Volatiles in Submarine Magmas: An Experimental Study

该项目的目的是为了解海底玄武岩岩浆中挥发分的行为提供实验基础。首席调查员将测量(1)二氧化碳在大洋中脊玄武岩成分、温度和压力范围内的溶解度；(2)水在相同参数范围内的溶解度，并确定水的溶解度对二氧化碳溶解度的影响；(3)气泡成核和生长的动力学。在这些实验中，将测定Fe2+/Fe3+的比值，以揭示脱气对岩浆氧化状态的影响。%岩浆挥发物控制着火山喷发的风格。这个项目中将要进行的实验将提供有关两种关键挥发物--水和二氧化碳--在岩浆中的溶解度的基本数据。这些数据将有助于理解岩浆在上升和喷发时如何脱气，并确定在气泡生长过程中挥发性物质之间是否发生了动力学分馏。

The objective of this project is to develop an experimental basis for understanding the behavior of volatiles in submarine basaltic magmas. The principal investigators will measure (1) solubility of carbon dioxide over a range of mid-ocean ridge basalt compositions, temperatures and pressures; (2) solubility of water over the same parameter range and determine the effect of water solubility on that of carbon dioxide; (3) kinetics of bubble nucleation and growth. During these experiments, the Fe2+/Fe3+ ratio will be determined in order to unravel the effects of degassing on oxidation state of the magmas. %%% Magmatic volatiles control the style of volcanic eruptions. Experiments such as the ones to be carried out in this project will provide fundamental data on the solubility of two critical volatiles in magmas, water and carbon dioxide. These data will help to understand how magmas degas as they ascend and erupt and to determine if kinetic fractionation among volatile species occur during bubble growth.