PearceEtAl {GCDkit} | R Documentation |
Assigns data for the MgO-FeOt-Al2O3 triangle proposed by
Pearce et al.(1977) into Figaro template (list 'sheet
') and
appropriate values into 'x.data
' and 'y.data
'.
PearceEtAl()
Triangular diagram with apices MgO, FeOt and Al2O3, proposed by Pearce et al.(1977). The boundaries were defined solely for subalkaline volcanic rocks with SiO2 between 51-56 wt %. Following geotectonic positions may be identified using the diagram:
Spreading Center Island (or inter-plate island) - oceanic islands adjacent to ocean-ridge spreading,
such as Iceland or Galapagos; the authors 'do not consider this field well established'.
Orogenic
Ocean Ridge and Floor
Ocean Island
Continental
sheet |
list with Figaro Style Sheet data |
x.data, y.data |
MgO, FeOt and Al2O3 in wt. % recalculated to two dimensions |
Vojtěch Janoušek, vojtech.janousek@geology.cz
Pearce TH, Gorman BE & Birkett TC (1977) The relationship between major element geochemistry and tectonic environment of basic and intermediate volcanic rocks. Earth Planet Sci Lett 36: 121-132. doi: 10.1016/0012-821X(77)90193-5
data(atacazo) accessVar("atacazo") # Plot the diagram plotDiagram("PearceEtAl",FALSE)