Some US Parks that have active volcanoes formed as the result of subduction related processes are:. Other national parks lie along ancient subduction zones.
They used to contain volcanoes long ago, but over time the tall volcanoes were eroded away. Parks that show remnants of ancient volcanism are these will be links to individual park pages :.
Skip to main content. Toggle menu Go to search page. Search Field. Subduction Zone Volcanism. The Earth recycles itself! Many important natural resources are derived from subduction processes. Oil and natural gas reserves, fresh, highly fertile soils, and gold, silver, uranium, and diamonds are all formed at convergent plate boundaries. However, the beauty and abundance created by subduction comes at a high price. Powerful earthquakes and violent, unpredictable volcanic eruptions cause great destruction and death near convergent boundaries.
Underwater earth movements and explosions trigger enormous sea waves, called tsunamis, which travel across entire oceans to crash upon the distant shores of unsuspecting lands. Occasionally, volcanoes and volcanic islands erupt cataclysmically, essentially blowing themselves sky high and pumping great volumes of gas and ash into the upper layers of the atmosphere. Swept around the planet by the jet stream, the volcanic debris blocks incoming sunlight, causes global cooling, and can lead to widespread crop failure and famine.
Scientific knowledge of subduction is only a few decades old and still incomplete. Geologists continue to explore subduction zones, hoping that greater understanding of their complex processes will lead to methods of predicting and minimizing the dangers they pose. Dry land exists only because of subduction.
Continents are born from the destruction of oceanic crust. The magma produced at subduction zones hardens into granite, the bedrock of all the continents.
Once created, continents keep above sea level through further subduction. Important natural resources are derived from subduction processes. Oil and natural gas develops in the thick, highly organic sediments that accumulate around the plate boundary.
Volcanic rocks release nutrients as they weather forming some of the most fertile soils on Earth. Previously, it was widely assumed that subduction zones form spontaneously because of gravitational instability.
They published their results in Nature Geoscience on 27 August. Once active, subduction zones can exist for tens or even hundreds of millions of years, but how do they form? The first is mountain formation. Subduction zones always have mountain ranges caused by plate subduction. The next is volcanic activity as a plate is subducted the pressure and heat turns it into magma. These pockets of magma find paths to the surface and create volcanoes.
A good example is the subduction zone near Chile. The final sign is deep marine trenches. These are the best evidence of a subduction zone as they are visible evidence of the crease formed by subduction of a plate. The most famous is the Mariana Trench. This makes a lot of sense due to the geologic evidence of large impacts scattered around the world.
Understanding how subduction zones work is important because it helps scientist to identify areas of high volcanic and seismic activity. Monitoring these areas can help them warn people who live near them of imminent events and also people who could be affected by the side effects of such events such as ash clouds or tsunamis. Subduction continues to be one of the most powerful and dynamic processes on planet Earth and as technology improves we can come to understand more about this amazing process.
We have written many articles about the subduction zone for Universe Today.
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