Stratigraphic and structural updates to rocks along the southeast side of Wekusko Lake, Manitoba
New mapping in the southeast corner of Wekusko Lake divides rocks into four stratigraphic assemblages: 1) N-MORB like basalts of the south Weksuko assemblage, 2) trachyandesite and dacite of the Puella Bay assemblage, 3) greywacke and mudstone of the Burntwood assemblage, and 4) volcanic and fluvial sediments of the Herb Lake assemblage (part of the broader Missi group). Age dating of the Broad Bay pluton and field observations constrain the age of the Puella Bay assemblage and by association provide a minimum age for N-MORB basalts of the South Weksuko assemblage. A dacite tuff breccia interpreted to stratigraphically overlying cross-bedded sandstone on the northwest limb of the Herb Lake fold has an age that is older than the 1836 ± 1.3 Ma Chickadee Rhyolite in the core of the fold and supports field observations that these volcanic rocks form a large-scale syncline. A crystallization age the Stuart Lake pluton provides minimum age for sedimentation and helps constrain deformation associated with development of the Herb Lake syncline and Stuart Lake anticline.