Region / Chatham Islands / South Island
Unit / Chatham Islands / Timaru / Deborah Volcanics / Dunedin Volcanics
Type / Basanite / Basanite / Potassic Trachybasalt / Basaltic Andesite / Tholeiitic Basalt / Basaltic Andesite / Basanite / Basanite
long / 176.6409 / 176.6348 / 176.3282 / 171.2523 / 170.9809 / 170.8557 / 170.5004 / 170.4861
lat / -43.7974 / -43.8074 / -44.0419 / -44.3772 / -45.1122 / -45.3584 / -45.5699 / -45.9188
Age / 5.2 ± 0.2 Ma / 79 ± 2 Ma / 77.9 ± 1.6 Ma / 2.47 ± 0.37 Ma / ~ 34 Ma / 40 - 32 Ma / 16.4? Ma / ~ 13 Ma
Age ref. / A / A / A / B; C / A; D / D / A / A
SiO2 / 41.4 / 43.9 / 47.3 / 52.6 / 50.2 / 50.3 / 43.8 / 43.2
TiO2 / 3.37 / 3.23 / 3.55 / 1.44 / 1.82 / 2.00 / 2.46 / 2.85
Al2O3 / 13.6 / 11.7 / 16.1 / 13.4 / 14.6 / 13.7 / 13.8 / 14.9
Fe2O3t / 13.5 / 13.9 / 12.64 / 12.2 / 11.2 / 10.2 / 12.4 / 13.2
MgO / 8.70 / 11.1 / 3.83 / 7.58 / 7.20 / 4.51 / 9.30 / 7.42
MnO / 0.170 / 0.180 / 0.15 / 0.160 / 0.150 / 0.140 / 0.19 / 0.200
CaO / 11.7 / 8.62 / 8.15 / 8.84 / 8.65 / 7.91 / 10.2 / 11.5
Na2O / 2.27 / 2.96 / 3.56 / 2.46 / 3.31 / 3.35 / 3.99 / 2.76
K2O / 1.57 / 1.48 / 1.70 / 0.270 / 0.630 / 0.730 / 1.68 / 1.19
P2O5 / 0.694 / 1.03 / 0.689 / 0.104 / 0.274 / 0.274 / 0.614 / 0.595
SO2 / 0.114 / 0.031 / 0.035 / 0.040 / 0.044 / 0.103 / 0.079 / 0.086
LOI / 1.97 / 0.42 / 1.08 / <0.1 / 0.95 / 5.57 / 0.54 / 0.79
Total / 99.0 / 98.5 / 98.8 / 98.7 / 98.9 / 98.8 / 99.1 / 98.6
FeO / 6.86 / 7.96 / 4.06 / 8.34 / 6.43 / 7.72 / 7.37 / 7.17
Mg# / 69.9 / 71.7 / 63.2 / 62.0 / 67.1 / 52.7 / 69.5 / 65.3
Cr / 256 / 533 / 34.4 / 364 / 277 / 165 / 340 / 203
Co / 57.0 / 53.5 / 34.6 / 49.7 / 45.2 / 32.0 / 46.9 / 44.0
Ni / 138 / 460 / 43.0 / 218 / 164 / 37.0 / 216 / 94.0
Rb / 34.1 / 29.8 / 33.7 / 8.03 / 9.91 / 14.0 / 41.1 / 30.0
Sr / 937 / 1065 / 837 / 173 / 377 / 457 / 904 / 750
Zr / 282 / 453 / 353 / 78.0 / 139 / 154 / 335 / 231
Nb / 84.5 / 98.9 / 58.1 / 8.00 / 23.9 / 20.0 / 124 / 64.0
Sc / 28.8 / 21.0 / 17.6 / 29.2 / 22.6 / 27.0
V / 375 / 232 / 283 / 207 / 188 / 242
Y / 28.9 / 35.5 / 30.4 / 20.1 / 18.6 / 28.1
Cs / 0.508 / 0.265 / 0.606 / 0.226 / 0.244 / 0.640
Ba / 479 / 396 / 335 / 75.0 / 125 / 477
La / 65.4 / 74.8 / 40.6 / 6.59 / 13.5 / 55.0
Ce / 135 / 146 / 90.8 / 13.8 / 28.7 / 111
Pr / 14.8 / 17.1 / 11.3 / 1.98 / 3.66 / 11.8
Nd / 55.6 / 68.1 / 45.9 / 9.26 / 15.7 / 44.0
Sm / 10.3 / 13.1 / 9.47 / 2.95 / 3.99 / 8.20
Eu / 3.14 / 4.09 / 3.10 / 1.22 / 1.48 / 2.58
Gd / 9.41 / 11.9 / 8.95 / 3.74 / 4.33 / 7.71
Tb / 1.24 / 1.57 / 1.24 / 0.63 / 0.660 / 1.07
Dy / 6.27 / 7.87 / 6.52 / 3.84 / 3.73 / 5.69
Ho / 1.07 / 1.32 / 1.13 / 0.721 / 0.674 / 1.03
Er / 2.60 / 3.24 / 2.82 / 1.87 / 1.71 / 2.68
Tm / 0.324 / 0.398 / 0.363 / 0.259 / 0.228 / 0.368
Yb / 2.00 / 2.41 / 2.26 / 1.64 / 1.43 / 2.36
Lu / 0.272 / 0.327 / 0.303 / 0.230 / 0.197 / 0.337
Hf / 5.41 / 8.57 / 7.01 / 2.22 / 2.97 / 6.14
Ta / 3.95 / 4.11 / 3.03 / 0.400 / 1.197 / 5.164
Pb / 4.84 / 3.62 / 3.37 / 1.38 / 2.21 / 3.85
Th / 9.09 / 7.24 / 5.21 / 1.22 / 2.38 / 8.30
U / 3.76 / 2.09 / 0.940 / 0.289 / 0.654 / 2.22
Sample / NZ557 / NZ560A / NZ561 / D111 / D113 / D117 / NZ568
Region / South Island / North Island
Unit / Dunedin Volcanics / Banks Peninsula / Alexandra Volcanics
Type / Basanite / Alkali Basalt / Alkali Basalt / Hawaiite / Tholeiitic Basalt / Basanite / Basanite
long / 170.2291 / 170.7121 / 170.4772 / 172.7451 / 172.7196 / 172.5598 / 174.9168
lat / -45.7591 / -45.8763 / -45.7969 / -43.5625 / -43.6344 / -43.7049 / -37.8135
Age / 16 ± 7 Ma / ~ 13 Ma / 12.1 - 11.2 Ma / 10 ± 0.3 Ma / 5.8 - 7 Ma / ~ 8 Ma / 2.7 - 1.8 Ma
Ageref. / A / A / D / A / J / A / E
SiO2 / 43.7 / 44.2 / 45.7 / 47.9 / 48.2 / 44.2 / 43.8
TiO2 / 2.39 / 2.66 / 2.33 / 2.51 / 1.92 / 2.97 / 2.33
Al2O3 / 13.3 / 12.7 / 15.1 / 16.0 / 13.7 / 13.4 / 11.8
Fe2O3t / 14.0 / 13.1 / 13.7 / 11.9 / 12.4 / 13.7 / 12.7
MgO / 9.54 / 9.81 / 7.03 / 5.59 / 9.74 / 9.13 / 13.4
MnO / 0.190 / 0.170 / 0.200 / 0.160 / 0.170 / 0.170 / 0.190
CaO / 10.9 / 10.9 / 9.84 / 8.13 / 9.28 / 10.7 / 10.4
Na2O / 3.55 / 2.44 / 3.18 / 3.87 / 3.01 / 2.97 / 2.72
K2O / 1.07 / 1.00 / 1.04 / 1.53 / 1.01 / 1.09 / 1.08
P2O5 / 0.596 / 0.373 / 0.435 / 0.636 / 0.340 / 0.550 / 0.548
SO2 / 0.052 / 0.106 / 0.012 / 0.025 / 0.012 / 0.032 / 0.012
LOI / <0.1 / 1.59 / 0.14 / 0.55 / <0.1 / 0.21 / <0.1
Σ / 99.4 / 99.0 / 98.6 / 98.8 / 99.0 / 99.1 / 99.2
FeO / 9.46 / 8.85 / 8.77 / 6.42 / 8.52 / 7.29 / 8.04
Mg# / 64.4 / 66.9 / 59.1 / 61.2 / 67.1 / 69.2 / 75.0
Cr / 390 / 396 / 209 / 95.0 / 393 / 511 / 733
Co / 56.7 / 59.7 / 65.0 / 40.0 / 54.4 / 57.0 / 60.0
Ni / 232 / 181 / 129 / 90.0 / 263 / 278 / 403
Rb / 31.5 / 28.0 / 27.0 / 36.0 / 28.0 / 27.8 / 25.1
Sr / 741 / 451 / 721 / 790 / 402 / 643 / 705
Zr / 236 / 193 / 196 / 304 / 151 / 248 / 237
Nb / 85.0 / 40.2 / 47.0 / 59.0 / 36.1 / 59.9 / 55.5
Sc / 25.2 / 33.3 / 27.0 / 27.7 / 30.0
V / 264 / 343 / 240 / 297 / 290
Y / 23.8 / 20.7 / 21.8 / 22.7 / 21.6
Cs / 0.308 / 0.750 / 0.540 / 0.447 / 0.874
Ba / 381 / 229 / 252 / 305 / 298
La / 45.9 / 25.7 / 21.6 / 35.2 / 34.8
Ce / 93.7 / 54.3 / 45.6 / 72.5 / 71.1
Pr / 9.96 / 6.65 / 5.68 / 8.77 / 8.48
Nd / 37.8 / 26.6 / 23.3 / 34.9 / 33.4
Sm / 7.19 / 5.54 / 5.20 / 7.28 / 6.77
Eu / 2.31 / 1.80 / 1.72 / 2.40 / 2.17
Gd / 6.89 / 5.51 / 5.37 / 7.08 / 6.45
Tb / 0.949 / 0.780 / 0.788 / 0.966 / 0.870
Dy / 4.97 / 4.24 / 4.38 / 4.97 / 4.52
Ho / 0.867 / 0.750 / 0.793 / 0.840 / 0.779
Er / 2.15 / 1.92 / 2.03 / 2.01 / 1.95
Tm / 0.274 / 0.250 / 0.272 / 0.253 / 0.246
Yb / 1.70 / 1.58 / 1.72 / 1.52 / 1.51
Lu / 0.232 / 0.220 / 0.241 / 0.207 / 0.206
Hf / 4.38 / 3.90 / 3.35 / 4.86 / 4.43
Ta / 3.50 / 2.01 / 1.78 / 2.97 / 2.74
Pb / 2.79 / 3.09 / 3.69 / 2.40 / 3.13
Th / 7.34 / 3.98 / 3.82 / 4.67 / 5.45
U / 1.91 / 1.09 / 0.953 / 1.23 / 1.65
Sample / NZ569 / NZ570A / NZ571 / NZ572 / NZ566 / NZ573 / NZ574 / NZ575
Region / NorthIsland
Unit / South Auckland Volcanic Field / KBI / Auckland Volcanic Field
Type / Basanite / Alkali Basalt / Basanite / Basanite / Alkali Basalt / Alkali Basalt / Basanite / Basanite
long / 174.9879 / 174.9892 / 174.998 / 174.9915 / 173.4804 / 174.7593 / 174.8475 / 174.744
lat / -37.2893 / -37.2412 / -37.2234 / -37.1702 / -35.2844 / -36.7848 / -36.8914 / -36.9679
Age / 0.82 - 0.77 Ma / 1.31 ± 0.12 Ma / ~ 1.31 Ma / 1.35 - 1.19 Ma / 0.05 - 0.06 Ma / 42 - 36 ka / 9.3 - 9 ka / 40 - 20 ka
Age ref. / F / F / F / F / G / H / H / I
SiO2 / 41.9 / 44.3 / 46.7 / 46.5 / 49.5 / 45.9 / 44.0 / 42.5
TiO2 / 3.20 / 2.57 / 2.46 / 2.6 / 1.67 / 2.28 / 2.55 / 2.82
Al2O3 / 12.2 / 13.2 / 14.2 / 14.7 / 17.0 / 13.0 / 12.2 / 12.1
Fe2O3t / 15.4 / 13.5 / 13.6 / 13.1 / 8.90 / 14.0 / 14.0 / 13.72
MgO / 10.5 / 9.95 / 7.45 / 7.33 / 6.98 / 10.3 / 10.6 / 11.88
MnO / 0.200 / 0.200 / 0.190 / 0.190 / 0.140 / 0.180 / 0.200 / 0.190
CaO / 9.80 / 9.26 / 7.95 / 8.48 / 10.8 / 9.60 / 10.47 / 10.6
Na2O / 3.91 / 2.88 / 4.38 / 4.17 / 3.08 / 3.06 / 3.8 / 3.95
K2O / 1.60 / 1.20 / 1.77 / 1.75 / 0.760 / 0.840 / 1.35 / 0.740
P2O5 / 0.821 / 0.568 / 0.731 / 0.544 / 0.272 / 0.388 / 0.72 / 0.613
SO2 / 0.086 / 0.023 / 0.012 / 0.046 / 0.012 / 0.012 / 0.057 / 0.045
LOI / <0.1 / 1.23 / <0.1 / <0.1 / <0.1 / <0.1 / <0.1 / <0.1
Σ / 99.7 / 98.8 / 99.7 / 99.5 / 99.3 / 99.7 / 100 / 99.2
FeO / 9.83 / 7.27 / 8.95 / 8.70 / 6.61 / 9.50 / 9.51 / 8.40
Mg# / 65.6 / 71.4 / 59.8 / 60.1 / 65.4 / 66.0 / 66.4 / 71.7
Cr / 300 / 401 / 236 / 226 / 232 / 377 / 294 / 424
Co / 64.2 / 55.9 / 52.0 / 44.0 / 36.5 / 62.0 / 60.0 / 62.1
Ni / 245 / 266 / 151 / 143 / 83.7 / 285 / 220 / 279
Rb / 22.4 / 21.1 / 28.0 / 25.0 / 10.2 / 12.9 / 29.0 / 23.4
Sr / 957 / 707 / 783 / 757 / 422 / 430 / 735 / 648
Zr / 338 / 323 / 334 / 334 / 146 / 180 / 234 / 252
Nb / 64.0 / 57.1 / 58.0 / 53.0 / 23.4 / 35.9 / 60.0 / 68.3
Sc / 21.8 / 24.8 / 33.4 / 26.9 / 25.6
V / 279 / 264 / 236 / 257 / 305
Y / 23.2 / 22.7 / 20.3 / 20.3 / 22.2
Cs / 0.227 / 0.285 / 0.185 / 0.168 / 0.337
Ba / 253 / 208 / 115 / 147 / 285
La / 47.4 / 35.2 / 13.9 / 21.7 / 40.3
Ce / 105 / 71.6 / 30.0 / 45.4 / 80.4
Pr / 12.0 / 8.35 / 3.77 / 5.60 / 9.45
Nd / 46.8 / 32.4 / 16.0 / 23.0 / 36.9
Sm / 9.21 / 6.46 / 3.84 / 5.12 / 7.29
Eu / 2.97 / 2.14 / 1.42 / 1.79 / 2.35
Gd / 8.38 / 6.24 / 4.18 / 5.31 / 6.91
Tb / 1.103 / 0.871 / 0.644 / 0.764 / 0.938
Dy / 5.39 / 4.65 / 3.80 / 4.19 / 4.83
Ho / 0.872 / 0.825 / 0.724 / 0.749 / 0.83
Er / 2.05 / 2.10 / 1.93 / 1.87 / 2.01
Tm / 0.243 / 0.279 / 0.272 / 0.245 / 0.252
Yb / 1.43 / 1.77 / 1.76 / 1.53 / 1.52
Lu / 0.188 / 0.243 / 0.252 / 0.211 / 0.208
Hf / 6.35 / 5.80 / 2.86 / 3.73 / 4.79
Ta / 3.27 / 3.02 / 1.189 / 1.78 / 3.39
Pb / 2.96 / 2.81 / 1.75 / 1.81 / 2.31
Th / 4.93 / 5.06 / 2.05 / 2.82 / 5.22
U / 1.88 / 1.74 / 0.633 / 0.644 / 1.51
Table 1 electronic supplementary material: Whole-rock major and trace element data, eruption ages, and WGS 84 coordinates. All oxides and LOI are given in wt.-%, trace element concentrations are given in ppm. KBI is “Kaikohe Bay of Island Volcanic Field”. Age references: A: Hoke et al. (2000); B: Mathews & Curtis (1966); C: Forsyth (2001); D: Coombs et al. (1986); E: Briggs (1986); F: Briggs et al. (1994); G: Smith et al. (1993); H: McDougal et al (1969); I: Heming and Barnet (1986); J: Sewell (1988).
References:
Briggs RM (1986) Volcanic Rocks of the Waikato region, western NorthIsland, and some possible petrologic and tectonic constraints on their origin. In: Smith IEM (ed.) Late Cenozoic Volcanism in New Zealand. The Royal Society of New Zealand Bulletin 23:76-91
Briggs RM, Okada T, Itaya T, Shibuya H, Smith IEM (1994) K-Ar Ages, Paleomagnetism, and geochemistry of the South Auckland Volcanic Field, North-Island, New-Zealand. New Zealand Journal of Geology and Geophysics 37(2):143-153
Coombs DS, Cas RA, Kawachi Y, Landis CA, McDonough WF, Reay A (1986) Cenozoic Volcanism in North, East and Central Otago. Royal Society of New Zealand Bulletin 73:278 - 312
Forsyth PJ (2001) Geology of the Waitaki area. In: Institute of Geological & Nuclear Sciences 1:250000 geological map 19, vol. Institute of Geological & Nuclear Sciences Ltd, Lower Hutt, New Zealand., p 1 sheet + 64p.
Heming RF, Barnet PR (1986) The petrology and petrochemistry of the Auckland Volcanic Field. In: Smith IEM (ed.) Late Cenozoic Volcanism in New Zealand. The Royal Society of New Zealand Bulletin 23, 64-75
Hoke L, Poreda R, Reay A, Weaver SD (2000) The subcontinental mantle beneath southern New Zealand, characterised by helium isotopes in intraplate basalts and gas-rich springs. Geochimica et Cosmochimica Acta 64(14):2489-2507
Mathews WH, Curtis GH (1966) Date of Pliocene-Pleistocene boundary in New Zealand. Nature 212(5066):979-980
McDougal I, Polach HA, Stipp JJ (1969) Excess radiogenic argon in young subaerial basalts from Auckland Volcanic Field, New Zealand. Geochimica et Cosmochimica Acta 33(12):1485-1520
Sewell RJ (1988) Late Miocene volcanic stratigraphy of Central Banks Peninsula, Canterbury, New Zealand. New Zealand Journal of Geology and Geophysics 31(1):41-64
Smith IEM, Okada T, Itaya T, Black PM (1993) Age relationships and tectonic implications of late Cenozoic basaltic volcanism in Northland, New-Zealand. New Zealand Journal of Geology and Geophysics 36(3):385-393