[1] Mount Silverthrone, an eroded lava dome on the caldera's northern flank, which is 2,864 metres (9,396 ft) high, may be the highest volcano in Canada.

It can be reached by helicopter or — with major difficulty — by hiking along one of the several river valleys extending from the British Columbia Coast or from the Interior Plateau.

[5] The intrusions are thought to be subvolcanic bodies associated with a volcanic front that was active in the Miocene, during early stages of subduction of the Juan de Fuca Plate.

[6] With the notable exception of King Island, all the intrusive and eruptive rocks are calc-alkaline, mainly granodioritic bodies and dacite ejecta.

[6] On a broader scale, the intrusive and eruptive rocks are part of the Coast Plutonic Complex, which is the single largest contiguous granite outcropping in North America.

[7] The intrusive and metamorphic rocks extend approximately 1,800 kilometres (1,100 mi) along the coast of British Columbia, the Alaska Panhandle and southwestern Yukon.

[1] Potassium-argon dates of 750,000 and 400,000 years on rhyolitic lava domes above the basal breccia are consistent with the high rates of uplift and erosion recorded elsewhere in the Coast Mountains.

However, as at other calderas, eruptions at Silverthrone are explosive in nature, involving viscous magma, glowing avalanches of hot volcanic ash and pyroclastic flows.

Most of the caldera's eruptive products have been heavily eroded by alpine glaciers and are now exposed in precipitous slopes extending from near sea level to elevations less than 3,000 metres (9,800 ft).

Anomalously old potassium-argon dates of 1,000,000 and 1,100,000 years were obtained from a large lava flow at least 10 kilometres (6.2 mi) long in the postglacial Pashleth Creek and Machmell River valleys.

At high elevations, proximal breccia and cinders from several eroded cones rest on coarse colluvium derived from the older parts of the volcanic complex.

[19] Seismic data suggests that these volcanoes still contain live magma plumbing systems, indicating possible future eruptive activity.

[3] The seismic activity correlates both with some of Canada's most youthful volcanoes, and with long-lived volcanic centers with a history of significant explosive behavior, such as the Silverthrone Caldera.

[22] For this reason, additional projects to study Silverthrone and other Garibaldi belt volcanoes to the south are being planned by the Geological Survey of Canada.

[23] The explosive nature of past eruptions at Silverthrone Caldera suggests that this volcano poses a significant long-distance threat to communities across Canada.

Ash columns could rise to several hundred meters above the volcano which would make this a hazard for air traffic along the coastal airway between Vancouver and Alaska.

Because the Silverthrone region is in a remote and exceptionally rugged part of the Coast Mountains, danger from lava flows would be low to moderate.

Magma with high to intermediate levels of silica (as in andesite, dacite or rhyolite) commonly move slowly and typically cover small areas to form steep-sided mounds called lava domes.

Globally, large explosive eruptions that inject a tremendous volume of sulfur aerosols into the stratosphere can lead to lower surface temperatures and promote weakening of the Earth's ozone layer.

[29] The existing network of seismographs has been established to monitor tectonic earthquakes and is too far away to provide a good indication of what is happening beneath the caldera.

[29] A likelihood of Canada being critically affected by local or close by volcanic eruptions argues that some kind of improvement program is required.

[3] With increasing distance and declining numbers of seismographs used to indicate seismic activity, the prediction capability is reduced because earthquake location and depth measurement accuracy decreases.

[3] At "carefully monitored volcanoes both the located and noticed events are recorded and surveyed immediately to improve the understanding of a future eruption.