Final answer:
Bowen's Reaction Series is a framework that explains how minerals in igneous rocks crystallize or melt based on their melting temperatures, with mafic minerals like olivine and pyroxene crystallizing at the highest temperatures, and felsic minerals like quartz and feldspar crystallizing at lower temperatures.
Step-by-step explanation:
Bowen's Reaction Series describes the pattern of mineral crystallization and melting in igneous rocks. It illustrates how minerals crystallize from magma in a systematic fashion based on their melting points; minerals that crystallize at higher temperatures are referred to as 'mafic' (magnesium and iron-rich) and those that crystallize at lower temperatures are called 'felsic' (feldspar and silica-rich).
According to this series, the first minerals to crystallize from a cooling magma are mafic minerals like olivine and pyroxene, which form at the highest temperatures. Felsic minerals such as quartz and feldspar crystallize at lower temperatures. Identifying the sequence of mineral formation helps geologists deduce the cooling history of the igneous rocks, as well as the relative contributions of different minerals to rock composition. This is important in classifying rocks as mafic, intermediate, felsic, or ultramafic.
When minerals are too small to see in an extrusive igneous rock, geologists can use the rock's color as a diagnostic tool to identify its mineral content, thanks to the varying concentrations of darker mafic and lighter-colored felsic minerals.