Towards a High Resolution, Three-component Velocity Field for the Central Andes

本研究将使用空间大地测量（GPS和InSAR）来创建过去十年安第斯山脉中部地壳速度的高空间分辨率三分量图。主要目标是成像地震间形变场沿走向的可能变化。虽然地震间变形场本身就很有趣，并且可以用来确定俯冲界面的哪些部分被锁定（并且可能在未来的地震中破裂），但目标是对这种变形进行建模，以便将其移除。本研究旨在分离细微的低振幅变形，包括：1)近期俯冲带地震后的大块震后松弛。2)与长期造山活动有关的浅层地壳断层地震运动。3)地壳下深层储层的岩浆运动和浅层储层的低速率岩浆运动。本研究将使用与先前研究类似的方法（例如，Peltzer等人，2001年，Wright等人，2001年），但将数据量和空间覆盖范围增加1-2个数量级，从先前研究中使用的10个场景的InSAR数据增加到近1000个场景。这项研究将有助于更好地描述两种不同环境下地震的危害——俯冲带和大陆内。该项目还将扩展我们之前对数百座火山的活动变形的调查，这些活动变形可能表明岩浆运动和进一步评估喷发危险的必要性。在这项研究中开发的软件将成为公开可用的。这项研究将包括对研究生和本科生的培训，并将支持一个早期的职业科学家。

Towards a high resolution, three-component velocity field for the central AndesThis study will use space geodetic measurements (GPS and InSAR) tocreate a high spatial resolution, three-component map of crustalvelocity in the central Andes during the past decade. The primarygoal is to image possible along-strike variations in the inter-seismicdeformation field. While the inter-seismic deformation field isinteresting in its own right, and can be used to determine which partsof the subduction interface are locked (and might rupture in futureearthquakes), the objective is to model this deformation so that itcan be removed. This study seeks to isolate subtle low-amplitudedeformation, including: 1) Bulk post-seismic relaxation followingrecent subduction zone earthquakes. 2) Aseismic motion on shallowcrustal faults related to long-term mountain-building. 3) Magmamovements in deep sub-crustal reservoirs and at low rates in shallowchambers. This study will use methods similar to those of previousstudies (e.g., Peltzer et al., 2001, Wright et al., 2001), but willincrease the amount of data and spatial coverage by 1-2 orders ofmagnitude, from the 10's of scenes of InSAR data used in previousstudies to nearly 1000 scenes.This study will help to better characterize hazards from earthquakesin two different environments -- subduction zones and within thecontinents. This project will also extend our previous surveys ofhundreds of volcanoes for active deformation that could indicatemagmatic movements and the need for further assessment of eruptivehazard. The software that will be developed in this study will becomepublicly available. This study will involve the training of graduateand undergraduate students, and will support an early careerscientist.