Eruption of high silica rhyolites - Textural Analysis

高硅流纹岩的喷发 - 结构分析

• 批准号: 602-2009
• 负责人: Fowler, Anthony
• 金额: $ 1.46万
• 依托单位: University of Ottawa
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=496879
• 关键词: Eruption; silica; rhyolites; Textural; Analysis

Volcanic rocks are formed from magma produced at depths of many 10's of km. The magma is often extremely viscous and gas-rich. The way in which the gas separates and escapes from very viscous magma controls whether eruption is effusive or explosive, in like manner to the way which gas can be un-mixed from the liquid upon opening a champagne bottle. Viscous magmas cool during their ascent producing a variety of minerals such as quartz and feldspar. Just as Canadians know first hand, and recognize the variety of different crystalline forms that fall as ice from clouds, we know that the minerals of these volcanic systems form different patterns depending upon their conditions of formation. By examination of these mineral patterns we are able to infer some information about the nature of deep processes that led to eruption.

火山岩是由数十公里深处产生的岩浆形成的。岩浆通常非常粘稠，富含气体。气体从非常粘稠的岩浆中分离和逸出的方式控制着喷发是喷涌式的还是爆炸式的，就像打开香槟酒瓶时气体从液体中分离出来的方式一样。粘性岩浆在上升过程中冷却，产生各种矿物，如石英和长石。正如加拿大人所知道的第一手资料，并认识到各种不同的晶体形式，从云中落下的冰，我们知道，这些火山系统的矿物形成不同的模式，这取决于它们的形成条件。通过对这些矿物模式的研究，我们能够推断出一些关于导致火山爆发的深层过程的性质的信息。