加拿大纽芬兰纪念大学J. Kim Welford研究组揭示了纽芬兰和伊比利亚之间北大西洋南部异常无裂缝的海底，可通过古元古代以来的复合构造继承来解释。这一研究成果发表在2025年3月13日出版的《地质学》杂志上。

与大西洋其他地区相比，纽芬兰（加拿大东部）和伊比利亚（欧洲西南部）之间的海底异常缺乏断裂带。鉴于海洋断裂带通常与陆上继承的岩石圈弱点在空间上相关，它们的缺失可能表明边缘具有更强、更宽、更均匀的继承岩石圈结构。

光滑无裂缝的海底归因于大规模圣劳伦斯海角的长期影响，该海角（1）形成于古生代伊佩坦裂谷，（2）随后控制了阿巴拉契亚造山运动的时空演化，（3）最终决定了大西洋裂谷和海底扩张期间大浅滩大陆架的几何形状和纽芬兰-亚速尔断裂带的位置。

此外，根据邻近前寒武纪克拉通和祖先劳伦特造山带的空间分布，圣劳伦斯海角本身的形成归因于劳伦特建造期间和罗迪尼亚超大陆融合期间古元古代造山运动早期事件的继承，这表明岩石圈继承对随后构造运动的影响可能会持续近20亿年，并通过多个威尔逊旋回可以检测到。

附：英文原文

Title: Unusually fracture-free seafloor in the southern North Atlantic between Newfoundland and Iberia explained through compounding tectonic inheritance since the Paleoproterozoic

Author: J. Kim Welford

Issue&Volume: 2025-03-13

Abstract: The seafloor between Newfoundland (eastern Canada) and Iberia (southwestern Europe) is unusually devoid of fracture zones compared to other parts of the Atlantic Ocean. Given that oceanic fracture zones commonly spatially correlate with inherited lithospheric weaknesses onshore, their absence may be suggestive of margins with stronger, broader, and more homogeneous inherited lithospheric structures. Herein, the smooth fracture-free seafloor is attributed to the long-lived influence of the massive St. Lawrence promontory, which (1) formed during Paleozoic Iapetan rifting, (2) subsequently controlled the spatial and temporal evolution of Appalachian orogenesis, and (3) ultimately predetermined the geometry of the Grand Banks continental shelf and the location of the Newfoundland-Azores fracture zone during Atlantic rifting and seafloor spreading. Further still, based on the spatial distribution of the adjacent Precambrian cratons and orogenic belts within ancestral Laurentia, the formation of the St. Lawrence promontory itself is attributed herein to inheritance from earlier episodes of Paleoproterozoic orogenesis during the building of Laurentia and during the amalgamation of the Rodinian supercontinent, suggesting that the influence of lithospheric inheritance on subsequent tectonism may persist and be detectable for almost two billion years and through multiple Wilson cycles.

DOI: 10.1130/G53057.1

Source: https://pubs.geoscienceworld.org/gsa/geology/article/doi/10.1130/G53057.1/652879/Unusually-fracture-free-seafloor-in-the-southern