Volcanoes
BY KAI BOWKER

Introduction
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There are three main types of volcanoes which are Shield Volcanoes,
Composite Volcanoes and Cinder Volcanoes.

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Shield volcanoes emit fluid lava and build up overtime to form very wide dome shapes, they can reach hundreds on miles across and many tens of thousands of feet high. These volcanoes have low slopes and almost entirely consist of frozen lavas.

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Composite volcanoes are also known as stratovolcanoes and they emit both fragmental material and viscous lava. They have many layers of sand or gravel-like volcanic rock called cinders or volcanic ash. These volcanoes are steeper than Shield ones because the viscous lava does not flow as readily.

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Cinder cones are smaller volcanoes that consist of loose grainy cinders and basically no lava. These volcanoes have very steep sides and a small crater at the top. They are produced from eruptions and emit pyroclastic matter, these layers then form the steep sides.

History/Description: Tseax
Cone
• Tseax Cone is a volcano located in British Columbia in the Northern Cordilleran Volcanic Province. This is one of Canada's most recently active volcanoes as there was an eruption in the late 18th century. The volcano is located above and east of the Tseax river and is one of the most accessible volcanic centres in
British Columbia. The base of it is roughly 290 meters in diameter but rests on the remains of a once larger cone.
The Eruption

• The eruption that took place in the 18th century killed approximately 2000 people. Many of these
Nigsa people died from volcanic gasses and poisonous smoke which was most likely CO2. This eruption was in actual fact caused by the Cascadia earthquake on January 26th, 1700 the most powerful earthquake in the northern pacific for the last 1000 years. History/Description: lo
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Jupiter is the largest planet in our solar system and therefore has many moons. Galileo Galilei discovered Io on January 8th in 1610 but had originally named it along with the other largest moons of
Jupiter after the Medici family and referred to them numerically.
The moon Io however is the most volcanically active body in the solar system, there are eruptions occurring all the time. Lo is only
5% larger than our moon which makes the eruptions all the more spectacular and if it weren't for Jupiter's gravitational pull Io would have become a cold and dead planet as it was once thought to be before. In 1979 Voyager 1 and 2 flew by Jupiter's moons and the images they transmitted back to earth showed 9 volcanic eruptions on Io.

Tseax & Io
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Volcanoes on Earth and volcanoes in space form in very different ways. On Earth volcanoes form due to plate tectonics, more specifically through divergence and subduction. The Pacific Ring of Fire is an area where most of the world's volcanoes are found because of the plates sub ducting along the Pacific coasts of
North America, South America, Asia, and the islands of the western Pacific Ocean.

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On Io and most other bodies in space there are no plate tectonics which leaves volcanoes to be made in other ways. Io’s eccentric orbit leads to a slight difference in Jupiter's gravitational pull between its closest and farthest points in its orbit causing a varying tidal bulge. This variation in Io’s shape is believed to interior frictional heating resulting in the volcanic activity.

Technology
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A large number of lives would be saved if warnings came early enough prior to an eruption. Volcanologists continue to make progress in their efforts to predict when active volcanoes will erupt. They use instrumentation to detect geological changes that may indicate a possible eruption such as:

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Seismographs are used to monitor earth tremors which are a common warning signal of volcanic activity.

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Changes in gas composition (i.e. SO , CO ) given off by the volcanoes and an increase in the rock temperature (thermal imaging).

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Physical changes in the shape and size (i.e. bulging) would indicate