Bowens Reaction Series Sire Kassama 2014 Intro to

Bowen’s Reaction Series Sire Kassama 2014

Intro to Info • Mafic: Iron and Magnesium rich; dark colored; gabbro; basalt • Felsic (or sialic): rich in Aluminum and Silicon Dioxide; light colored; granite; rhyolite; has minerals such as quartz and KAl. Si 3 O 8 (Potassium Feldspar) • Intermediate: light and dark minerals; diorite; andesite • Felsic to Intermediate rocks and minerals are more viscous which cause gas to be trapped

Bowen’s Reaction Serires: • Olivine is the first mineral to crystallize from the very high temperatures as magma first starts to cool. • Quartz is the last mineral to form from the last remaining melt of high silica content. • Bowen’s reaction series indicates that minerals with the highest melting temperatures crystallize from a cooling magma before those with lower melting points. • Bowen’s reaction series does not explain the origin of magmas. • Bowen’s reaction series indicates that ferromagnesian minerals in magma crystallize in the sequence shown in the discontinuous branch.

Need To Know • Bowen’s reaction series offers an explanation for the differentiation of silicic and mafic minerals in magma. • Biotite is the most stable of minerals in the discontinuous reaction series. • Ionic bonding occurs at the highest temperatures within the discontinuous branch • The discontinuous reaction series follows a repetitive sequence of stable to unstable pattern not permitting simultaneous formation of similar minerals • The continuous reaction series follows a gradual transitional pattern of mineral formation thus permitting combinations of minerals to form and exist as the magma cools.

Need To Know • Which list the sequence of ferromagnesian silicate minerals crystallizing from a cooling magma? olivine, pyroxene, amphibole, biotite • Basalt is most likely to contain calcium-rich feldspar. • Bowen’s Reaction Series illustrates the relationship between: chemical composition, temperature and mineral structure

• Compared to felsic igneous rocks, mafic igneous rocks contain greater amounts of 1. white quartz 2. aluminum 3. pink feldspar 4. iron

• Of the following paired minerals, which are characteristic of lower crystallization temperatures and absent in basalt and gabbro? a. pyroxene and olivine c. biotite and olivine b. quartz and pyroxene d. quartz and muscovite

Bowen’s Reaction Series Chart

Other Resources • The following questions and answers are from the New York State Regents Website: http: //www. regentsprep. org/Regents/core/ques tions/topics. cfm? Course=ESCI • Geology. com