The provenance and deformation of the Neoproterozoic Jacobsville Sandstone, which outcrops near the north and east shores of Lake Superior in the United States (Figure 1), is important for understanding two major tectonic episodes. It post-dates the formation of the Midcontinent Rift (MCR), the c. 1,100 Ma major rifting event which failed to split Laurentia (the Precambrian core of North America). The Jacobsville also contains a detrital record of collisional events that affected North America starting with the Grenville orogeny, the sequence of events from c. 1.3–0.98 Ga culminating in the assembly of the supercontinent Rodinia (Craddock, Craddock, Konstantinou, Kylander-Clark, & Malone, 2017; Dalziel, 1991; Rivers, 2012). The Jacobsville is a succession of feldspathic and quartzose sandstones, conglomerates, siltstones and shales deposited in terrestrial fluvial and lacustrine environments (Mitchell & Sheldon, 2016). Borehole measurements show that the Jacobsville might be up to 1 km thick (Ojakangas, Morey, & Green, 2001), and geophysical data suggest a maximum thickness ≥2 km (Kalliokoski, 1982). Although the Jacobsville was traditionally considered part of the Keweenawan Supergroup, the maximum age from detrital zircons is ~140 million years after extension ended, so the Jacobsville is not temporally related to MCR tectonic and magmatic activity. The Jacobsville unconformably overlies the ~1,100 Ma MCR volcanic and older rocks at many sites in the western study area (Kalliokoski, 1982). However, in the eastern area, at three boreholes and some outcrops, the Jacobsville and the youngest Oronto Group (Freda sandstones in Michigan and corresponding Mica Bay in Ontario) are in contact, probably unconformably (Ojakangas & Dickas, 2002). Received: 1 January 2020 | Revised: 18 April 2020 | Accepted: 22 May 2020 DOI: 10.1111/ter.12481

中文翻译：

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劳伦中大陆的新元古代沉积和构造：美国和加拿大雅各布斯维尔砂岩的碎屑锆石产地

美国苏必利尔湖北岸和东岸附近出露的新元古代雅各布斯维尔砂岩的来源和变形（图 1）对于理解两个主要的构造事件非常重要。它晚于中大陆裂谷（MCR）的形成，c。1,100 Ma 大裂谷事件未能分裂 Laurentia（北美的前寒武纪核心）。雅各布斯维尔还包含从格伦维尔造山运动开始影响北美的碰撞事件的碎屑记录，这是从 c. 开始的一系列事件。1.3–0.98 Ga 在超大陆 Rodinia 的组装中达到高潮（Craddock、Craddock、Konstantinou、Kylander-Clark 和 Malone，2017 年；Dalziel，1991 年；Rivers，2012 年）。Jacobsville 是一系列长石和石英砂岩、砾岩、沉积在陆地河流和湖泊环境中的粉砂岩和页岩 (Mitchell & Sheldon, 2016)。钻孔测量表明 Jacobsville 可能厚达 1 公里（Ojakangas、Morey 和 Green，2001 年），地球物理数据表明最大厚度 ≥ 2 公里（Kalliokoski，1982 年）。尽管 Jacobsville 传统上被认为是 Keweenawan 超群的一部分，但在延伸结束后，碎屑锆石的最大年龄约为 1.4 亿年，因此 Jacobsville 在时间上与 MCR 构造和岩浆活动无关。Jacobsville 不整合地覆盖在西部研究区许多地点的~1,100 Ma MCR 火山岩和更古老的岩石上（Kalliokoski，1982）。然而，在东部地区，在三个钻孔和一些露头处，Jacobsville 和最年轻的 Oronto Group（密歇根州的 Freda 砂岩和相应的安大略省的 Mica Bay）接触，可能不整合（Ojakangas & Dickas，2002）。收稿日期：2020 年 1 月 1 日 | 修订日期：2020 年 4 月 18 日 | 接受：2020 年 5 月 22 日 DOI：10.1111/ter.12481