One of the most visited active volcanoes in Canada is Mount Garibaldi due to its proximity
to Vancouver.
It last erupted approximately 10,000 years ago, sending viscous and thick dacite lava
more than 17 kilometers to the southwest.
However, Mount Garibaldi is not the only nearby volcanic feature.
A mere 5 kilometers to the north is a completely separate volcano, which contains a number
of fascinating and unusual features such as the black tusk.
Since the end of the last ice age, this volcanic complex, termed the Garibaldi Lake volcanic
field has produced more numerous eruptions than the neighboring Mount Garibaldi volcano.
Recent analysis have confirmed the presence of three young eruptions between 8,000 and
15,000 years ago.
This video will discuss this volcano and it’s recently dated new eruptions.
The Garibaldi Lake volcanic field is located in southwestern British Columbia, where it
is 71 kilometers north of the city of Vancouver.
This volcanic complex contains an assortment of stratovolcanoes, lava domes, cinder cones,
and even a prominent tuya.
These vents are spread across an area of 150 square kilometers, and originated from magma
related to offshore plate subduction.
This complex began forming approximately 1.3 million years ago, when a volume of andesitic
lava erupted onto the surface.
The molten rock cooled as a gray color, and through vulcanian style explosive eruptions
began building a central volcanic cone.
In the span of only 200,000 years, a towering stratovolcano called the Black Tusk had been
constructed.
Around 1.1 million years ago, this volcano became dormant, and would not erupt again
until 210,000 years ago.
A more viscous variety of andesite then explosively erupted, and built a towering lava dome on
its summit.
In the time since, the majority of the lava dome has eroded away, leaving behind the much
harder central core which supplied magma to this volcano.
This core can now be seen today through the unusual spires at its summit.
Beginning around 1.2 million years ago, a second stratovolcano to the south simultaneously
erupted alongside the Black Tusk volcano.
Over the next several hundred thousand years, Mount Price was constructed to become a tall
gray colored volcano.
As eruptions from this volcano continued intermittently over time, lava it erupted slowly became more
viscous.
One of these eruptions between glacial periods built a large rounded lava dome, which is
shown on screen.
Around 9,000 years ago, a satellite peak of this volcano, called Clinker Peak was the
site of the two most recent eruptions from the overall volcanic complex.
These eruptions formed unusually fluid andesite lava flows, which flowed approximately 6.5
kilometers to the west.
The northern lava flow eventually blocked the exit of glacial runoff, allowing the large
Garibaldi Lake to form.
The southern lava flow stopped in a valley, creating a large cliff face which is now the
site of frequent landslides.
With all of this being said, the most famous feature of this volcanic field is a feature
simply known as "the table".
It represents a large tuya which formed about 11,500 years ago.
Tuyas form underneath glacial ice, and contain steep slopes and a flat top.
Overall, the odds of a future eruption are approximately 1 in 4,000 each year.
The main danger posed by any future eruption are catastrophic lahars.
Although unlikely, an explosive eruption is possible on the western edge of Garibaldi
Lake.
Such an explosion could remove the natural dam created by a recent eruption, causing
more than a cubic kilometer of water to pour out from the breach, destroying a number of
nearby towns and coastal cities, much like seen at the Nevado Del Ruiz volcano in 1985.
More likely, the next eruption from this volcano will create another viscous lava flow.
When sections of this flow collapse, it will generate pyroclastic flows.
Areas which could be effected by these hazards during even a small eruption include Garibaldi,
Squamish, Garibaldi Highlands, and Brackendale.
In a previous video, I had rated this volcano in the moderate threat category.
However, due to the confirmation of new and young eruptions, it greatly raises the risk
posed by this volcanic complex.
Using the US Geological Survey method of rating volcanoes, Garibaldi Lake would be classified
as a very high threat volcano.
I hope that you enjoyed this video!
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