The thrust front of the Northern Appalachians involves Ediacaran rift-related structures of the Laurentian margin that were re-worked in Taconic (Ordovician), Salinic (mainly Silurian) and Acadian (mainly Devonian) deformation events. Much of the thrust front is concealed under the Gulf of St. Lawrence, but Port au Port Peninsula, in western Newfoundland provides a cross-section through the Laurentian passive margin, overlying foreland basins, and the Humber Arm Allochthon. A large area of foreland basin strata is present in areas formerly mapped as Humber Arm Allochthon. Abrupt thickness changes and an abundance of fault-scarp-derived limestone conglomerate indicate that deposition was influenced by block faulting and differential subsidence in a basin undergoing active flexural extension. A coarsening upward trend in the Goose Tickle Group represents a transition from a distal to a proximal sediment source as the Humber Arm Allochthon was emplaced westwards. Goose Tickle Group separates two packages of allochthonous rocks. The West Bay Thrust Sheet, the lower package, represents the leading edge of the Taconic allochthon. Its timing of emplacement is constrained by Darriwilian 3 graptolites both above and below the thrust sheet. Its present-day configuration results from a combination of processes including thrusting, extension by gravity spreading, gravity gliding, and subsequent erosion of material that was deposited in the Goose Tickle Group. The structurally higher Lourdes Thrust Sheet is an out-of-sequence structure associated with Acadian (Devonian) orogenesis. High-angle faults show a protracted history of movement that includes early Taconic flexural extension, Acadian inversion, and later Carboniferous or Mesozoic strike-slip motion. The leading edge of the Humber Arm Allochthon was influenced by both thin-skinned and thick-skinned tectonics throughout the development of the Appalachian orogen.

中文翻译：

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加拿大阿巴拉契亚州纽芬兰西部 Humber Arm Allochthon 前沿的构造和前陆盆地开发

北阿巴拉契亚山脉的逆冲锋涉及劳伦边缘的埃迪卡拉裂谷相关构造，这些构造在塔康纪（奥陶纪）、盐碱纪（主要是志留纪）和阿卡迪亚（主要是泥盆纪）变形事件中被重新加工。大部分逆冲锋隐藏在圣劳伦斯湾之下，但纽芬兰西部的太子港半岛提供了穿过劳伦被动边缘、上覆前陆盆地和 Humber Arm Allochthon 的横截面。在以前绘制为 Humber Arm Allochthon 的地区存在大面积的前陆盆地地层。突然的厚度变化和丰富的断层陡崖衍生的石灰岩砾岩表明沉积受到块断层和盆地中的差异沉降的影响，该盆地正在进行弯曲伸展活动。随着 Humber Arm Allochthon 向西移动，Goose Tickle 群的粗化上升趋势代表了从远端沉积物源向近端沉积物源的过渡。Goose Tickle Group 分离出两包外来岩石。West Bay Thrust Sheet，较低的包装，代表了 Taconic 异地生物的前缘。它的进驻时间受到推力片上方和下方的 Darriwilian 3 笔石的限制。它现在的构造是由推力、重力扩散延伸、重力滑翔以及随后沉积在 Goose Tickle Group 中的材料侵蚀等过程组合而成的。结构较高的卢尔德逆冲断层是与阿卡迪亚（泥盆纪）造山作用相关的无序结构。大角度断层显示出长期的运动历史，包括早期的 Taconic 弯曲伸展、阿卡迪亚反转以及后来的石炭纪或中生代走滑运动。在阿巴拉契亚造山带的整个发展过程中，Humber Arm Allochthon 的前缘受到薄皮和厚皮构造的影响。