Heather Douglas
Weighing complex evidence in a democratic society
Kennedy Institute of Ethics journal
deepseated conviction paul gast trace element approach least powerful experimental petrology solve major petrological problems paper review present status utilization trace elements igneous processes acknowledges opinion study historical development trace element geochemistry includes brief discussion analytical methods presently available review various models describe trace element behavior added concern mixing processes set graphical notations proposed extended model partition coefficients methods analytical determinations effective dependence temperature pressure composition considered discuss various methods recognition process responsible variation trace element concentrations suite rocks process identification achieved approach inverse problems allows determination characteristic parameters process detail approach exemplified fractional crystallization process applied series alkali basalts terceira island conclude solution inverse problems determinations partition coefficients based ion probe data might future development trace element geochemistry