|
SHIELD VOLCANO
[appear in the shape of a shield, very large, with a wide base, and often very high, because the wide base can support a larger mountain] |
THE LARGEST TYPE OF VOLCANO. Shield volcanoes are low in quartz and high in magnesium and iron, making them MAFIC on the igneous rock chart. Their lava has a low viscosity [meaning that it flows easily], has a low gas content [since gas can escape more easily from an easy flowing magma type]. Shield volcanoes produce mild eruptions. |
|
COMPOSITE [STRATOVOLCANO] VOLCANO |
Composite volcanoes are the classic volcanic shape, seen in artwork and Hollywood. The magma of a composite volcano is high in quartz, so it is a FELSIC magma. It has a high viscosity [thick, flows poorly] and has an extremely high gas content [gas is trapped easily in thick magma] Composite volcanoes explode with a huge amount of pressure. They are normally caused or found at a subduction zone. |
|
CINDER CONE |
A cinder cone volcano has steep slopes and a large angle of repose. They are usually only 1,000 to 1,5000 ft tall, and produce mild eruptions. An example of a cindercone volcano is in Paricutin, Mexico. [see PARICUTIN, below] |
KRAKATOA |
Birdseye view of Krakatoa's explosion |
1886, Indonesia |
Krakatoa erupted, and created a giant hole on the island. Water immediately rushed to fill the void, and the waves from all sides came together and collided, went sprawling in all directions, causing an ENORMOUS tsunami. Killed 36,000 people, including the people on Krakatoa, as well as others on surrounding islands, killed by the tsunami! Produced the loudest noise ever heard by humans! |
MT PELEE |
A pyroclastic flow after Pelee erupted
|
1902, St Pierre, Martinique |
The mayor of St. Pierre blocked his citizens into the town, thinking that he would receive more votes if more voters were present. Pelee erupted, and only 1 out of the 30,000 inhabitants survived, a prisoner who was being held in an underground cell for murdering a man in a bar under the influence. He was foun 3 days later, burned, after being kept in the cell that reached temperatures of 140 degrees. Traveled with Barnum and Bailey's circus after the incident. |
KILAUEA |
A lava flow from Kilauea
|
Hawaii |
Kilauea is an enormous shield volcano |
MAUNA LOA |
This volcano is so large that its summit is higher than the clouds in the photograph!
|
Hawaii |
The largest shield volcano on Earth! |
ELDFELL |
The small white dot in the foreground of the picture is a house, and Eldfell is the mountain in the back |
1973, Heimaey, Iceland |
Eldfell is known for being a great fishing port on the coast of Iceland, and it has a natural harbor that is great for boats. Eldfell (the volcano) explodes, and lava flows threaten to block the exit of the harbor. The townspeople attempt to stop the flow with buckets of water, and the military comes in with large miliatary hoses to stop the flow. They were successful, and it is the only recorded time in history that humans have stopped a pyroclastic flow! |
MT ST. HELENS |
Mt St. Helens during the colder months! |
1988, Washington, United States |
The state of Washington evacuated people from 20 miles around the base of Mt St. Helens when they sensed an eruption. Harry Truman, an innkeeper on the shores of Spirit Lake, refused to leave his inn at the base. One of the sides of Mt St. Helens collapsed, and it erupted, causing huge lahars! Spirit Lake was buried, as well as Harry Truman. Largest volcanic eruptiont o occur in North America. |
PARICUTIN |
A church that has been buried by lava flows from the 1943 eruption |
1943, Paricutin, Mexico |
One day a corn farmer noticed smoke coming from his field. He ran to the scene and discovered a depression in the field, and a sulphuric odor. A volcano had created in his corn field over night! Over the next 12 years, the volcano continues to build up, reading 1500 ft by 1955 (stops erupting) It erupts and buries the town of Paricutin. The first death due to Paricutin didnt occur until 1957, when citizens got in land disputes and shot eachother. |
LAKE NYOS |
THE Lake Nyos! |
1986, Cameroon, Africa |
Lake Nyos erupted in the middle of the night, and caused a large emission of CARBON DIOXIDE from the actual lake. Since all the people were sleeping, they were all on the floor, low to the ground. The carbon dioxide killed them all in their sleep. |
VESUVIUS |
The remains of Pompeii with Vesuvius in the distance |
Pompeii |
Vesuvius erupted and created a humungous pyroclastic flow, which buried the city of Pompeii and its inhabitants. |
SANTORINI |
View from a mountain on Santorini |
Santorini, Greece |
The explosion of Santorini, a composite volcano, could explain the myth of the lost continent, Atlantis. |
PINATUBO |
An eruption of Pinatubo |
June 15th, 1991, Phillipines |
Eruption of Pinatubo led to the largest evacuation of all time, Clark Airforce base. Most people died of ash, or collapsed roofs. |
SAKURAJIMA |
A city across the water watches as Sakurajima erupts |
Japan |
Sakurajima is the most active volcano, erupting up to 400 times a year |
RAINIER |
A sleeping giant! The calm before the storm; Rainier during the beautiful summer months |
United States |
Mt. Rainier is the most dangerous volcano in the U.S, because it is also the most likely to explode. Located on the Cascade Mountain Range |
NEVADA DEL RUIZ |
A "smoky" view from the top |
Columbia |
23,000 people died in Columbia after Nevada Del Ruiz erupted, due to moist lahars. Composite volcano. |
MT. TAMBORA |
The summit of Tambora above the clouds |
1815, Simbawa, Indonesia |
80,000 people died from starvation! Most fatal volcano in history. Eruption caused "the year without a summer", when it snowed in June and July. |
OLYMPUS MONS |
Olympus Mons from outer space |
Mars |
60,000 ft tall. Olympus Mons is the largest volcano in the solar system. |