CAREER: From Robust, Reproducible Geophysical Inference to Geological Interpretation: New Perspectives on the Continental Lithosphere

职业：从稳健、可重复的地球物理推论到地质解释：大陆岩石圈的新视角

• 批准号: 1150145
• 负责人: Frederik Simons
• 金额: $ 50万
• 依托单位: Princeton University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-15 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1150145&HistoricalAwards=false
• 关键词: CAREER; Robust; Reproducible; Geophysical; Inference

For this CAREER proposal the researcher will study the structure of the lithosphere, from a characterization of its long-term mechanical strength (elastic thickness from gravity and topography inversions) and its short-term elastic response (seismic structure all the way down to the oil exploration scale), to its propensity for deformation in the context of plate tectonics and geodynamics (via the anisotropies detectable in both types of observables). The researcher uses existing data from land campaigns (gravity, magnetics, heat flow), satellites (gravity, magnetics, geodesy) and seismic networks and data centers (USArray, IRIS); some processed, some raw, some for which new processing methods are very much part of the research. He is building on his recent development of mathematical functions and statistical estimation theory. These share the common ground of analyzing noisy and incomplete geophysical observations in a variety of acquisition geometries, and building parsimonious interpretations of them based on recent insights in statistical inference and geophysical inverse theory. In this way the geophysical and geological interpretation that he produces is accompanied by a rigorous analysis of modeling errors, an assessment of the uniqueness in the inversion, and the effective communication of uncertainty to the audience. The tools the researcher develops are put at the service of the community via a series of outreach initiatives aimed at enabling rather than merely informing the public over a range of prior exposure and ability, from middle-school students to post-doctoral scholars. The education and outreach building on these activities are geared towards training young people to do science rather than watching it being done.How strong is the rigid outer layer of the Earth called the "lithosphere", how is this strength best measured, and how does it relate to other geophysical and geological observables such as the depth and frequency of earthquake occurrence, the measurable heat flow through the crust, the large-scale patterns of deformation and mountain building? How do we tackle huge data-rich "inverse problems" in seismology, by which the structure of the Earth at both the largest scale or at the scales of an oil field is mapped via the recording and modeling of earthquake- or explosively generated seismic waveforms? What characterizes the magnetic properties of the lithosphere and how are they best measured from primary satellite observations? The answers we hope to provide are of a geological and geophysical nature and significance, but also impact us in our daily lives. Earthquakes are an obvious example; but perhaps not everyone knows, that oil drilling requires detailed models of the lithospheric magnetic field in order to keep the desired bearing, or that medical imaging techniques such as x-ray tomography and magneto-encephalography work with some of the same principles by which we probe the Earth's interior. With our focus on the development of theory and algorithms that help us extract signal from observations, and facilitate its representation, analysis and characterization, and the subsequent evaluation of the distribution of errors in the modeling, we serve a broader purpose than the specific areas in which these methods are first applied. To ensure this, the researcher also develops lesson materials at the middle-school and high-school level with the student as participant, a hands-on research and writing-heavy Freshman Seminar that combines geology and geophysics to aid with archaeological excavations on Cyprus, the continued publication and documentation of computer software on the web, and the mentoring of undergraduates, graduate students and post-docs on their path to delivering ``reproducible research'' to the society at large.

对于这个职业生涯的建议，研究人员将研究岩石圈的结构，从其长期的机械强度的表征（重力和地形反演的弹性厚度）及其短期弹性响应（一直到石油勘探规模的地震结构），在板块构造和地球动力学背景下的变形倾向（通过在两种类型的可观测量中可检测到的各向异性）。研究人员使用来自陆地活动（重力，磁力，热流），卫星（重力，磁力，大地测量）和地震网络和数据中心（USAray，IRIS）的现有数据;一些处理，一些原始，一些新的处理方法是研究的重要组成部分。他正在数学函数和统计估计理论的最新发展的基础上再接再厉。这些共享的共同点分析噪声和不完整的地球物理观测在各种采集几何形状，并建立他们的最新见解的基础上，在统计推断和地球物理反演理论的吝啬的解释。通过这种方式，他产生的地球物理和地质解释伴随着对建模误差的严格分析，对反演中的独特性的评估，以及对观众的不确定性的有效沟通。研究人员开发的工具通过一系列旨在使而不仅仅是在一系列先前的曝光和能力，从中学生到博士后学者告知公众的外联举措，为社区服务。以这些活动为基础的教育和外联活动旨在培训年轻人从事科学工作，而不是看着科学工作。被称为“岩石圈”的坚硬的地球外层有多强，如何最好地测量这种强度，以及它与其他地球物理和地质观测指标（如地震发生的深度和频率，通过地壳的可测量热流，大规模的变形和造山运动我们如何处理地震学中数据丰富的“逆问题”，即通过记录和模拟地震或爆炸产生的地震波形来绘制最大尺度或油田尺度的地球结构？岩石圈的磁性特征是什么？如何从原始卫星观测中最好地测量它们？我们希望提供的答案是地质和地球物理性质和意义，但也影响我们的日常生活。地震就是一个明显的例子;但也许不是每个人都知道，石油钻探需要岩石圈磁场的详细模型，以保持理想的方位，或者医学成像技术，如X射线断层扫描和脑磁图，与我们探测地球内部的原理相同。我们专注于理论和算法的发展，帮助我们从观测中提取信号，并促进其表示，分析和表征，以及随后对建模中误差分布的评估，我们的目的比这些方法首次应用的特定领域更广泛。为了确保这一点，研究人员还开发了中学和高中阶段的教材，学生作为参与者，一个动手研究和写作繁重的新生研讨会，结合地质学和地球物理学，以帮助在塞浦路斯进行考古发掘，继续出版和记录计算机软件在网络上，并指导本科生，研究生和博士后在他们的道路上提供“可复制的研究”，以整个社会。