Collaborative Research: Temporal and Spatial Geochemical Variations Across the Kamchatka Arc: An Evaluation of Mantle and Crustal Contributions to Arc Magmatism

9418176 Davidson我们建议在勘察加半岛的火山弧上进行两次地质和地球化学横断面。 这些样带位于不同的基底隆起上，尽管两者基本上都是海洋性的。 比较某一地点不同年代的火山岩，将使我们能够研究岩浆成分随时间的变化。 断面之间的比较将允许限制岩石圈修改（污染等）的影响。 通过沿着趋势进行比较，可以评价与俯冲有关的影响。 沿沿着每个断面到贝尼奥夫区的不同深度可能导致板状衍生组分的性质和量的变化，以及伴随的部分熔融程度的差异。 该地区火山岩中存在非常原始的熔岩和地幔捕虏体，这将有助于我们更好地了解源区成分和过程。 这项研究将大大提高我们对堪察加岛弧的岩浆活动和构造的认识，以及对与俯冲有关的岩浆活动的认识。

9418176 Davidson We propose to carry out two geological and geochemical transects across the volcanic arc of the Kamchatkan Peninsula. The transects are located on different basement terranes, although both are of largely oceanic affinity. Comparison of volcanic rocks of different ages at a given location will permit us to study changes in the compositions of magmas through time. Comparison between the transects will allow is to constrain the effects of lithospheric modification (contamination, etc.). Comparison along the trends will allow evaluation of subduction-related effects. The variable depth to the Benioff zone along each transect may result in variations in the nature and amount of the slab-derived component, and concomitant differences in the degree of partial melting. The occurrence of very primitive lavas and mantle xenoliths among the volcanic rocks of the region will help us to better understand source compositions and processes. This study will significantly advance our understanding of the magmatism and tectonics of the Kamchatkan arc, and of subduction-related magmatism in general.