Imaging and characterization of rifted continental margin structures using geophysical methods: seeking deeper constraints and their tectonic implications

使用地球物理方法对裂谷大陆边缘结构进行成像和表征：寻求更深层次的约束及其构造意义

• 批准号: RGPIN-2017-04258
• 负责人: Welford, JKim
• 金额: $ 1.68万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=751192
• 关键词: Imaging; characterization; rifted; continental; margin

Canada's submarine limits on the East Coast and in the Arctic are characterized by rifted continental margins, the products of the opening of modern oceans. Despite their territorial and economic importance due to hosting significant energy reserves, these margins remain largely underexplored and the processes that created them are not fully understood. Rifted continental margins are generally classified as magma-rich/volcanic margins or magma-poor/non-volcanic margins. Canada's East Coast hosts both types of margins as well as the transitions between them, providing a natural laboratory for studying rifting processes and how they vary along a rifted continental margin. Great insight can also be obtained by stitching the oceans back together to study how well the conjugate margins match, how asymmetries develop, and whether those asymmetries existed long before the oceans opened. These rifting processes have a profound impact on subsequent sediment deposition and basin evolution, such that developing a better understanding of the crustal variability beneath them can reduce exploration risk and cost. My research program involves studying rifted continental margins and their conjugates in order to contribute to global knowledge on how these margins develop while providing insights on how these rifting processes impact petroleum systems. The short-term goals are to better constrain our current crustal models of rifted continental and transitional crust by taking advantage of new geophysical datasets being acquired on the eastern Canadian margin, as well as on the conjugate margins. These efforts will involve (1) seismic processing work to provide improved images of the crustal variations both along and across conjugate pairs; (2) detailed seismic interpretation work to relate geological boundaries with their geophysical character both within and across conjugate pairs; and (3) gravity inversion work to extend newfound seismic constraints to greater depth and over a broader region. The longer-term goals are to continue to undertake original scientific crustal-scale seismic experiments, in conjunction with industry, government, and international collaborators, over key regions where data gaps remain and where the current state of knowledge does not adequately explain the observations.The proposed research is important to the energy exploration industry and all levels of government due to the territorial and economic impact of enhanced exploration. The gravity inversion methods developed will be of particular strategic importance to Canada as they will provide a low-cost approach to characterizing the deep structure of the Arctic where the federal government has identified responsible development as a research priority. Lastly, 10 highly qualified geoscientists will be trained for work in academia, government, and industry in Canada and internationally.

加拿大在东海岸和北极的海底界限的特点是断裂的大陆边缘，这是现代海洋开放的产物。尽管由于拥有大量的能源储备而具有领土和经济重要性，但这些利润率在很大程度上仍然未得到充分开发，而且创造它们的过程也没有得到充分理解。裂谷大陆边一般分为富岩浆/火山边和贫岩浆/非火山边。加拿大东海岸拥有这两种类型的边缘以及它们之间的过渡，为研究裂谷过程以及它们如何沿着沿着裂谷大陆边缘变化提供了天然实验室。通过将海洋拼接在一起，研究共轭边缘的匹配程度，不对称性如何发展，以及这些不对称性是否在海洋开放之前就存在，也可以获得很大的洞察力。这些裂谷过程对随后的沉积物沉积和盆地演化有着深远的影响，因此，更好地了解它们下面的地壳变化可以减少勘探风险和成本。我的研究计划涉及研究裂谷大陆边缘及其共轭物，以促进这些边缘如何发展的全球知识，同时提供这些裂谷过程如何影响石油系统的见解。短期目标是更好地限制我们目前的地壳模型的断裂大陆和过渡地壳，利用新的地球物理数据集正在获得的加拿大东部边缘，以及共轭边缘。这些努力将包括：（1）地震处理工作，以提供关于沿沿着和跨共轭对的地壳变化的更好的图像;（2）详细的地震解释工作，以将地质边界与共轭对内和跨共轭对的地球物理特征联系起来;（3）重力反演工作，以将新发现的地震制约因素扩大到更大的深度和更广的区域。长期目标是与工业界、政府和国际合作者一道，继续进行原始的科学地壳规模地震实验，在关键地区的数据差距仍然存在，目前的知识状态不能充分解释的意见。拟议的研究是重要的能源勘探行业和各级政府，由于领土和经济的影响，加强探索所开发的重力反演方法对加拿大具有特别的战略意义，因为它们将提供一种低成本的方法来确定北极深层结构的特征，联邦政府已将负责任的开发确定为研究的优先事项。最后，10名高素质的地球科学家将接受培训，在加拿大和国际学术界，政府和工业界工作。