橄榄石形成晶体,然后它与其余的岩浆发生反应,因为辉石形成了它的代价。在某一点上,所有的橄榄石都被吸收,只有辉石存在。不连续的系列开始于橄榄石,然后是辉石,角闪石和黑云母。使其成为“反应系列”而不是普通系列的原因是,当熔体冷却时,系列中的每种矿物质都被下一种矿物质取代。正如鲍文所说,“矿物质按照它们出现的顺序消失……是反应系列的本质。”然后辉石与液体反应,因为闪石晶体取代它,然后黑云母取代闪石。连续系列是斜长石长石。在高温下,形成高钙品种的钙长石。然后随着温度的降低,它被更多富含钠的品种所取代:bytownite,labradorite,andesine,oligoclase和albite。随着温度的持续下降,这两个系列合并,更多的矿物质按此顺序结晶:碱性长石,白云母和石英。次要反应系列涉及尖晶石类矿物:铬铁矿,磁铁矿,钛铁矿和钛铁矿。鲍文把它们放在两个主要系列之间。 Bowen反应系列描述了岩浆矿物质在冷却时如何变化。鲍文计算了两组这些,他在1922年的论文“石油发生中的反应原理”中将其命名为不连续和连续系列。岩石学家诺曼·鲍文(Norman Bowen,1887-1956)在20世纪初进行了数十年的熔化实验,以支持他的花岗岩理论。他发现,随着玄武岩熔体的缓慢冷却,矿物质以一定的顺序形成晶体。

美国范德堡大学地质学Essay代写: 鲍文的反应系列

Olivine forms crystals, then it reacts with the rest of the magma as pyroxene forms at its expense. At a certain point, all the olivine is resorbed and only pyroxene exists.The discontinuous series starts with olivine, then pyroxene, amphibole, and biotite. What makes this a “reaction series” rather than an ordinary series is that each mineral in the series is replaced by the next one as the melt cools. As Bowen put it, “The disappearance of minerals in the order in which they appear … is of the very essence of the reaction series.” Then pyroxene reacts with the liquid as amphibole crystals replace it, and then biotite replaces amphibole. The continuous series is plagioclase feldspar. At high temperatures, the high-calcium variety anorthite forms. Then as temperatures fall it is replaced by more sodium-rich varieties: bytownite, labradorite, andesine, oligoclase, and albite. As the temperature continues to fall, these two series merge and more minerals crystallize in this order: Alkali feldspar, muscovite, and quartz. A minor reaction series involves the spinel group of minerals: chromite, magnetite, ilmenite, and titanite. Bowen placed them between the two main series. The Bowen reaction series is a description of how magma’s minerals change as they cool. Bowen worked out two sets of these, which he named the discontinuous and continuous series in his 1922 paper “The Reaction Principle in Petrogenesis.” The petrologist Norman Bowen (1887-1956) carried out decades of melting experiments in the early 1900s in support of his theory of granite. He found that as a basaltic melt slowly cooled, minerals formed crystals in a definite order.

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