PYROCLASTIC ERUPTIONS OF MOUNT ST. HELENS ON MAY 18, 1980

圣海伦斯火山于1980年5月18日喷发的火山碎屑沉积物是博士生C. W. Criswell过去几年来深入研究的课题。在美国地质勘探局和其他学术研究人员的合作下，他和PI绘制了三维地层和相网，并将其与六个喷发阶段进行了对比，并按时间间隔进行了定义。化学和地震数据表明，两种岩浆类型（白色和灰色）从一个7公里深的带状岩浆房中喷发出来，这些喷发物质的变化与喷发机制的变化有关，以及喷发前岩浆房内岩浆成分的空间差异。”该奖项将使Criswell能够继续这些研究，这些研究可能对预测圣海伦火山和类似火山的未来喷发具有重要意义。

The pyroclastic deposits erupted by Mt. St. Helens on May 18, 1980 have been the subject0of intensive study by C. W. Criswell, a PhD student, for the last several years. With the cooperation of the USGS and other academic researchers, he and the PI have mapped a three-dimensional stratigraphic and facies network and correlated it with six eruptive phases, defined by time interval. Chemical and seismic data suggest that two magma types (white and gray) erupted from a zoned magma chamber seven km. deep, and that these changes in the eruptive materials relate to changes in the mechanism of eruption, as well as spatial differences in the magma composition within the chamber prior to eruption." This award will enable Criswell to continue these studies which could have important imlications for predicting future eruptions at Mt. St. Helens and similar volcanoes.