Bowen’s Reaction Series describes the temperatures at which different common silicate minerals change from the liquid to solid phase (or from the enterprise to liquid). In full general terms, the higher temperature minerals accept a higher proportion of atomic position out 26 in addition to magnesium, in addition to are thus considered to be mafic. The lower temperature minerals are related to the contrary terminate of the compositional spectrum (lower inward atomic position out 26 in addition to magnesium, higher in silicon in addition to oxygen), in addition to are considered to be felsic. Some minerals are clearly mafic, unopen to are clearly felsic, in addition to unopen to autumn inward betwixt these 2 extremes. Common mafic minerals include olivine, pyroxene, amphibole, biotite mica, in addition to the plagioclase feldspars. Common felsic minerals include quartz, muscovite mica, in addition to the orthoclase feldspars. Different magma compositions evidently effect inward dissimilar igneous rocks.
The other component which contributes to the differences in igneous rocks relates to the length of fourth dimension it took for the magma to crystallize. In full general terms, the faster the charge per unit of measurement of cooling (common to extrusive, volcanic rocks), the smaller the resulting mineral grains. Slower cooling histories (commonly intrusive) effect inward a coarser-grained rock.
Mafic igneous rocks (olivine, pyroxene, in addition to the plagioclase feldspars) include basalt (extrusive) in addition to gabbro (intrusive), acre felsic igneous rocks (quartz, amphibole, mica, in addition to the orthoclase feldspars) include granite (intrusive) in addition to rhyolite (extrusive). Magmas of intermediate composition effect inward the crystallization of intermediate minerals (actually a mix of the mid-range minerals: amphibole in addition to both types of feldspar), amongst the mutual igneous rocks existence andesite (extrusive) in addition to diorite (intrusive).