Consider the following statements with reference to Volcanoes: Sh...
Volcanoes
Volcanoes are openings in the Earth's surface through which molten rock, ash, and gas can escape. They are classified into different types based on their shape, size, and eruptive behavior.
Shield Volcanoes
Shield volcanoes are broad, gently sloping volcanoes that resemble a warrior's shield. They are not the largest or most explosive of the Earth's volcanoes but are instead characterized by their effusive eruptions that produce lava flows. The Hawaiian volcanoes are the most famous examples of shield volcanoes.
Composite Volcanoes
Composite volcanoes, also known as stratovolcanoes, are steep-sided, cone-shaped volcanoes that are built up by alternating layers of lava flows and other volcanic materials such as ash and rocks. They are the most explosive of the Earth's volcanoes due to the presence of viscous lava that traps gases and builds up pressure before erupting. Examples of composite volcanoes include Mount Fuji in Japan and Mount St. Helens in the United States.
Correct Answer
The statement "Shield Volcanoes are the largest and the most explosive of the earth’s volcanoes" is incorrect as shield volcanoes are not the most explosive of the Earth's volcanoes. The statement "The Hawaiian volcanoes are the most famous examples of Composite Volcanoes" is also incorrect as the Hawaiian volcanoes are examples of shield volcanoes. Therefore, the correct answer is option D, neither 1 nor 2.
Consider the following statements with reference to Volcanoes: Sh...
Shield Volcanoes: Barring the basalt flows, the shield volcanoes are the largest of all the volcanoes on the earth. The Hawaiian volcanoes are the most famous examples of Shield Volcanoes. These volcanoes are mostly made up of basalt, a type of lava that is very fluid when erupted. For this reason, these volcanoes are not steep. They become explosive if somehow water gets into the vent; otherwise, they are characterised by low-explosivity. The upcoming lava moves in the form of a fountain and throws out the cone at the top of the vent and develops into a cinder cone.
So, statement 1 is not correct. Caldera is the most explosive of the earth’s volcanoes. They are usually so explosive that when they erupt they tend to collapse on themselves rather than building any tall structure. The collapsed depressions are called calderas. Their explosiveness indicates that the magma chamber supplying the lava is not only huge but is also in close vicinity. So, statement 2 is not correct. Therefore, the correct answer is d.
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