Table 3.

Selected electron microprobe analyses for plagioclase found in recent lavas and tephra of the 2002–2003 Stromboli eruption

TypeRecent lavasScoriasPumices
SampleSt53St53St55St55St61St61St59St59St59St59St62St62St62St62St64St64
Sitecorerimcorerimcorerimcorerimcorerimcorerimcorerimcorerim
Analysis no.12345678910111213141516
DateDecember 2002December 2002January 2003January 2003February 2003February 2003December 2002December 2002December 2002December 2002April 2003April 2003April 2003April 2003April 2003April 2003
SiO246.250.047.950.348.250.548.450.946.250.547.550.646.550.350.145.2
Al2O332.630.431.430.131.430.131.229.434.030.232.230.232.630.330.233.2
FeOT0.830.911.020.900.950.570.990.890.870.871.040.840.940.740.990.67
CaO17.315.016.314.315.814.516.413.718.514.216.714.517.614.515.218.4
Na2O1.943.122.393.372.583.172.533.721.603.422.123.451.813.513.011.36
K2O0.200.370.320.540.320.640.420.710.260.590.230.57n.d.0.580.460.00
Total99.099.899.399.699.299.5100.099.2101.499.799.8100.299.499.999.998.8
Ab0.170.270.210.290.220.270.210.320.130.290.180.290.160.300.260.12
An0.820.710.780.680.760.690.760.640.850.670.800.680.840.670.720.88
Or0.010.020.020.030.020.040.020.040.010.030.010.030.030.03
  • T=Total iron as FeO; n.d.=not detected.