Iceland Geodynamics: Magma-Tectonic Interactions in South Iceland

冰岛地球动力学：冰岛南部的岩浆-构造相互作用

• 批准号: 0711456
• 负责人: Peter LaFemina
• 金额: $ 18.18万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0711456&HistoricalAwards=false
• 关键词: Iceland; Geodynamics; Magma; Tectonic; Interactions

Short-term (less than about one million years) extensional processes in the world's mid-ocean ridge system are a challenge to observe and quantify due to their subaqueous setting. Magmatic segmentation of ridges leads to along strike variations in accommodating mechanisms (e.g., fault displacements may increase toward the end of magmatic segments, where there is little magma available to accommodate extension via dike intrusion), further complicating strain signals. The goal of this research is to study the complex four-dimensional crustal deformation field associated with the divergent plate boundary zone of Iceland using dense wide-aperture survey GPS and high-rate continuous GPS networks, much like the EarthScope Plate Boundary Observatory network, and builds on a six-year collaboration between the Pennsylvania State University, the University of Miami, the Nordic Volcanological Center, and the Icelandic Meteorological Office. This research team is investigating strain partitioning in South Iceland with the goal of better quantifying the temporal and spatial pattern of strain in the Eastern Volcanic Zone, Iceland. These studies will allow insight into the role of central volcanoes and magmatic segmentation of ridges in accommodating plate motion and the formation of crust, and lead to a better understanding of hazards related to central volcanoes and fissure swarms that have historically produced the largest volume lava flows on earth and caused short-term (on the order of years) changes in regional climate (e.g., the 1783-84 Lakagígar fissure eruption). This research project will increase understanding of rift kinematics; this class of plate boundary, which includes the world's mid-ocean ridges, is usually inaccessible for detailed geodetic study.

世界大洋中脊系统的短期（不到一百万年）伸展过程由于其水下环境，对观测和量化是一个挑战。洋脊的岩浆分段导致容纳机制的沿着走向变化（例如，断层位移可能会向岩浆段的末端增加，在那里几乎没有岩浆可用于通过岩墙侵入来容纳伸展），进一步使应变信号复杂化。这项研究的目标是研究复杂的四维地壳形变场与发散板块边界区冰岛使用密集的宽孔径测量GPS和高速率连续GPS网络，很像地球镜板块边界观测网络，并建立在宾夕法尼亚州立大学，迈阿密大学，北欧火山中心，冰岛气象局该研究小组正在研究冰岛南部的应变分区，目的是更好地量化冰岛东部火山区应变的时空模式。这些研究将有助于深入了解中央火山和洋脊的岩浆分段在适应板块运动和地壳形成方面的作用，并有助于更好地了解与中央火山和裂缝群有关的危害，这些火山和裂缝群在历史上产生了地球上最大的熔岩流，并造成了区域气候的短期（数年）变化（例如，1783- 1784年拉卡吉加尔裂缝喷发）。这一研究项目将增进对裂谷运动学的了解;这类板块边界，包括世界大洋中脊，通常无法进行详细的大地测量研究。