NORRRM: A Free Software to Calculate the CIPW Norm

This work gives an

introduction to the R package NORRRM whose main purpose is to calculate the

CIPW Norm. Although there are many softwares and spreadsheets available to

estimate the standard mineral assemblages in igneous rocks, this package has

the following advantages: a) it has the ability to be run on any operating

computer systems (BSD, GNU/Linux, Mac OS X®, Windows®);

b) an input argument allows choose different procedures to set the Fe-oxidation

ratio; c) the options to use whole-rock major as well as minor oxides and trace

elements in the computation; d) the output data yields highly consistent

results achieving absolute match between the sum of the input weights of oxides

recalculated on an anhydrous basis and the sum of the weights of estimated

normative minerals and; e) the functions are written in R language and released

under terms that guarantee users the freedom to study, adapt, modify, and

distribute the software.