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: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=710860
• 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潜艇限制的特征是大陆边缘是现代海洋开放的产物。尽管由于拥有大量的能源储量，它们的领土和经济重要性，但这些利润率在很大程度上没有被忽视，并且创造它们的过程尚未完全理解。裂痕的大陆边缘通常被归类为富含岩浆/岩浆/贫民区/贫民窟/非沃尔代岩边缘。加拿大的东海岸拥有两种类型的利润以及它们之间的过渡，为研究裂谷过程以及它们如何在裂痕的大陆边缘变化提供了自然实验室。也可以通过将海洋拼接在一起以研究共轭边缘的匹配程度，不对称性的发展以及这些不对称性是否在海洋开放之前是否存在，也可以获得丰富的见识。这些裂缝过程对随后的沉积物沉积和盆地的演变产生了深远的影响，以使对它们下面的地壳变异性有更好的了解可以降低勘探风险和成本。 我的研究计划涉及研究裂痕的大陆边缘及其缀合物，以便为这些利润率如何发展做出贡献，同时提供有关这些裂变过程如何影响石油系统的见解。短期目标是通过利用在加拿大东部的边缘以及共轭边际上获得的新的地球物理数据集，以更好地限制我们当前的裂痕大陆和过渡地壳的地壳模型。这些努力将涉及（1）地震加工工作，以提供改进的沿着和跨共轭对的地壳变化的图像； （2）详细的地震解释工作将地质边界与它们内部和跨共轭对之间的地球物理特征联系起来； （3）重力反演工作将新发现的地震约束扩展到更大的深度和更广阔的区域。长期的目标是继续对数据差距保留以及当前知识状态没有充分解释观察结果的关键区域，继续进行原始的科学地层尺度地震实验，并与行业，政府和国际合作者一起进行。 拟议的研究对能源勘探行业和各级政府都很重要，因为增强勘探的领土和经济影响。开发的重力反转方法对加拿大将特别具有战略意义，因为它们将提供一种低成本的方法来表征联邦政府已确定负责任发展作为研究优先事项的北极的深层结构。最后，将对10位高素质的地球科学家接受培训，从而在加拿大和国际上的学术界，政府和工业界进行工作。