By Amina Yahaya
The earth we all walk on is pretty cool and stable. But a lot of incredible stuff are going on far beneath this seemingly cool surface. Miles below our feet is a raging inferno, boiling and scotching. Yes scotching! As scotching as the surface of the sun. Yet all that energy and forces wants to escape, to the very surface of the Earth.
Ok, what’s so hot and why, you may ask? The earth crust is made up of basically four layers: the Lithosphere, mantle, inner core and outer core. From the mantle down to the other layers are piping hot mush, constituting a Mixture of runny rock not quite liquid or solid known as magma. The magma as a result of pressure and other factors we would later examine finds its way through vents then erupt on the Earth surface as volcanoes. This eruption spew out lava, ash and Gases.
Suffice to say, a volcano is a hole or opening in the earth’s interior from where molten rock and gases ooze out. When these magma reaches the earth’s surface, it becomes lava, lava fragments, and lava flows which cools and solidifies to form igneous rock.
Volcanoes start out as bright orange at a whooping (1000-1500) Celsius. As it cools, the color changes to bright red at (800-1000) Celsius. Then it changes to dark red at (650-800) Celsius, and finally to brownish red at (500-650) Celsius. Needless to say, noting can survive inside an active volcano because anything that goes into it would be burnt in seconds.
Volcanoes can be classified into three, namely, active, dormant or extinct. In an active volcano, volcanic activities are in continuing eruption status or have a recent history of eruption. For instance, Stromboli volcano in Italy has been awake for the last 2000 years, and it has been erupting longer than any other volcano in the world. There are over 1500 active volcanoes around the world as at October 2021 including the recent La Palma Volcano.
A dormant volcano, on the other hand, is an active volcano that has erupted in the past, not erupting at the moment but likely to erupt in the future. Mount Kilimanjaro in Tanzania, is the nearest example of a dormant volcano. Whereas, when a volcano has been dormant for more than 10,000 years, it is considered extinct. An extinct volcano no longer has a lava supply nor is it near an active geological hot spot. Thus very unlikely to ever erupt again.
Volcanoes can be caused by; buoyancy of magma around a particular spot, usually around tectonic plate boundaries, pressure or heat from the exsolved gases in the magma, injection of a new batch of magma into an already filled magma chamber, constructive and destructive plate movements, gas release under decompression, thermal contraction from chilling on contact with water, ejection of entrained particles during steam eruptions, amongst others. Like one would guess, volcanoes can cause respiratory illnesses due to inhaled ash that could form glassy cement-like mixtures in the lungs, causes weather and climate change, bring about bad air quality, as gases erupting contains sulfur dioxide, hydrogen chloride, Hydrogen fluoride and hydrogen sulfate, all in disturbing quantities.
But hey, some good news! Volcanic ash provides nutrients to nearby plants. And another! Lava cools and hardens to rock thereby creating new land forms, shaping the world we all live in.
Volcanoes can form as Stratovolcanoes that appear as tall steep mountains, or as shield volcanoes that are flatter and dome- shaped, or as calderas which are large depressions on the ground, and mid-ocean ridges, which are underwater chains of volcanic mountains. How about we talk of UNDER WATER VOLCANOES? It means Volcanic activities happen right under water too. The under water volcanoes are situated two miles below the earths surface. The sea floor and mountains were formed by countless volcanic eruptions. What’s more is that pressure of water around underwater volcanoes is enormous. The water contains metals, hydrogen sulfide, poisonous flammable and corrosive gas that are quite toxic. Yet some organisms such as shrimps, and worms live around it.
Hey! there is MUD VOLCANOES too. Not all volcanoes belch out lava. In the arctic ocean, in ice cold dark waters, there are active mud volcanoes that spew out methane gas and warm mud. The activities of these warm muds, increases the temperature of the sea and warm up water around it.
To imagine that a huge rocky and mountainous land form was once a red hot liquid substance is overwhelming. Next time you hear or see volcanoes erupting, just know that it has travelled several mile journey from within.