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The glacial stratigraphy and geomorphology of the western Lake Superior region record a complex sequence of late Wisconsinan ice advances and retreats of the Laurentide Ice Sheet from accumulation centers in Quebec and Hudson Bay. Geomorphic evidence indicates that three major late Wisconsinan events occurred, each marked by gradual buildup of ice, formation of a prominent moraine, and subsequent rapid ice retreat. The established radiocarbon chronology indicates that these three events culminated ca. 23-21, 16-15.5, and 13 14C ka, indicating that major glacial advances culminated immediately prior to Heinrich events H-2 and H-1, and that ice underwent rapid retreat during Heinrich events. The possible linkage between western Lake Superior region ice dynamics and Heinrich events is supported by the presence of indicator rock types in drift associated with each major glacial recession. These indicators suggest that progressive southward shifts of the Laurentide Ice Sheet ice divide accompanied each rapid glacial recession. Furthermore, lithologic evidence indicates that there were two episodes of ice divide shifts: one [approximately]400-600 km occurring during H-2, and a smaller shift occurring during H-1.

Jaco H Baas and Joachim Schonfeld and Gary N Meyer et al. criticized the association of local Heinrich events to overall ice sheet behavior. Contrary to their assertions, lithographic evidences support the theory that the three major Late Wisconsinan glacial flows of the Rainy lobe in Central Minnesota and the rapid ice retreat during the Laurentide Ice Sheet were related to Heinrich events. Carbonates found in the Hewitt till and other rocks from the Hudson Bay region manifested rich carbonate content, proof of sediment-laden iceberg from the Hudson Bay into the North Atlantic Ocean.