10Be dating Cordilleran-Laurentide ice-sheet separation during the last deglaciation

During the last glacial maximum, the Cordilleran and Laurentide ice sheets met just to the east of the Canadian Rocky Mountains, forming an ice-sheet saddle. When this saddle disappeared has implications on deglacial global sea-level rise and abrupt climate change as well as human migration patterns to the Americas. We will present new 10-Be boulder ages from six sites on a ~1100 km transect along the ice-sheet suture zone, to date Cordilleran-Laurentide ice-sheet separation. Results will directly test whether or not Cordilleran-Laurentide separation contributed to abrupt sea-level rise during meltwater pulse 1a (14.6-14.3 ka) in response to abrupt Bølling warming (14.6-14.0 ka).