There are lingering questions about how far back in geologic time plate tectonic processes began. In the Paleoproterozoic of eastern Laurentia, accretion of intra-oceanic juvenile terranes along the leading edge of the Superior craton apex (Ungava indenter) during the interval 1.87–1.83 Ga was followed by collision with the Churchill plate at ca. 1.83–1.79 Ga. Orthogonal shortening along the indenter led to early obduction of the juvenile terranes including the ca. 2.0 Ga Watts Group ophiolite, followed by out-of-sequence thrusting at ca. 1.83 Ga of granulite-facies crystalline basement of the Sugluk block (Churchill plate) along the Sugluk suture. Exhumation and erosion of the Sugluk block led to deposition of a foreland/delta fan sequence in the Hudson Bay re-entrant (Omarolluk and Loaf formations of the Belcher Group), with detritus sourced exclusively from the Sugluk block. Continued collision led to critical wedge development and orocline formation in the Hudson Bay re-entrant, forming a strongly arcuate fold-thrust belt. On the other (eastern) side of the indenter, material flow during crustal shortening was accommodated by lateral extrusion of microplates towards a then open ocean basin, in a manner similar to present-day extrusion of Indochina as a response to India – South China craton convergence. In the Churchill plate hinterland W-NW of the indenter, propagating strike-slip faults resulted in the far-field extrusion and oblique exhumation of Archean crustal slices of the Rae crustal block. The 1.83–1.79 Ga Superior-Churchill collision accommodated a minimum of 500 km of continent–continent convergence, with resulting style and mechanisms of orogenic growth and material flow similar to those observed in the Alpine-Himalayan orogenic system.

关于地质时间板构造过程的开始时间还有很多疑问。在东部劳伦西亚的古元古代，在上盖克拉通顶（Ungava压头）的前缘，在上盖克拉通顶（Ungava indenter）的前缘增生了海洋内的幼体，随后与丘吉尔板块在ca碰撞。1.83–1.79 Ga。沿压头的正交缩短导致及早消灭了包括ca. 2.0 Ga Watts Group蛇绿岩，随后在约190°C时无序推入。沿Sugluk缝合线的Sugluk块（丘吉尔板）的1.83 Ga粒状相结晶基底。Sugluk区块的发掘和侵蚀导致哈德逊湾折返（Belcher集团的Omarolluk和Loaf地层）沉积了前陆/三角扇形序，碎屑仅来自Sugluk区块。持续的碰撞导致哈德逊湾折返中的楔形发育严重，并形成了斜线，形成了强烈的弓形褶皱冲断带。在压头的另一侧（东部），通过将微孔板横向挤压向当时开放的海盆来适应地壳缩短过程中的物料流动，其方式类似于今天对印度支那的挤压，以响应印度-华南克拉通收敛。在压头的丘吉尔板块腹地W-NW上，传播的走滑断层导致了Rae地块的太古地壳切片的远场挤压和倾斜掘出。1.83–1.79 Ga的上丘-丘吉尔碰撞发生了至少500公里的大陆-大陆交汇，