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.

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).研究人员使用土地运动（重力，磁性，热流），卫星（重力，磁性，地球）和地震网络和数据中心（USARRAY，IRIS）中的现有数据；有些处理，有些是原始的，有些是新的处理方法是研究的一部分。他正在基于他最近的数学功能和统计估计理论的发展。这些是在各种采集几何形状中分析嘈杂和不完整的地球物理观察的共同基础，并根据统计推断和地球物理逆理论的最新见解，对它们进行了对它们的简约解释。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错误的严格分析，评估反转的唯一性以及与观众不确定性的有效交流。研究人员开发的工具是通过一系列旨在使公众在一系列先前的曝光和能力上通知公众的一系列宣传计划，从而为社区提供服务。这些活动的教育和宣传构建旨在训练年轻人进行科学而不是观察科学。我们如何在地震学中解决巨大的数据越来越大的“反问题”，地球的结构在最大的尺度或油田的尺度上都是通过地震或爆炸性地震波形的记录和建模来映射的？是什么表征了岩石圈的磁性特性，如何最好地从一级卫星观测中测量它们？我们希望提供的答案具有地质和地球物理性质和意义，但也影响了我们的日常生活。地震是一个明显的例子。但是，也许并非所有人都知道，油钻探需要岩石圈磁场的详细模型，以保持所需的轴承，或者诸如X射线层析成像和磁印等医学成像技术与我们探测地球内部的一些相同原理。我们关注的是理论和算法的发展，这些理论和算法有助于我们从观察值中提取信号，并促进其表示，分析和表征以及随后对建模中错误分布的评估，我们比首先应用这些方法的特定领域更广泛的目的。为了确保这一点，研究人员还与学生一起在中学和高中级别开发课程材料，这是一个动手的研究和写作丰富的新生研讨会，结合了地质学和地球物理学，以帮助塞浦路斯进行考古发掘，继续对网络上的计算机软件的出版和记录，以及在网络上的培训，以及对学生的培训，他们的培训，研究生和培训的研究生，研究生的研究生;研究整个社会。