Bulk rock data for the central-eastern Aleutian volcanoes

We present major and trace element data for 82 rock samples from central-eastern Aleutian volcanoes. Most samples were collected during joint GeoPRISMS-DCO-AVO field campaigns in 2015 and 2016 (PIs: Roman, Plank, Hauri). The samples were crushed in plastic ziploc bags using a hammer, cleaned with deionized water, and 1-10 mm fragments were powdered in a alumina-ceramic ball mill. Rock digestion followed the procedure of Kelley et al. (2003). Trace element analyses were conducted by ICP-MS using a PQ ExCell at Lamont-Doherty Earth Observatory (LDEO) following the methods of Wade et al. (2005). Major element analyses were conducted using an Agilent 700-series ICP-ES at LDEO following the methods of Wade et al. (2005). SiO2 is calculated by difference. LOI data were not collected for 26 samples. In those cases, a value of 1 wt% was assumed. The objectives of the work are to understand magmatic processes and characterize along-arc geochemical trends in the Aleutians. Melt inclusion and host olivine data from these samples samples are also published in Earthchem. A report that includes more information on the samples presented here can be found online: Plank, T., Rasmussen, D., Stelling, P., Roman, D. 2020. Field Report for the Collection of Mafic Tephra from the Aleutians Islands between Unimak and the Island of Four Mountains (Alaska, USA), Version 1.0. Interdisciplinary Earth Data Alliance (IEDA).

本数据集提供了阿留申群岛中东部火山的82件岩石样品的主量元素（major element）与微量元素（trace element）数据。多数样品采集于2015至2016年联合开展的GeoPRISMS-DCO-AVO野外科考项目（项目负责人：Roman、Plank、Hauri）。样品先以铁锤在塑料自封袋中破碎，经去离子水清洗后，选取1~10 mm的碎屑在氧化铝陶瓷球磨机中磨制粉末。岩石消解流程参照Kelley等人（2003）的方法。微量元素分析采用电感耦合等离子体质谱仪（ICP-MS）PQ ExCell，于拉蒙特-多尔蒂地球观测站（Lamont-Doherty Earth Observatory, LDEO）完成，分析流程参照Wade等人（2005）的方法。主量元素分析采用安捷伦700系列电感耦合等离子体发射光谱仪（ICP-ES），于LDEO完成，分析流程同样参照Wade等人（2005）的方法。二氧化硅（SiO₂）含量通过差减法计算得到。26件样品未获取烧失量（Loss on Ignition, LOI）数据，此类样品的烧失量默认赋值为1 wt%。本研究的目标为厘清阿留申群岛的岩浆作用过程，并刻画弧带内沿走向的地球化学变化特征。本次研究涉及的熔体包裹体及寄主橄榄石数据亦发表于Earthchem数据库。关于本次展示样品的详细信息可查阅以下在线报告：Plank T、Rasmussen D、Stelling P、Roman D. 2020. 《阿留申群岛乌尼马克岛与四山群岛之间基性火山碎屑采集野外报告》（美国阿拉斯加），版本1.0. 跨学科地球数据联盟（Interdisciplinary Earth Data Alliance, IEDA）