In the northeastern part of the Labrador Trough northwest of Fort Chimo, Quebec, a polydeformed metasedimentary sequence structurally overlies feldspathic gneisses. The gneisses are probably basement to the sediments. Rocks of the metasedimentary sequence were deformed into north-northwest vergent, isoclinal, recumbent folds and then refolded about subhorizontal northwest trending axes during the Hudsonian orogeny. The presence of early recumbent folds, apparently not involving basement, is compatible with the occurrence of gneiss domes and tight keels of metasediments in the eastern trough, as described by Dimroth, Gelinas and others. Recumbent folds like these could in part account for both the high metamorphic grades observed in the eastern trough and the commonly faulted contacts between metasediments and possible basement gneisses.

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