Structural and tectonic evolution of orogenic belts, with an emphasis on kinematics of shear zones, accretionary/collisional orogens and Archean tectonics

造山带的结构和构造演化，重点是剪切带、增生/碰撞造山带和太古代构造运动学

• 批准号: RGPIN-2019-04305
• 负责人: Lin, Shoufa
• 金额: $ 3.13万
• 依托单位: University of Waterloo
• 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=750855
• 关键词: Structural; tectonic; evolution; orogenic; belts

The long term goal of my research is to develop a stronger understanding of structural and tectonic evolution of mountain belts, the evolution of tectonic processes through time, and the structural and tectonic control on mineralization. The proposed study will focus on three ancient mountain belts of contrasting ages and styles: the Proterozoic to Mesozoic South China Block and the Paleozoic Central Asian Orogenic Belt (CAOB) in China and the Archean Superior craton in Canada.       Continental margins, especially passive margins, commonly have irregular shapes and exhibit promontories and reentrants. Where this is the case, collision between two continents is expected to start at a promontory or between two promontories. This has major implications for tectonic evolution of orogens, but has drawn only limited attention. A better understanding of the role of irregular continental margins in collision through a study of the Early Paleozoic Orogen in South China is one of the objectives of the proposed study. Promontory collision offers a solution to the biggest puzzle concerning South China in the early Paleozoic, that is, a major tectono-thermal event in South China, with characters of a collisional orogeny, took place tens of millions of years after the Gondwana supercontinent had been assembled and collision appeared to have been over.       Our work in the CAOB will focus on the timing and processes of the final closure of the Paleo-Asian Ocean, through a detailed study of a Carboniferous-Permian volcano-sedimentary sequence and syntectonic intrusions and a potential ophiolite sequence. We will also pay special attention to the geometry, kinematics, temporal evolution and the tectonic significance of major terrane-bounding shear zones.       Our work on the Superior craton has led to the recognition of evidence for both vertical and horizontal tectonism and, more importantly, for their synchronous operation. We have proposed that synchronous vertical and horizontal tectonism was an important process in the Neoarchean and represented a transition from dominant vertical tectonism in the Meso-(and Paleo-?) Archean to dominant horizontal tectonism in the Proterozoic and Phanerozoic. We will continue to test these interpretations and their general applicability.       Our field-based study will be aided by numerical modelling, using a new code developed by our team that covers the time component by solving a generalized non-steady system with finite element method. The code is optimal for simulating geological processes with large deformation and for examining structural evolution in complex orogenic processes.       These research efforts will train at least five graduate and many more undergraduate students in structural geology and tectonics. They will gain a competitive edge from our field-based, multidisciplinary and collaborative research experience.

我的研究的长期目标是对山带的结构和构造演变，构造过程的进化以及矿化的结构和构造控制，对结构和构造的进化有更深入的了解。拟议的研究将重点关注三个古老的对比年龄和样式的古老山地：中生代南方街区和中国的古生代中亚造山带（CAOB）和加拿大的Archean Superior Cranton。大陆边缘，尤其是被动边缘，通常具有不规则的形状，并且表现出诺言和重感。在这种情况下，预计两个连续性之间的碰撞将从海角或两个海角之间开始。这对Orogens的构造演变具有重大影响，但仅引起了有限的关注。通过对中国南部的早期基因造成的研究，可以更好地理解不规则大陆边缘在碰撞中的作用，这是拟议研究的目标之一。海角碰撞为早期古生代中国南部的最大难题提供了一种解决方案，即在中国南部发生的一项主要的Textono-thermal事件，具有碰撞的造山学特征，发生在冈瓦纳超大陆后数百万年内，已经组装了成立，并且碰撞似乎已经结束了。我们在CAOB中的工作将通过对石炭纪 - 珀米式火山式序列和语法侵入和潜在的粘纤维序列的详细研究，将重点放在古 - 亚洲海洋最终封闭的时间和过程上。我们还将特别注意几何形状，运动学，临时进化和主要地面剪切区的构造意义。我们在上级克拉顿（Craton）上的工作使人们认识到垂直和水平构造的证据，更重要的是，它们的同步操作。我们已经提出，同步的垂直和水平构造是新政治中的一个重要过程，它代表了从中质和phanerogic中介质（和古）的显着垂直构造向主导的水平构造的过渡。我们将继续测试这些解释及其一般适用性。我们已经提出，同步的垂直和水平构造是新政治中的一个重要过程，它代表了从中质和phanerogic中介质（和古）的显着垂直构造向主导的水平构造的过渡。我们将继续测试这些解释及其一般适用性。我们将使用团队开发的新代码来帮助我们通过使用有限元方法求解广义的非态系统，从而涵盖时间组件。该代码对于模拟具有较大变形的地质过程和检查复杂造基因过程中的结构演化是最佳的。这些研究工作将培训至少五名毕业生和更多的结构地质和构造学本科生。他们将从我们基于现场的，多学科和协作研究经验中获得竞争优势。