Omission

As is commonly the case with those who review our work, Benn and Evans fail to relate bedrock erosional marks to the meltwater hypothesis. Such erosional marks in granite and gneiss in the French River area of Georgian Bay provide very strong evidence for broad, catastrophic subglacial floods (Kor et al., 1991). There is no possibility of interpreting them otherwise (Shaw, this volume, Chapter 4). The meltwater hypothesis is well supported by evidence from the streamlined hills and fluted bedrock of the Scablands and from the French River erosional marks, all of which require extensive, turbulent sheet floods for their formation.

Benn and Evans also ignore some of the main evidence for large-scale erosional events such as erosion into undisturbed preglacial gravels in the Blackspring Ridge flute field in south-central Alberta (Munro-Stasiuk & Shaw, 2002). They make the blanket statement that glacitectonite and till should appear in these landforms. They also ignore the observation that many landforms have truncated surfaces representative of a landform unconformity (e.g. Munro & Shaw, 1997; Munro-Stasiuk & Shaw, 2003, Sharpe et al., 2004).

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