Mauna Loa volcano is located on the island of Hawaii with four other volcanoes that make up the island. Loihi is a seamount that is growing just off the coast of Kilauea that is the newest member of the Hawaiian Volcanoes chain. The island sits above the Hawaiian hot spot that feeds the three active Hawaiian volcanoes on the island.
The Hawaiian hot spot is located in the middle of the Pacific Ocean plate that has been there for millions of years. As the Pacific Ocean plate slowly moves northwestward relative to North America and other hot spots beneath the plate the plume of molten rock has created a string of submarine volcanoes that reach from Loihi north all the way to the Aleutian Trench. The Hawaiian-Emperor seamount chain is over 3,600 miles long. The Hawaiian ridge is the southern section where the islands of the Hawaiian chain have formed. They are the only volcanoes that reach above the surface of the ocean in the chain.
Mauna Loa volcano is the second largest volcano on Earth. Recently discovered Tamu Massif is larger but it does not reach the surface of the ocean. Mauna Loa is the largest volcano that is subaerial, which means that part of the volcano lies above the ocean’s surface. Mauna Loa covers about half the surface area of the island of Hawaii. The part of the volcano that makes up the island that people visiting the island walk on the upper part of the volcano and its summit which reaches 13,680 feet (4,170 m).
Mauna Loa covers 2,035 square miles (5,271 sq km) and has erupted between 15,600 to 19,200 cubic miles (65,000 to 80,000 cubic km) of lava that has turned into solid rock. The volcano is so massive the bottom of the volcano has sunk down 5 miles (8 km) beneath the ocean floor. If you add the height of the island plus the height of the volcano from the ocean floor it reaches 30,085 feet (9,170 m). Now add all the lava that forms a bowl shape depression beneath the ocean floor the TRUE height of Mauna Loa volcano is 56,000 feet (17,170 m).
Mauna Loa is one of the most active volcanoes on our planet. It is also considered one of the most dangerous. The volcano has two cycles to its eruptions that are unique to Mauna Loa. The volcano will erupt from its summit for 1,500 to 2,000 years then it switches to fissure eruptions on its flank. Typical of all Hawaiian eruptions they are considered quiet because of the hot fluid basalt lava they erupt. At the start of an eruption lava fountains known as curtains of fire blown into the air along a rift in the volcano that is several kilometers long. Over time the eruption flows from a single volcano vent. Mauna Loa does not erupt as often as Kilauea but it erupts a greater volume of lava during a shorter period of time.
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