RUI: Halogens in Granitic Systems

9902185沃尔夫氟是一种次要但重要的气体，从许多火山喷出。 它的排放表明，火山内的熔融岩石或岩浆含有氟，但正在慢慢失去氟。 我们必须了解火山系统中的氟，因为这种元素在岩浆中的存在会影响各种基本参数，如岩浆的粘度、密度和聚合作用;其他元素在岩浆中结合和扩散的能力;许多矿物结晶或熔融的条件;以及其它元素在共存的晶相、液相和气相之间的分布。 这些知识在确定氟在与花岗岩有关的岩浆热液矿床形成过程中作为助熔剂和矿化剂的能力方面具有重要价值，如果我们更多地了解氟对矿床的影响，那么我们就可以利用这些信息来帮助我们找到未来的矿床。 然而，这种乐观的设想有一个问题，那就是我们需要知道岩浆中的氟含量，但是如果大部分氟在岩浆凝固成岩石之前就从结晶岩浆中流失了，我们怎么能知道呢？ 我们可以这样做，因为某些矿物在岩浆中生长，将氟结合到它们的结构中，并且随后不会失去它。通过测量这些矿物的氟含量，我们可以确定这些矿物生长的岩浆中的氟含量。 然而，我们只有知道这些矿物相对于共存岩浆中的氟量“吸走”了多少氟（这个参数称为分配系数或分配系数），才能做到这一点，而且我们只能通过做实验来确定这个参数。 因此，在一系列高压和高温实验中，我们将模拟火山下的条件，从一系列岩浆成分中生长出各种不同的含氟矿物，以确定共存相中的氟含量，相应的分配系数，以及当应用于真实的岩石时，有多少氟最初在岩浆中，又有多少流失了。

9902185 Wolf Fluorine is a minor yet important gas emitted from many volcanoes. Its emission indicates that the molten rock, or magma, within the volcano contains but is slowly losing its fluorine. It is important for us to learn about fluorine in volcanic systems because the presence of this element in magmas affects a wide variety of fundamental parameters such as the viscosity, density and polymerization of the magma; the ability of other elements to bond within and diffuse through the magma; the conditions under which many minerals crystallize or melt; and the distribution of other elements between coexisting crystal, liquid and gas phases. Such knowledge is of great value in determining the ability of fluorine to act as a flux and mineralizer during the formation of granite-associated magmatic-hydrothermal ore deposits if we know more about the effects of fluorine on ore deposition, then we just may be able to use this information to help us find future ore deposits. One problem with this optimistic scenario, however, is that we need to know the fluorine content of the magma, but how can we do so if most of the fluorine was lost from the crystallizing magma before it solidified into rock? We can do so because certain minerals that grow in the magma incorporate fluorine into their structures and do not subsequently lose it. By measuring the fluorine content of these minerals, we may be able to determine the fluorine content of the magma from which these minerals grew. However, we can only do so if we know how much fluorine these minerals "sucked up" relative to the amount of fluorine in the coexisting magma (this parameter is called the distribution or partition coefficient), and we can only determine this parameter by doing experiments. Thus, in a series of high pressure and high temperature experiments simulating conditions beneath volcanoes, we will grow a variety of different fluorine-bearing minerals from a range of magma compositions to determine the fluorine contents in the coexisting phases, the corresponding distribution coefficients, and, when applied to real rocks, how much fluorine was in the magma initially and how much was lost.