Geology of Kilauea Volcano

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Halau makes offering to Pele at Kilauea Volcano lookout :Dancers with
Halau Ka Liko Pua O Kalaniakea, under the direction of Kumu Kapua
Dalire-Moe danced and chanted to pay their respects to Pele on April 2,
2008. Volcanic fumes spewed from Halemaumau in the background.
After the halau danced and chanted, they threw all their leis into the
crater, returning them back to the earth
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
1.
2.
3.
4.
5.
Location Map
Shield Volcano
Most active Volcano
Geologic Features
Volcanic Hazards
6. Kilauea's Pu'u O'o vent
erupted in July 1983, sending
a river of lava from Kilauea's
east rift zone
Halema'uma'u as a cloud of ash and sulfur dioxide rushes into the air
March 26, 2008.
Kilauea is Hawaii's youngest volcano and one of the world's most active.
Over 90 percent of Kilauea's surface is covered by lava less than 1,100
years old. In historical time, all of Kilauea's eruptions have occurred
either in or near its summit caldera, or along the east or southwest rift
zones. For the foreseeable future, we can assume that active vents will be
limited to these areas.
Kilauea's daily lava production averages between 300,000 to 600,000
square meters (358,000 to 717,000 square yards). Over the past two
decades the eruption has added more than 540 acres (219 hectares) of
new land to the big island of Hawaii's south shore.
March 6, 2008 Lava completed its trip down the slopes of Kilauea
volcano and has begun flowing into the ocean in the remote Puna
coastline to see Madame Pele's handiwork. Laze, lava haze and steamy
vapors from the sea are hazardous.
March 6, 2008 Lava Flow
New vent in Halema'uma'u crater
3/27/2008.
The Three V’s of Volcanology:
Viscosity, Volatiles, Volume
Kilauea – Explosive Eruption Event of 1790
• Kilauea killer pyroclastic events
– Hawaii’s King Keoua’s army passing through
Kilauea area was stopped by eruptions and split
into three groups to escape area
– Base surge overtook middle group, killing all 80
• Explosion column burst upward as dense basal
cloud swept downhill
• Cloud of hot water and gases sometimes with
magma fragments
The island of Hawaii is divided into zones according to the degree
of hazard from lava flows. Zone 1 is the area of the greatest
hazard, Zone 9 of the least.
The current vent at Kilauea consists of a small lava lake about 100
meters (330 feet) across that produces a relatively small thermal hot spot.
From this vent, lava is transported 10 kilometers (6 miles) in lava tubes
to the Pacific Ocean where large steam plumes are generated by the
interaction between the hot lava and the ocean
Kilauea Volcano, Hawai`i
The eruption of Kilauea Volcano that began in 1983 continues at the
cinder-and-spatter cone of Pu`u `O`o (high point on skyline). Lava
erupting from the cone flows through a tube system down Pulama Pali
about 11 km to the sea (lower left). Oct 11, 2002, HVO
Kilauea Volcanoe’s pathway of molten rock during the eruption of Pu`u
`O`o, located on the east rift zone about 20 km from the
caldera.(Modified after J. Johnson, 1984-2004)
4/23/90
6/9/90
In June 1990, Walter's Kalapana Store and Drive Inn (sign in photo
above) was burned and covered by lava in early June as flows moved
relentlessly through the Kalapana area. During this difficult period,
scientists of the USGS Hawaiian Volcano Observatory provided detailed
information on lava movement to the Hawai`i County Civil Defense,
which made decisions regarding evacuation, road closures, and safe
vantage points for residents and visitors.
Oblique map of Kilauea Volcano: Most lava flows erupted from Kilauea
since A.D. 1790 (shown in red) originated from the east rift zone, which
extends 34 miles (55 km) from the summit caldera to the eastern tip of the
Island of Hawai`i. Lava flows from the present eruption (shown in
yellow) span more than 9 miles (15 km) along the coast. USGS
During the first 3 1/2 years of the eruption, fallout from lava fountains at Pu`u `O`o built a
cinder-and-spatter cone 835 feet (255m) high, more than twice as high as any other cone on
Kilauea's east rift zone. Cone growth ceased after the activity shifted to Kupaianaha in mid-1986.
When the eruption returned to Pu`u `O`o in 1992, lava flows from flank vents built a shield
against the west flank of the cone (left). in 1993, collapse pits appeared on the west flank of Pu`u
`O`o as subsidence over the flank vents undermined the cone. When the floor dropped in January
1997, the weakened flank also failed, leaving the prominent "west gap." Note growth of the
shield (right). USGS photos by Tari Mattox and Christina Heliker
Hawaii, 6/1/2001 NASA: The black areas on the island (in this scene)
that resemble a pair of sun-baked palm fronds are hardened lava flows
formed by the active Mauna Loa Volcano. Just to the north of Mauna Loa
is the dormant grayish Mauna Kea Volcano, which hasn’t erupted in an
estimated 3,500 years. A thin greyish plume of smoke is visible near the
island’s southeastern shore, rising from Kilauea—the most active
volcano on Earth. Heavy rainfall and fertile volcanic soil have given rise
to Hawaii’s lush tropical forests, which appear as solid dark green areas
in the image. The light green, patchy areas near the coasts are likely
sugar cane plantations, pineapple farms, and human settlementsThe black
areas on the island (in this scene) that resemble a pair of sun-baked palm
fronds are hardened lava flows formed by the active Mauna Loa Volcano.
Just to the north of Mauna Loa is the dormant grayish Mauna Kea
Volcano, which hasn’t erupted in an estimated 3,500 years. A thin greyish
plume of smoke is visible near the island’s southeastern shore, rising
from Kilauea—the most active volcano on Earth. Heavy rainfall and
fertile volcanic soil have given rise to Hawaii’s lush tropical forests,
which appear as solid dark green areas in the image. The light green,
Kilauea erption strated on Jan 3, 1983, and
continues on presently. Pu'u O'o is the
longest-lived eruption in the 200-year record
of the Kilauea Volcano. Lava production rates
are hard to determine, but scientists estimate
that Pu'u O'o produces between 300,000 and
600,000 cubic meters of lava per day. In fact,
Pu'u O'o's broad field of lava flows have
buried more than 130 square km of Kilauea's
southern flank and have added more than 300
hectares (860 acres) of new land to the island.
The bottom image is a false-color composite
using the ETM+ infrared detectors (channels
6, 7, and 5), which are sensitive to heat. The
red regions show solidified rock from
previous lava flows. Notice the thin yellow
ribbon snaking toward the ocean away from
where the steam is venting. This yellow
ribbon shows the location of a river of molten
rock running beneath the surface--called a
lava tube. Such areas are particularly
dangerous to hikers and explorers as these
tubes may collapse without warning
Lava Tubes on Mt. Kilauea
Kilauea's caldera is located toward
the northwestern corner (upper
left) of the image. The brown hues
show volcanic rock, while dark
browns and black show relatively
recent lava flows that have cooled
and solidified into rock. The green
hues show forest canopy, white
pixels are clouds, and the blue to
the south and east is the open
Pacific Ocean. Notice the thin
plume of steam streaming from
one of Pu'u O'o's active lava tubes.
Kilauea 1994 Space Radar Image Map:
Deformation map of the south flank of Kilauea
volcano on the big island of Hawaii, centered at
19.5 degrees north latitude and 155.25 degrees
west longitude. The south flank of the Kilauea
volcano is among the most rapidly deforming
terrains on Earth. Several regions show motions
over the six-month time period. Most obvious is at
the base of Hilina Pali, where 10 centimeters (4
inches) or more of crustal deformation can be seen
in a concentrated area near the coastline. On a
more localized scale, the currently active Pu'u O'o
summit also shows about 10 centimeters (4
inches) of change near the vent area. Finally, there
are indications of additional movement along the
upper southwest rift zone, just below the Kilauea
caldera in the image. Deformation of the south
flank is believed to be the result of movements
along faults deep beneath the surface of the
volcano, as well as injections of magma, or
molten rock, into the volcano's "plumbing"
system. Detection of ground motions by GPS.
Volcanic gases escape from vents on the crater floor of the Pu`u `O`o
cone, located 12 miles (19 km) east of the summit of Kilauea Volcano.
Since 1987, repeated collapses of the cone have resulted in a crater more
than 1,300 feet (400 m) long. The crater floor is 40 feet (13 m) below the
lowest part of the rim. In the distance (upper left), steam plumes rise
where lava flows pour into the sea, about 7 miles (11 km) south of Pu`u
The Hawaiian archipelago, the most isolated island group of comparable
size and topographic diversity on Earth, is about 4,000 kilometers from
the nearest continent and 3,200 kilometers from the nearest high-island
group (the Marquesas Islands of French Polynesia). The state of Hawaii
consists of 132 islands, reefs, and shoals stretching 2,400 kilometers in a
northwest-southeast direction between latitudes 28°N and 19°N (Price
1983). The eight major high islands, located at the southeast end of the
chain (Fig. 2), make up more than 99% of the total land area. The
youngest island, Hawaii, has an area of more than 10,000 square
kilometers (63% of the total area of the state) and has elevations of more
than 4,000 meters. The island of Hawaii has five volcanoes, two of
which are highly active. These islands are part of a longer chain that was
produced during at least a 43-million-year period by the northwestward
movement of the ocean floor over a hot spot below the Earth's crust (Fig.
3). The oldest rocks of the eight high islands range from 420,000 years
old (the island of Hawaii) to about 5 million years old (Kauai). The
relatively tiny eroded and submerged islands and reefs extending to the
northwest are remnants of high islands that existed millions of years ago
Kilauea volcano, which overlaps the east flank of the massive Mauna Loa shield
volcano, has been Hawaii's most active volcano during historical time. Eruptions
of Kilauea are prominent in Polynesian legends; written documentation extending
back to only 1820 records frequent summit and flank lava flow eruptions that were
interspersed with periods of long-term lava lake activity that lasted until 1924 at
Halemaumau crater, within the summit caldera. The 3 x 5 km caldera was formed
in several stages about 1500 years ago and during the 18th century; eruptions
have also originated from the lengthy East and SW rift zones, which extend to the
sea on both sides of the volcano. About 90% of the surface of the basaltic shield
volcano is formed of lava flows less than about 1100 years old; 70% of the
volcano's surface is younger than 600 years. A longterm eruption from the East
rift zone that began in 1983 has produced lava flows covering more than 100 sq
km, destroying nearly 200 houses and adding new coastline to the island.
The Pu`u `O`o-Kupaianaha eruption of Kilauea (1983-present) is the
volcano’s longest rift-zone eruption in more than 600 years. Lava flows
have buried 43 square miles (111 km2) of the volcano and added 544
acres (220 ha) to the Island of Hawai`i.
Pu`u `O`o-Kupaianaha Eruption Statistics, 1983 to 2003
Lava flows Area covered: 42.6 square miles (110.4 km3
)New land: 544 acres (220 ha)
Volume: 0.6 cubic miles (2.3 km3)
Thickness along coast: 33-115 feet (10-35 m)
Highway covered: 8 miles (13 km)
Structures destroyed: 189
Pu`u `O`o Maximum height, 1987: 835 feet (255 m)
Height (September 2002): 613 feet (187 m)
Crater size: 820 x 1, 312 feet (250 x 400 m)
Height of west flank shield: 260 feet (80 m)
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.
Kamapua`a, a jilted suitor of Pele, is said to have built a house of ferns over
Halema`uma`u to keep Pele from escaping her home and causing eruptions. The ploy
failed.
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 BP
Hawaiian Volcano Stage: Shield-forming stage
Much of Earth's internal heat comes from the radioactive decay of heavy
elements.
showing that a large portion of the volcano has shifted seaward more
than 5 meters since 1970. These motions may presage a catastrophic
collapse of Kilauea into the sea
Mount Rainier has 25 times as much ice as Mount St. Helens did. It can
cause catastrophic debris slides known as lahars, which in the past have
reached Puget Sound. The cutaway shows how infiltrating water is
heated; it melts glacier bottoms and, with hydrogen sulfide added, turns
rock to clay.
The chronology of the first 2 decades of the Pu‘u ‘Ö‘öKüpaianaha eruption lacks a final chapter. Our ability to
predict the onset of a Kïlauea eruption far exceeds our ability
to predict its end. In the early years of this eruption, we
speculated that a large earthquake might disrupt the rift-zone
plumbing and bring the activity to a close. Although the
eruption has not yet been tested by an M>7 earthquake, the
activity has proven remarkably impervious to lesser tectonic
and magmatic events.
In its first decade, the eruption weathered the M6.6
Ka‘öiki earthquake of 1983 and the M6.1 Kalapana earthquake
of 1989. In March–April 1984, Mauna Loa erupted for
3 weeks, while at Pu‘u ‘Ö‘ö, episode 17 occurred on schedule,
and the two volcanoes erupted simultaneously (Wolfe and
others, 1988). In 1997, Pu‘u ‘Ö‘ö revived after substantial
edifice collapse and a prolonged hiatus in activity. Thus far,
the Pu‘u ‘Ö‘ö-Küpaianaha eruption has withstood all of these
events and shows no sign of faltering; the eruption continues
Steam is formed from rainwater dripping down the crack onto the hot
rocks of the volcano. Some plants are thriving in the mist.
Kilauea currently emits over 2,000 tons of sulfur dioxide each day.
Hawaii’s trade winds disperse these volcanic gases however it’s not wise
to get too close to these concentrated fumes
Volcanic Emissions
Wet deposition, Gases and Vapors
Water H2O (70%)
Carbondioxide CO2 (15%)
N2 and nitrogen compounds (5%)
sulfur compounds (H2S, SO4,
SO2, etc.) (5%)
minor amounts of Cl, H2, Ar, etc.
NO free oxygen
Between 100 and 2000 metric tons
of sulfur dioxide (SO2) are
released per day from Kilauea. The
rain is so acidic that a desert has
formed downwind from the
summit of the volcano.
SO2, 2002
Carbon dioxide is released when magma rises on its
way to the surface. Our studies here at Kilauea show
that the eruption discharges between 8,000 and 30,000
metric tonnes of CO2 into the atmosphere each day.
Actively erupting volcanoes release much more CO2
than sleeping ones do.
Gas studies at volcanoes worldwide have helped
volcanologists tally up a global volcanic CO2 budget
in the same way that nations around the globe have
cooperated to determine how much CO2 is released by
human activity through the burning of fossil fuels.
Studies show that globally, volcanoes on land and
under the sea release a total of about 200 million
tonnes of CO2 annually.
Side Note: British Airways Flight 9
• 1982 flight from Kuala Lumpur, Malaysia to
Perth, Australia lost all four engines at 37,000 feet
• Plane descended to 12,000 feet before engines
started again
• Emergency landing in Jakarta
• Plane had flown through eruption cloud of hot
volcanic ash and pyroclastic debris from Mount
Galunggung
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