Table 2.

Major and trace elements of the tuffs in the Pingdingshan section

CH-ash-2CH-ash-3CH-ash-4CH-ash-5CH-ash-6CH-ash-7CH-ash-8CH-ash-9CH-ash-10CH-3PDS-5
SiO251.6749.7146.8454.5153.3853.448.1953.0448.9654.9153.98
TiO20.1830.1560.2680.3060.2090.1720.2060.1910.1260.410.408
Al2O333.2634.2937.4230.2931.830.9236.2630.8334.0227.2626.54
Fe2O3−0.260.640.370.150.130.490.81.47−0.131.071.78
MnO−0.004−0.005−0.004−0.004−0.005−0.002−0.005−0.0060.0020.0530.075
MgO1.771.290.651.321.291.520.851.471.191.541.53
CaO0.550.750.6110.870.760.440.570.420.250.22
Na2O0.060.040.110.10.140.120.150.110.180.230.22
K2O1.561.210.821.010.951.050.811.142.193.313.19
P2O50.0520.0670.0980.0950.1460.1120.0660.1450.4710.40.315
LOI11.0712.7213.1510.4311.1110.8513.1111.2812.679.811.05
Total99.91100.87100.3399.2100.0399.39100.88100.24100.199.2399.31
K2O+Na2O1.621.250.931.111.091.170.961.252.373.543.41
Al2O3/TiO2181.75219.81139.6398.99152.15179.77176.02161.41270.0066.4965.05
Ti1063.1876.41462.31702.71132.5956.51134.91057.5792.52338.72290.4
V1784.91853.41731.42014.61421.12325.71431.41262.3252.9216.7339.6
Ga38.227.415.923.817.515.310.412.214.724.122.1
Rb88.5112.574.278.272.165.136.150.286.0119.6113.4
Sr136.2152.9298.0277.4482.0364.0156.9474.6783.1488.3360.5
Y12.011.620.013.013.275.88.813.929.258.357.1
Zr105.085.1103.5128.6101.6107.877.9140.9152.3213.3268.6
Nb4.04.13.910.05.04.02.55.59.721.015.4
Mo0.61.81.41.51.21.12.83.29.945.641.3
Ba49.369.073.368.876.780.162.3107.4235.1474.9362.6
La13.625.938.139.358.547.45.233.630.9142.0112.5
Ce28.559.174.081.0115.893.010.366.154.6233.6182.6
Pr3.46.29.78.712.610.31.57.05.720.019.4
Nd12.621.739.331.345.735.37.125.920.895.072.8
Sm2.43.58.95.78.65.42.25.84.317.813.2
Eu0.30.41.20.81.10.70.40.80.72.21.6
Gd1.92.35.74.25.95.41.84.45.113.510.6
Tb0.30.30.80.60.81.20.30.71.12.01.8
Dy1.61.83.62.52.98.91.62.96.210.710.2
Ho0.40.40.70.50.52.40.30.51.22.42.3
Er1.21.32.01.41.57.20.91.53.16.76.6
Tm0.20.20.30.20.21.00.10.20.40.90.8
Yb1.11.11.61.31.15.90.81.22.74.84.7
Lu0.20.20.30.20.21.00.10.20.50.80.8
Hf9.25.43.55.75.85.63.75.67.18.810.3
Ta1.91.40.43.61.41.90.31.92.43.92.9
Pb18.728.926.027.433.920.611.338.991.3107.584.3
Th16.819.27.315.724.127.11.721.332.847.843.2
U4.34.65.66.85.58.34.17.010.526.622.4
∑REE79.9136.1206.3190.6268.6300.941.5164.6166.5610.5497.1
δEu0.50.40.50.50.50.40.60.50.50.40.4
δCe1.01.10.91.11.01.00.91.01.01.10.9
Ti/Th63.245.8199.9108.846.935.2651.749.624.148.953.0
Nb/Ta2.13.09.02.83.42.27.92.94.05.45.3

∑REE, total rare earth elements; LOI, loss on ignition; δEu = EuN/(SmN×GdN)1/2, δCe = CeN/(LaN×PrN)1/2, where subscript N denotes chondrite-normalized. Normalization values are after Sun & McDonough (1989).