1. Mahukona Loihi Volcanoes of the Island of Hawaii Seven Shield Volcanoes Types of Volcanoes Descriptions and ImagesEruption Update

2. GG103 Nasir Gadzar How and why volcanoes erupt

3. 5 Shield Volcanoes 2 Submarine cones

5. Pacific Ocean Red – recent volcanism on the ocean floor Green – Hawaiian islands Hawaiian Islands

7. Island of Hawaii The subaerial (rocky, above sea level) portion of the Island of Hawaii is made of five volcanoes. From oldest to youngest, they are Kohala, Mauna Kea, Hualalai, Mauna Loa, and Kilauea. Each volcano can be recognized by its size, shape, and physical features. Two other volcanoes, Mahukona and Loihi, add to the submarine base of the Island. Mahukona Pacific Ocean

8. Volcanoes of the Island of Hawaii, elevation, area.

9. Volcanoes are classified as: Active - These are erupting or keep erupting. Kilauea Dormant - These are not erupting but could at any time. Mauna Kea Extinct - These volcanoes are no longer active and do not erupt. Diamond Head Crater

10. ~1500 volcanoes are potentially actives on Earth ~ 70 are currently in eruption ~ 10% of the human population is directly exposed to volcanic risk. Several large cities are located close to an active or dormant volcano

11. Cinder Cones - Cinder cones are the simplest type of volcano. They are built from particles and blobs of congealed lava ejected from a single vent. As the gas- charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as cinders around the vent to form a circular or oval cone. Most cinder cones have a bowl-shaped crater at the summit and rarely rise more than a thousand feet or so above their surroundings. Cinder cones are numerous in Hawaii as well as throughout other volcanic terrains of the world.

12. Shields - Another easily recognized volcano which is familiar is the Shield volcano. This type of volcano can be hundreds of miles across and many tens of thousands of feet high. The individual islands of the state of Hawaii are simply large shield volcanoes. Mauna Loa, a shield volcano on the island of Hawaii, is the largest single mountain in the world, rising over 30,000 feet above the ocean floor and reaching almost 100 miles across at its base. Shield volcanoes have low slopes and consist almost entirely of frozen lavas

13. The animation shows the steps in the formation of a caldera. The volcano usually shows signs of erupting by producing earthquakes as the magma rises in the volcano.

14. Calderas - Calderas, are simply circular depressions, are found on the summits of many volcanoes. "Giant" calderas are the largest of these: huge craters up to many tens of miles across. Giant Calderas form by collapse (see animation) in gigantic eruptions that spew volcanic rocks out hundreds or even a thousand miles in all directions. Sometimes the calderas are so filled with lava and volcanic ash that there is no recognizable depression at all.

15. After a huge ejection of lava there may be no magma left in the chamber to fill the conduit and crater. When this happens there is a hollow space under the summit of the mountain where the magma used to be. The top of the mountain then collapses creating a caldera.

16. The caldera may fill with water creating a lake.

19. Shield Volcanoes of the Hawaiian Islands Shield Volcanoes are enormous features built up only from layers of lava. They produce lots of A’a and Pahohoe lava flows but they tend not to erupt violently. 250 kilometer 10,000m Basaltic Lava Flow Topographic Profile of Mauna Loa

20. Hawaiian Islands Palaeogeographical Location of the various islands over the active volcanic activity (hotspot red circle) at different times

21. Kilauea magma hiding from volcano scientists: Scientists at Kilauea Volcano are pondering the big question: Where is 250,000 cubic yards of magma going if it's not flowing each day to the Pu'u 'O'o eruption? Magma that forced its way into the upper East Rift Zone and caused hundreds of earthquakes finally cracked the surface.

23. A tour boat had a sea view of lava from Kilauea flowing into the ocean. Michael Marlin

24. Lava flows from Kilauea March 12, 2008

25. An abandoned pickup truck is engulfed in flames after lava from Kilauea came into contact with it.

26. A backyard swimming pool in the Royal Gardens area of the Big Island that was once filled with water is now filled with lava from Kilauea.

27. Stages of Growth of Volcanoes in Hawaii, 500,000 years ago

28. In order of growth, the volcanoes that make the island and its submarine base are Mahukona, Kohala, Mauna Kea, Hualalai, Mauna Loa, Kilauea, and Loihi. Mahukona, Kohala, Mauna Kea, and Hualalai have completed their shield-building stage. Mahukona slides into the sea

29. The island has grown at an average rate of 0.008 mi2/yr (5 acres; 0.02 km2/yr) for the past 600,000 years. It is estimated that 600,000 years was required for each volcano to grow from the ocean floor to the end of its shield building stage

30. Kohala Shield Volcano – Extinct volcano Most Recent Eruption(s) About 120,000 years ago Number of Historical Eruptions none Oldest Dated Rocks About 460,000 years before present 46 万年間 Estimated Age of Kohala Emerged above sea level before 500,000 years ago Hawaiian Volcano Stage Transition between postshield and erosional stage Location 20.08 N 155.70 W Elev. Above Sea Level 1,670 m 5,480 ft Area 606 km2 235 mi2 (5.8% of Hawai`i) Volume 14,000 km3, 3,400 cu mi3

31. Mauna Kea – tallest volcanoe Most Recent Eruption(s) At least 7 separate vents erupted between about 6,000 and 4,000 years ago Number of Historical Eruptions none Oldest Dated Rocks 237,000 ± 31,000 years before present 23 万年間 Estimated Age of Mauna Kea About 1 million years, 100 万年間 Volcano Stage Post-shield Stage (transition from shield stage to post-shield occurred before about 200,000 to 250,000 years ago) Location 19.82 N 155.47 W Elev. Above Sea Level 4,205 m 13,796 ft Area 2,380 km2 920 mi2 (22.8% of Hawai`i) Volume >30,000 km3 >7,200 mi3

32. Location 19.475 N 155.608 W Elev. Above Sea Level 4,170 m 13,680 ft Area 5,271 km2 2,035 mi2 (50.5% of Hawai`i) Volume 80,000 km3 19,000 mi3 Mauna Loa Most Recent Eruption, March 24-April 15, 1984 Summit Caldera Name: Moku`aweoweo, "Moku" refers to a coastal land section or islet; "`aweoweo" is a type of red Hawaiian fish. Literal translation is fish section Dimension: 3 x 5 km, elongated northeast- southwest Depth: 183 m deep Age: estimated to have collapsed 600-750 years ago Oldest Dated Rocks Between 100,000 and 200,000 years ago Estimated Age of Earliest Subaerial Eruptions About 400,000 years ago Estimated Age of First Eruption of Mauna Loa Between 1,000,000 and 700,000 years before present Hawaiian Volcano Stage: Shield-forming stage

33. Location 19.69 N 155.87 W Elev. Above Sea Level 2,521 m 8,271 ft Area 751 km2 290 mi2 (7.2% of Hawaii) Volume 12,400 km3 2,975 mi3 Hualalai: Most Recent Eruption(s) 1800 and 1801

34. Hawaiian Meaning The Hawaiian name "Kilauea" means "spewing" or "much spreading," apparently in reference to the lava flows that it erupts. Most Recent Eruption Continuous since January 3, 1983 Number of Historical Eruptions 61, not counting the continuous lava-lake activity in Halema`uma`u crater Summit Caldera The caldera itself has no Hawaiian name other than Kilauea but houses the famous crater, Halema`uma`u; "hale" is a house, "ma`uma`u" a type of fern. Dimension: 6 x 6 km (outermost faults), 3 x 5 km (main depression) Depth: 165 m deep Age: probably several incremental collapses 500-210 years ago Oldest Dated Rocks 23,000 years old Estimated Age of Earliest Subaerial Eruptions 50,000-100,000 years Estimated Age of First Eruption of Kilauea 300,000-600,000 years before present Hawaiian Volcano Stage Shield-forming stage Location 19.425 N 155.292 W Elev. Above Sea Level 1,277 m 4,190 ft Area 1,430 km2 552 mi2 (13.7% of Hawai`i) Volume 25,000-35,000 km3 6,000-8,500 mi3

35. Loihi Seamount depth = 969 meters will reach surface in about 30,000 years

36. Mahukona Loihi

37. Volcanic gas escapes from a vent in the Halemaumau Crater near the Jaggar Museum inside Hawaii Volcanoes National Park. AP Photo/Marco Garcia March 19, 2008 Explosive eruption in Halema`uma`u Crater, Kilauea Volcano, is first since 1924

38. The explosion scattered debris over an area of about 75 acres (30 hectares), covering a portion of Crater Rim Drive and damaging the Halema‘uma‘u overlook. Rocks ejected by yesterday’s explosion at Kilauea volcano dug impact craters when they hit. Finer-grained material was blown away during the impact. Boulders and smaller rocks were scattered over a large area of Hawaii Volcanoes National Park, but no one was injured. March 19,2008.

39. Explosive eruptions at Kilauea are thought to be caused when water comes into contact with hot or molten rock (magma) and flashes into steam. In 1924, this happened after the level of the lava lake in Halema'uma'u Crater dropped below the water table. The walls of the crater then collapsed and blocked the opening down which the lava had drained, allowing steam pressure to build up and cause violent explosions. Kilauea: an explosive volcano in Hawai`i

40. Many of Kilauea's pre-1924 explosive eruptions that produced significant ash deposits probably happened when the volcano's summit crater was so deep that its floor was below the water table, letting ground water seep in to form a lake. Whenever magma erupted into the lake water, violent explosions of steam and volcanic gases resulted, fragmenting the magma into tiny ash particles and driving fast-moving, extremely hot ash-laden steam clouds (pyroclastic surges) out of the crater.

41. Kilauea eruption blasts rocks across landscape March 19, 2008. The most recent explosive eruptions before March 19, 2008 were in 1924 and were much bigger than the latest event. Those explosions killed a photographer, who ventured too close and was hit by falling rocks and hot mud. This explosive eruption at Kilauea on May 22, 1924, the cloud was 2 miles high and still rising. Geologists now believe such explosions were common in the past

42. Rocks litter the area around a wooden fence at the Kilauea volcano overlook. The fence was heavily damaged yesterday in the first explosive eruption at Kilauea volcano in almost a century.

43. The largest boulder to be blasted out of Halemaumau Caldera was almost about 3› feet wide. It landed on the steel cable of the barrier adjacent to the trail next to the Halemaumau Overlook. The recent increase in hydrothermal or gas sources had forced the explosive eruption, the first since May 1924. No lava was found in the area.

44. A near vertical view looks down into the explosion crater. The crater is estimated at roughly 100 feet across.

45. KAMEHAMEHA'S VOLCANIC VICTORY The most significant Kilauea eruption ever documented may have altered Hawai'i's history, according to records at the Hawaiian Volcano Observatory. Kamehameha I, before becoming king and uniting the Islands, was locked in an indecisive war with his rival, Keoua. In 1790, a sudden eruption of searingly hot ash and gas exploded out of Kilauea as a large group of Keoua's warriors and their families passed nearby. At least 80 and perhaps hundreds of people were killed in the deadliest historical eruption to occur in what is now the United States. That disaster helped tip the rivalry in Kamehameha's favor.

46. Pu'u 'O'o on Kilauea's East Rift Zone has been producing about 2,000 metric tons of sulfur dioxide a day for years, but only about 200 tons per day were being released at Halema'uma'u at the summit. That changed late last year when sulfur dioxide emissions from the summit began to climb, and by March 13 had reached record levels of 2,000 tons a day as a new vent opened in the wall of the crater.

47. Debris avalanche Debris avalanches are moving masses of rock, soil and snow that occur when the flank of a mountain or volcano collapses and slides downslope. As the moving debris rushes down a volcano and into river valleys, it incorporates water, snow, trees, bridges, buildings, and anything else in the way. Debris avalanches may travel several kilometers before coming to rest, or they may transform into more water-rich lahars, which travel many tens of kilometers downstream

49. Composition of Hawaiian Volcanoes Igneous Rock The term ``igneous'' comes from the Latin word ignis or ``fire''. Igneous rocks are rocks which form from cooling magma or lava. Magma Molten or partially molten rock material and dissolved gases. Magma is molten rock beneath Earth's surface. Lava Molten or partially molten rock material and dissolved gases. Lava is molten rock which has erupted at Earth's surface.

50. Volcanic steam was rising yesterday from the MLK vent that has deepened on Kilauea

51. Hawaii Volcanoes National Park firefighter Sean Grossman, with hose, filled a 5,000-gallon "frog pond" in the park June 21, 2007. The plastic pool was one of five set up by the park to have water ready in case fire flares up from lava flows

52. Volcanic gases and vapors produce VOG - Volcanic fog, LAZE- Lava haze, and acid rain. These air pollutants cause health related problems, water pollution and damage to crops. When sulfur dioxide concentrations greater than 1 ppm (equal to 1,000 parts per billion) are measured, then the volcanic air pollution is common.

53. Slump fissure at edge of Alae crater has split Chain of Craters Road. Kilauea east rift. Hawaii Volcanoes National Park.

54. Giant landslides surrounding the Hawaiian Islands are among the largest known on Earth, and most have occurred within the past four million years. The youngest is thought to have occurred only one hundred thousand years ago, and there is evidence today that large blocks of land on the island of Hawaii are beginning to slide, generating large earthquakes in the process. Each slide has resulted in huge land losses to the islands and resulted in large waves that have carried rocks and sediments as high as 1000 ft above sea level. The giant Hawaiian landslides are important to study because, although they occur infrequently, they have potential for enormous loss of life, property, and resources. Much of the existing topography in Hawaii, both on land and on the seafloor, owes its origin to these landslides,

55. Kilauea has been erupting nearly continuously since Jan. 3, 1983, sending lava from the Pu'u O'o cone through a system of tubes to the ocean, where it forms new land over time. In Hawaiian tradition, Kilauea is home to Pele, the volcano goddess. Lava is said to be her physical representation

56. Kilauea Volcano: 'Something's got to give' June 19, 2007 Watch Video at Honolulu Advertiser : Kilauea lava flows putting on showy display What to know about Kilauea Kilauea's recent activity hints at eruption patternKilauea lava flows putting on showy display What to know about Kilauea Kilauea's recent activity hints at eruption pattern Magma pumping into Kilauea volcano's upper East Rift Zone has buried under lava or scorched nearly seven acres of rainforest, with heat and gases wilting and sickening trees, ferns and other plants around two large cracks that opened this week as the rift expanded Magma Chamber is half filled….

57. Interior Tube (After Harter & Harter, 1979)

58. Surface Trench (After Harter & Harter, 1979)

59. Semi Trench (After Harter & Harter, 1979)

60. True Trench (After Harter & Harter, 1979)

61. Rift Tube - Pre-Flow (After Macdonald, 1965)

62. Rift Tube - Flow 1 (After Macdonald, 1965)

63. Rift Tube - Flow 2 (After Macdonald, 1965)

64. Rift Tube - Flow 3 (After Macdonald, 1965)

65. Rift Tube - Flow 4 (After Macdonald, 1965)

66. Rift Tube - Flow 5 (After Macdonald, 1965)

67. Volcanic Lava Tube Forms

70. Kilauea "skylight" — April 23, 2008 - where a roof section of a lava tube collapsed — and then poured into the skylight, producing a brief surface flow on its way downslope to the ocean.

71. Water Fills Tube

72. Lava flowing underground created this _____ _____, large enough to walk through. lavatube

74. Volcanoes Review: Fast-moving clouds of gas, ash, and other tephra are called ____________ _ Large, rounded tephra are called __________. Iceland and Hawaii have ______ volcanoes. A wall-shaped igneous intrusion is a ______________. dike pyroclastic f lows volcanic bombs shield

75. There are three types of volcanic cones: ______ – explosive eruptions, small but steep slopes, pyroclastics _______ – nonexplosive eruptions, fluid basaltic lava, gentle broad slopes _________ – alternating between lava and pyroclastics, explosive and non-explosive eruptions, steep and tall towering Cinder cones Shield Composite

76. Kilauea on Hawaii is a good example of a _______ volcano, with some explosive eruptions and less viscous lava. shield