The Life History of an Arc Volcano: Insights from a Collaborative Petrologic, Paleomagnetic, and Geochronologic Study

弧火山的生命史：岩石学、古地磁和地质年代学合作研究的见解

• 批准号: 9019441
• 负责人: Michael Dungan
• 金额: $ 28.93万
• 依托单位: Southern Methodist University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-11-01 至 1995-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9019441&HistoricalAwards=false
• 关键词: Life; History; Arc; Volcano; Insights

The Quaternary Southern Volcanic Zone (SVZ) of the Chilean Andes has been investigated by teams of US scientists concerned with quantifying the mantle source components in arc parent magmas, and the degree to which these magmas have interacted with arc crust. Longitudinal variations in crustal age, thickness, and the age of the subducted plate make this an ideal target for regional studies. The primary focus of this project is an exceptionally detailed and comprehensive investigation of Tatara-San Pedro (TSP) (36o S), the youngest edifice (ca. 150ka to Holocene) of the San Pedro-Pellado volcanic complex. This study will be grounded on a wealth of regional information concerning along-strike and across strike variations in Quaternary activity. In addition to its compositional variability, TSP is exceptionally well exposed from its base: 1 km vertical (or composite) sections (up to 150 flows) are exposed in deep glacial canyons from all quadrants of the cone. These sections will be sampled on a 100% flow-by-flow basis (chemistry and paleomagnetism) in conjunction with sampling of abundant crustal xenoliths, lateral sampling of select Pleistocene lavas, and detailed surface sampling of two spectacularly heterogeneous Holocene flows. A detailed reconstruction of the eruptive history of TSP will be made by correlating among these sections through integration of paleosecular magnetic variation data, physical stratigraphy, geochemistry and petrography, and high-resolution geochronology.

美国科学家团队对智利安第斯山脉的第四纪南部火山区（SVZ）进行了调查，这些小组关心的是量化弧父岩浆中的地幔源组件，以及这些岩浆与弧形壳相互作用的程度。 地壳年龄，厚度和俯冲板年龄的纵向变化使这是区域研究的理想目标。 该项目的主要重点是对塔塔拉 - 山·佩德罗（TSP）（TSP）（36o s）的一项非常详细，全面的研究，这是圣佩德罗 - 佩拉拉多火山综合体的最年轻的大厦（约150ka至Holcene）。 这项研究将基于大量有关沿着撞击和跨第四纪活动的罢工变化的区域信息。 除了其组成变异性外，TSP还与其底部相处得很好：垂直（或复合）部分（或复合）部分（最高150个流）在锥体所有象限的深冰川峡谷中暴露在外。 这些部分将以100％的流量基础（化学和古磁性）为100％进行采样，并结合采样丰富的地壳异甲岩，精选的更新世熔岩的侧面采样，并详细的表面取样了两种壮观的异构全趋化全趋化性全循环。 通过整合古分类磁变化数据，物理地层，地球化学和岩石学以及高分辨率的基量学，将通过在这些部分之间关联TSP的详细重建TSP的详细重建。