Collaborative Research: Colorado Rockies Experiment and Seismic Transects (CREST): Time-space Patterns of Cenozoic Uplift-magmatism and their Correspondence to the Aspen Anomaly

这个项目是之前CD资助的一系列落基山项目的后续项目，该项目建立在科罗拉多州中部地幔低速异常的发现基础上。拟议的项目涉及各种技术，以解决所谓的“阿斯彭异常”的原因、其历史及其对地壳演化的影响。PI感兴趣的是地幔变化引起的地表地形变化之间的联系。他们观察到，阿斯彭异常位于落基山脉最高部分的下方。他们将低地幔地震速度等同于低地幔密度，从而导致了隆起。他们将调查该地区地幔中非常大的速度变化是否是：a)在岩石圈或软流圈，b)反映由新生代构造作用重新激活的元古界岩石圈缝合，c)由烟柱引起，d)由熔体的存在引起。这些都是大陆动力学的重要和相关问题。具体来说，PIS将使用：-被动地震学，使用层析成像、接收器功能、面波和各向异性来更好地定义异常；-地质学研究(岩浆史、低温热年代学、构造地貌学)以确定新生代构造和岩浆历史，以定义长期和现代历史；-地形隆起和地幔过程的地球动力学模型，以研究它们之间的联系。

0607534KirbyThis project is a follow up to a series of previous CD funded Rocky Mountain focused projects building on the discovery of a low velocity anomaly in the mantle beneath central Colorado. The proposed project involves a wide variety of techniques assembled to address the cause of the so called "Aspen anomaly", its history, and its effect on crustal evolution. The PIs are interested in the connection between changes in the mantle causing modification of surface topography. They have observed that the Aspen anomaly is located beneath the highest portion of the Rocky Mountains. They equate low mantle seismic velocities with low mantle densities to cause uplift. They will investigate whether the very large velocity variations in the mantle beneath this area are: a) in the lithosphere or asthenosphere, b) reflect Proterozoic lithospheric sutures reactivated by Cenozoic tectonism, c) are caused by a plume, and d) are caused by the presence of melt. These are all important and relevant questions for Continental Dynamics. Specifically, the PIs will use: - passive seismology to better define the anomaly using tomography, receiver functions, surface waves, and anisotrophy;- geological studies (magmatic history, low temperature thermochronology, tectonic geomorphology) to identify Cenozoic tectonic and magmatic history to define long term and current history;- geodynamical models of topography uplift and mantle processes to study their connection.