 | 2 | 1 | 1 | 1 |
| In (ppm) | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Sb (ppm) | 1 | 0 | 0 | 1 | 0 | 0 | 1 |
| Cs (ppm) | 1 | 1 | 2 | 1 | 1 | 1 | 1 |
| Hf (ppm) | 4 | 4 | 5 | 4 | 5 | 5 | 4 |
| Ta (ppm) | 10 | 13 | 16 | 13 | 14 | 12 | 13 |
| W (ppm) | 1 | 2 | 1 | 2 | 1 | 1 | 1 |
| Tl (ppm) | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Pb (ppm) | 6 | 7 | 5 | 6 | 6 | 7 | 5 |
| Bi (ppm) | 0 | 0 | 0 | 1 | 0 | 0 | 0 |
| Th (ppm) | 22 | 20 | 18 | 20 | 15 | 17 | 18 |
| U (ppm) | 7 | 7 | 5 | 4 | 5 | 7 | 6 |
| La (ppm) | 182 | 195 | 166 | 180 | 168 | 195 | 182 |
| Ce (ppm) | 355 | 361 | 341 | 401 | 323 | 399 | 344 |
| Pr (ppm) | 30 | 35 | 34 | 37 | 35 | 31 | 36 |
| Nd (ppm) | 128 | 133 | 121 | 122 | 128 | 125 | 125 |
| Sm (ppm) | 15 | 13 | 18 | 19 | 22 | 13 | 18 |
| Eu (ppm) | 6 | 7 | 5 | 6 | 6 | 6 | 5 |
| Gd (ppm) | 10 | 11 | 10 | 12 | 12 | 12 | 11 |
| Tb (ppm) | 1 | 1 | 1 | 1 | 2 | 2 | 2 |
| Dy (ppm) | 6 | 7 | 8 | 9 | 8 | 8 | 8 |
| Ho (ppm) | 1 | 1 | 2 | 2 | 1 | 2 | 1 |
| Er (ppm) | 3 | 3 | 4 | 4 | 4 | 4 | 4 |
| Tm (ppm) | 0 | 0 | 1 | 0 | 1 | 1 | 1 |
| Yb (ppm) | 3 | 3 | 3 | 2 | 3 | 3 | 3 |
| Lu (ppm) | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Y (ppm) | 19 | 22 | 45 | 39 | 32 | 40 | 36 |
| ∑REE (ppm) | 742 | 770 | 712 | 795 | 713 | 799 | 739 |