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Which of the following is the world’s highest active volcano?
Cotopaxi's "highest" status is often debated among geographers, as it depends on how "active" is defined. However, in most competitive exams, Cotopaxi is the standard answer because of its classic volcanic shape and its very clear, documented history of frequent eruptions. Unlike other higher peaksRead more
Cotopaxi’s “highest” status is often debated among geographers, as it depends on how “active” is defined. However, in most competitive exams, Cotopaxi is the standard answer because of its classic volcanic shape and its very clear, documented history of frequent eruptions. Unlike other higher peaks that may be dormant or show only minor steam activity, Cotopaxi has produced devastating lahars and ash clouds in recent centuries. Its height, combined with its dangerous levels of activity, makes it one of the most monitored mountains in the South American Andes.
See lessIn which continent is Mount Erebus volcano located? (A) Africa (B) Europe (C) Asia (D) Antarctica
Erebus stands over 3,700 meters high and has been continuously active since at least 1972. It is famous for its "lava lake," which consists of rare molten phonolite rock. Because the volcano is located near major research stations like McMurdo (USA) and Scott Base (New Zealand), it is one of the mosRead more
Erebus stands over 3,700 meters high and has been continuously active since at least 1972. It is famous for its “lava lake,” which consists of rare molten phonolite rock. Because the volcano is located near major research stations like McMurdo (USA) and Scott Base (New Zealand), it is one of the most thoroughly studied volcanoes in the polar regions. Despite the freezing temperatures of Antarctica, the heat from Erebus creates unique “ice towers” around its steam vents, where warm volcanic gas freezes into giant hollow chimneys as it hits the sub-zero air.
See lessWhich of the following is a dormant volcano? (A) Krakatoa (B) Chimborazo (C) Mauna Loa (D) Stromboli
The term "dormant" can be tricky. Krakatoa was considered "extinct" or "long-dormant" by the people living near it in the 1800s because it hadn't erupted for over 200 years. Its sudden awakening in 1883 proved how dangerous dormant volcanoes can be. Today, the site remains very active. In contrast,Read more
The term “dormant” can be tricky. Krakatoa was considered “extinct” or “long-dormant” by the people living near it in the 1800s because it hadn’t erupted for over 200 years. Its sudden awakening in 1883 proved how dangerous dormant volcanoes can be. Today, the site remains very active. In contrast, Stromboli and Mauna Loa are “constantly active,” and Chimborazo is “extinct” (it hasn’t erupted in over 1,000 years). Krakatoa serves as a reminder that “dormancy” is simply a quiet phase in the life of a very dangerous, active volcanic system.
See lessThe ‘Lehmann Discontinuity’ marks the boundary between which two layers?
Before Lehmann, scientists thought the entire core was liquid. She noticed that some P-waves were showing up in the "shadow zone" where they shouldn't be. She theorized that these waves were bouncing off a solid inner sphere. Her discovery changed our entire model of the Earth's interior. We now knoRead more
Before Lehmann, scientists thought the entire core was liquid. She noticed that some P-waves were showing up in the “shadow zone” where they shouldn’t be. She theorized that these waves were bouncing off a solid inner sphere. Her discovery changed our entire model of the Earth’s interior. We now know the inner core is a solid ball of iron and nickel, kept solid by immense pressure despite temperatures exceeding 5,000°C. This solid inner core is essential for the Earth’s rotation and the stabilization of our magnetic field.
See lessWhich region experiences ‘Megathrust’ earthquakes? (A) Mid-Atlantic Ridge (B) East African Rift (C) Subduction Zones (D) San Andreas Fault
Because the contact area between two subducting plates is massive (hundreds of kilometers long and wide), it can store an incredible amount of elastic energy. When this "megathrust" finally slips, the energy release is equivalent to thousands of atomic bombs. All of the top 10 largest earthquakes inRead more
Because the contact area between two subducting plates is massive (hundreds of kilometers long and wide), it can store an incredible amount of elastic energy. When this “megathrust” finally slips, the energy release is equivalent to thousands of atomic bombs. All of the top 10 largest earthquakes in recorded history, including the 1960 Chile (9.5) and 2011 Japan (9.1) quakes, were megathrust events. These boundaries are also unique because they involve vertical seafloor movement, making them the primary source of trans-oceanic tsunamis.
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