Which Comes First In Glacial Erosion Plucking Or Abrasion?

Which Comes First In Glacial Erosion Plucking Or Abrasion? Plucking occurs when rocks and stones become frozen to the base or sides of the glacier and are plucked from the ground or rock face as the glacier moves. This leaves behind a jagged landscape. Abrasion occurs when rocks and stones become embedded in the base