tephra SiO2 TiO2 Al2O3 FeO MnO MgO CaO Na2O K2O total Ref L3574 Tephra 73.52 0.08 12.29 1.62 0.03 0.08 1.32 4.08 2.73 95.76 1207 L3574 Tephra 67.72 0.54 15.49 5.96 0.17 0.59 3.32 4.26 1.86 99.92 1207 L3574 Tephra 67.13 0.41 15.23 5.35 0.25 0.56 3.13 4.41 2.15 98.62 1207 L3574 Tephra 67.07 0.56 15.18 5.55 0.14 0.60 3.37 4.15 2.02 98.63 1207 L3574 Tephra 66.64 0.47 15.09 5.79 0.19 0.43 3.32 4.04 2.07 98.03 1207 L3574 Tephra 66.52 0.48 15.25 5.59 0.17 0.54 3.15 3.86 1.95 97.52 1207 L3574 Tephra 64.68 0.48 14.90 5.68 0.18 0.52 3.29 4.15 2.01 95.90 1207 L3574 Tephra 56.30 2.15 13.18 12.08 0.36 3.26 6.36 3.85 1.38 98.91 1207 ------------------------------------------------------------------------ 1207: Dugmore, A.J. and Newton, A.J. (1997) Holocene tephra layers in the Faroe Islands. Frodskaparrit 45, 141-154..