Structural geology of a gneissic terrain, Laurie Lake, northern Manitoba
Thomas, M. W.
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A three dimensional structural interpretation of complexly deformed Precambrian paragneisses exposed at Laurie Lake, Lynn Lake District, Manitoba is presented. An early episode of major isoclinal folding has produced repetitive structural levels of the various stratigraphic rock units, as they have been folded about subhorizontal axial surfaces. The amplitude/wavelength ratio of these initial isoclinal folds is extremely high and suggests nappe style folds. A metamorphic foliation and migmatitic layering accompanied the development of these early folds. Subsequent deformation of the major isoclines has resulted in the production of an irregular and complex "dome and basin type" interference pattern. These later structures exhibit a general conformity in plunge completely around their closure, indicating severe elongation down plunge. Minor folds, metamorphic foliation, and metamorphic lineation were developed during the later event.