Quaternary Geology and Climate Change

• Main Authors: Field Trip, Subaqueous Outwash
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2008
• Subjects: Glacial Lake; Ice Sheet
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.587.7154; http://mysite.science.uottawa.ca/idclark/Quat2333/labs/2008/South_Gloucester.pdf

Following the glacial maximum (ca 21,500 yr B.P.) a global warming trend began and the Laurentide Ice Sheet commenced its retreat from the Great Lakes Basin and the St. Lawrence Lowlands. However, it was not until after 11,500 that deglaciation reached the Ottawa area. The pro-glacial lake that existed in the St. Lawrence valley was expanding into the Ottawa valley by calving at the glacier front. Around this time, the ice dam at Québec City opened and the proglacial lake drained, becoming the Champlain Sea- an arm of the Atlantic Ocean stretching up the St. Lawrence lowands and the Ottawa Valley. Sediment was deposited in sub-aquous pro-glacial fans that remain as ridges of sand and gravel in the region.