Acquisition of a Multi-Anvil Press

EAR-0444067 JenkinsEAR-0444067 Jenkins这项提议是为了获得一台多砧压机，主要目的是研究与超高压变质作用相关的矿物学反应和矿物成分变化。已经确定了几个项目，这些项目将成为最初的研究重点。首先，将检查蓝闪石的上压稳定性，将其分解为滑石和翡翠，以试图解决这一边界位置上现有的差异。这一反应边界确定了蓝片岩变质相的压力上限，并可能在压力上对应于超高压变质作用的开始(由柯石英的存在来定义)。其次，将研究CaO-MgO-Al_2O_3-SiO_2-H_2O体系中低压力组合橄榄石+富透辉石单斜辉石转化为高压组合劳钠石+富粗粒石榴石的单变量反应，以更好地了解含钙闪石榴辉岩的形成压力。第三，研究了在上述体系中加入铁后，含榴辉岩的稳定域可能扩大的情况，即6榴辉石=4粗粒榴辉岩+5蓝晶石+柯石英+3H2O。后两个项目将有助于划定UPH地体榴辉岩中榴辉石(或绿帘石)的稳定范围。这种矿物可能是将水返回地球地幔的重要宿主。这项建议中要求的多砧压机将支持与超高压变质作用相关的许多其他项目的研究。这一提议的更广泛影响是(1)通过允许在以前无法达到的压力和温度下进行研究，改善了该机构的研究基础设施；(2)通过为本科生和研究生提供开展与行星内部相关的研究的机会。

EAR-0444067JenkinsThis proposal is for the acquisition of a multi-anvil press for the primary purpose of studying mineralogical reactions and mineral-composition variations relevant to ultra-high-pressure (UHP) metamorphism. Several projects have been identified that will be the initial focus of research. First, the upper-pressure stability of glaucophane, which breaks down to talc and jadeite, will be examined to try to resolve existing discrepancies in the location of this boundary. This reaction boundary defines the upper-pressure limit of the blueschist metamorphic facies and may correspond in pressure to the onset of UHP metamorphism (defined by the presence of coesite). Second, univariant reactions defining the conversion of the low-pressure assemblage zoisite + diopside-rich clinopyroxene to the high-pressure assemblage lawsonite + grossular-rich garnet in the system CaO-MgO-Al2O3-SiO2-H2O will be investigated to better understand the pressures at which lawsonite-bearing eclogites occur. Third, the possible expansion of the stability field of zoisite-bearing eclogites, limited by the reaction 6 zoisite = 4 grossular + 5 kyanite + coesite + 3 H2O, resulting from the addition of ferric iron to the above system will be examined. The latter two projects will help delimit the stability field of zoisite (or epidote) in eclogites from UPH terranes. This mineral may be an important host for returning water to Earth's mantle. The multi-anvil press requested in this proposal will support research on many other projects relevant to UHP metamorphism. The broader impacts of this proposal are (1) improving the research infrastructure at this institution by allowing research at pressures and temperatures that were not previously attainable and (2) by providing undergraduate and graduate students opportunities to conduct research relevant to planetary interiors.