erupted from a volcanic vent and moved down the flanks during the construction of a large volcano. Following extensive dissection, renewed volcanism produced a viscous series of lava flows forming its narrow, flat-topped, steep-sided northern limit and the northern end of the main ridge. The conduit for which these lava flows originated from was likely vertical in structure and intruded through older volcanics deposited during Fee's earlier volcanic events. This volcanic event was also followed by a period of erosion, and likely one or more glacial periods. Extensive erosion following the last volcanic event at Mount Fee has created the rugged north–south trending ridge that currently forms a prominent landmark. Ember Ridge, a volcanic mountain ridge between Tricouni Peak and Mount Fee, consists of at least eight lava domes composed of andesite. They were likely formed between 25,000 and 10,000 years ago when lava erupted beneath glacial ice of the Fraser Glaciation. Their current structures are comparable to their original forms due to the minimal degree of erosion. As a result, the domes display the shaps and columnar joints typical of subglacial volcanoes. The random shaps of the Ember Ridge domes are the result of erupted lava taking advantage of former ice pockets, eruptions taking place on uneven surfaces, subsidence of the domes during volcanic activity to create rubble and separation of older columnar units during more recent eruptions. The northern dome, known as Ember Ridge North, covers the summit and eastern flank of a mountain ridge. It comprises at least one lava flow that reaches a thickness of , as well as the thinnest columnar units in the Mount Cayley volcanic field. The small size of the columnar joints indicates that the erupted lava was cooled immediately and are mainly located on the dome's summit. Ember Ridge Northeast, the smallest subglacial dome of Ember Ridge, comprises one lava flow that has a thickness no more than . Ember Ridge Northwest, the most roughly circular subglacial dome, comprises at least one lava flow. Ember Ridge Southeast is the most complex of the Ember Ridge domes, consisting of a series of lava flows with a thickness of . It is also the only Ember Ridge dome that contains large amounts of rubble. Ember Ridge Southwest comprises at least one lava flow that reaches a thickness of . It is the only subglacial dome of Ember Ridge that contains hyaloclastite. Ember Ridge