GOALI: Seismic interferometry and reflection imaging of the deep crust

目标：地壳深部的地震干涉测量和反射成像

• 批准号: 1451216
• 负责人: Anne Sheehan
• 金额: $ 22万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-01 至 2020-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1451216&HistoricalAwards=false
• 关键词: GOALI; Seismic; interferometry; reflection; imaging

The proposed research aims to merge methods of academic passive source seismology with industry active source seismology for enhanced subsurface seismic imaging at a variety of scales. The emerging methods of seismic interferometry will be explored and applied. Work on the proposed project will be used to improve corrections for near-surface variations, develop schemes for incorporating virtual source methods into seismic reflection imaging, and to further utilize seismic data sets collected in the past. Methods will be applied both to sedimentary basins of economic interest and to deep Rocky Mountain fault systems, with implications for crustal deformation processes and origin of the deep structures that formed the Rocky Mountains. The collaboration with industry will benefit the project through access to computer hardware and software, and to industry signal processing and large data set expertise.In this project the utility of including virtual source gathers and velocity structures derived from interferometry in seismic reflection studies will be explored. The two main approaches that will be followed include development and comparison of near-surface statics corrections derived from surface wave ambient noise tomography to those from traditional refraction statics, and active source interferometry applied to reflection surveys. Rather than restricting the interferometry to ambient background noise, the virtual source methods take advantage of waveform recordings of signals such as active source blasts, mine blasts, and distant and local earthquakes. The study will utilize a modern data set from a combined active-passive seismic experiment (Bighorn Arch Seismic Experiment or BASE), and a 1970?s era vibroseis data set (COCORP Wind River mountains experiment). The main geologic targets in each case are the deep faults beneath the Laramide Arches and flanking basement, including suggested crustal detachment features widely invoked in structural models. The proposed contributions will be of general use beyond this particular geologic environment and geographic province, and will more fully exploit existing data sets. A comparison of resulting images from this proposed study can provide an opportunity to evaluate the effectiveness of each imaging method with diverse data sets, and the accompanying active source experiments provide an important check on results.

拟议的研究旨在将学术被动震源地震学的方法与工业主动震源地震学的方法相结合，以在不同的尺度上增强地下地震成像。将探索和应用地震干涉测量的新兴方法。拟议项目的工作将用于改进对近地表变化的校正，制定将虚拟震源方法纳入地震反射成像的计划，并进一步利用过去收集的地震数据集。这些方法将同时应用于具有经济意义的沉积盆地和落基山脉深部断裂系统，涉及地壳变形过程和形成落基山脉的深部结构的起源。与工业界的合作将使该项目受益于获得计算机硬件和软件，以及工业信号处理和大型数据集专业知识。在这个项目中，将探索在地震反射研究中包括来自干涉测量的虚拟震源道集和速度结构的用途。接下来将采用的两种主要方法包括发展和比较基于面波环境噪声层析成像和传统折射静校正的近地表静校正量，以及应用于反射测量的有源干涉法。虚拟震源方法不是将干涉测量限于环境背景噪声，而是利用信号的波形记录，例如活动震源爆炸、地雷爆炸以及远距离和本地地震。这项研究将利用现代主被动联合地震试验(Bighorn Arch地震试验或基地)的数据集和1970年代S时代的可控震源数据集(Cocorp Wind River Mountain实验)。每种情况下的主要地质目标都是拉拉米勒拱形和两侧基底之下的深断裂，包括在构造模型中广泛引用的建议的地壳拆离特征。拟议的贡献将在这一特殊的地质环境和地理省之外普遍使用，并将更充分地利用现有的数据集。这项拟议研究的结果图像的比较可以提供一个机会，用不同的数据集来评估每种成像方法的有效性，并且伴随的有源源实验提供了对结果的重要检查。