What type of lava flow does Kilauea have?
Kilauea is a basaltic shield volcano, erupting a type of basalt known as tholeiite. This type of lava is the dominant extrusive during the shield building (the main stage) of hawaiian volcanism and is the dominant basalt type erupted on Earth.
What is pahoehoe lava flow?
“Pahoehoe” is a Hawaiian word used to describe a lava flow with a smooth, ropy surface. Pahoehoe flows advance slowly, with small amounts of lava squeezing out of a cooler crust. Pahoehoe flows can exhibit all kinds of different shapes as they form and cool. These are sometimes called “lava sculpture.”
How does the lava from a stratovolcano flow?
A stratovolcano is a tall, conical volcano composed of one layer of hardened lava, tephra, and volcanic ash. These volcanoes are characterized by a steep profile and periodic, explosive eruptions. The lava that flows from them is highly viscous, and cools and hardens before spreading very far.
What is basaltic lava flow?
Because of basalt’s low silica content, it has a low viscosity (resistance to flow). Therefore, basaltic lava can flow quickly and easily move >20 km from a vent. The low viscosity typically allows volcanic gases to escape without generating enormous eruption columns.
What type of lava flows the fastest?
PAHOEHOE – has a shiny, smooth, glassy surface. It tends to be more fluid (lower viscosity), hence flows more quickly and produces thinner flows (typically 1-3 m).
Is pahoehoe faster than aa?
Pahoehoe lava flow is usually at least 10 times slower than typical aa lava flow5. Higher effusion rate results in lava flow being shattered which is how the rubbly and clinkery aa lava surface forms.
What type of lava erupts from stratovolcanoes?
The lava flowing from stratovolcanoes typically cools and hardens before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high-to-intermediate levels of silica (as in rhyolite, dacite, or andesite), with lesser amounts of less-viscous mafic magma.
What type of lava flow does a stratovolcano have?
Steep, conical volcanoes built by the eruption of viscous lava flows, tephra, and pyroclastic flows, are called stratovolcanoes. Usually constructed over a period of tens to hundreds of thousands of years, stratovolcanoes may erupt a variety of magma types, including basalt, andesite, dacite, and rhyolite.
Is basaltic magma high in gas?
Basaltic magma — SiO2 45-55 wt%, high in Fe, Mg, Ca, low in K, Na. Andesitic magma — SiO2 55-65 wt%, intermediate. in Fe, Mg, Ca, Na, K….Viscosity of Magmas.
| Summary Table | Solidified Rock | Basalt |
|---|---|---|
| Chemical Composition | 45-55 SiO2 %, high in Fe, Mg, Ca, low in K, Na | |
| Temperature | 1000 – 1200 oC | |
| Viscosity | Low | |
| Gas Content | Low |
How far can basaltic lava flow?
Fluid basalt flows can extend tens of kilometers from an erupting vent. The leading edges of basalt flows can travel as fast as 10 km/h (6 mph) on steep slopes but they typically advance less than 1 km/h (0.27 m/s or about 1 ft/s) on gentle slopes.
Which are types of eruptions produce pahoehoe lava?
The style of a volcanic eruption depends on magma viscosity.
Is pahoehoe lava only found in Hawaii?
ʻAʻā translates into “stony rough lava”, but also to “burn, blaze, glow” or “fire”. Pāhoehoe means “smooth, unbroken lava”. Pahoehoe lava partially covers A’a lava in the Hawaii Volcanoes National Park.
What kind of eruption produces pahoehoe and AA?
Two types of lava flows, pahoehoe and aa, are different textural forms of otherwise identical lava. The smooth-textured pahoehoe lavas (left) are formed by stable upwelling of gas-poor lava, whereas the hackly-surfaced aa flows are produced during eruptions with high lava fountaining of gas-rich magma.
Does Kilauea have pahoehoe or AAA lava?
LAVA VARIETIES – A’A / PAHOEHOE – KILAUEA VOLCANO HAWAII For those of you looking for more technically details: the difference between the two flows is governed by the relative shear-strain rate and viscosity of the flow (Kilburn 1981), or between applied stress and deformation rate (Kilburn 2000).