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What is rough lava called?
ʻAʻā is basaltic lava characterized by a rough or rubbly surface composed of broken lava blocks called clinker. The Hawaiian word was introduced as a technical term in geology by Clarence Dutton. The loose, broken, and sharp, spiny surface of an ʻaʻā flow makes hiking difficult and slow.
What are two types of Hawaiian lava flows?
Pahoehoe (pronounced “pah-hoy-hoy”) and aa (pronounced “ah-ah”) are the two main types of Hawaiian lava flows, and these two Hawaiian names, introduced into the scientific literature in the late 19th century, are now used by volcanologists worldwide to describe similar lava-flow types.
What do Hawaiians call lava?
Pāhoehoe
Pāhoehoe and ʻaʻā are both Hawaiian words that are used worldwide to describe these kinds of lava. ʻAʻā translates into “stony rough lava”, but also to “burn, blaze, glow” or “fire”.
What are the 3 types of lava flow?
The most common way to divide lava flows into distinct types is following: Pahoehoe lava flow, Aa lava flow, Blocky lava flow, and also Pillow lava flow.
What is a basaltic lava flow?
Lesson Summary. Basaltic lava, or mafic lava, is molten rock enriched in iron and magnesium and depleted in silica. Basaltic magmas are formed by exceeding the melting point of the mantle either by adding heat, changing its composition, or decreasing its pressure.
What is blocky lava flow?
A surface flow of hot, molten lava covered in a carapace of crystalline, angular blocks which tend to be smoothly faceted and may have dimensions up to several metres. Blocky lava morphology is usually confined to lavas of high viscosity and intermediate to high silica contents.
What is smooth lava called?
Smooth Lava: Pahoehoe A classic lava flow with a smooth surface and curved ripples and folds is known as pahoehoe. Pahoehoe is the name of both the lava type and of the whole lava flow. Pahoehoe lava flows are formed from eruptions that are not very violent, but that slowly extrude lava.
What is a 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.
What is felsic lava flow?
Felsic lavas are not as hot, high in silica and volatiles, and have a high viscosity. They are thick and gooey and resist flowing. Their high volatile content makes them potentially highly explosive. Shield Volcanoes.
What is basaltic lava flow?
Basaltic lava, or mafic lava, is molten rock enriched in iron and magnesium and depleted in silica. When on land, basaltic lavas are commonly seen as pahoehoe or ‘a’a flows. Underwater, basaltic lavas are erupted as pillow basalts. More rare basaltic lava features include lava lakes and lava fountains.
What is ropy lava?
Definition of ropy lava : lava marked with wrinkles resembling rope : pahoehoe.
What does the word pahoehoe mean?
lava
: basaltic lava having a smooth, often billowy, shiny surface Thick, folded lava such as this is known by its Hawaiian nickname of pahoehoe.
What is a’a lava called in Hawaiian?
The smooth variety is called pahoehoe, and the rougher variety is known as a’a (pronounced ah-ah). A’a is a Hawaiian word meaning “stony with rough lava”. If you’ve ever been to the Big Island of Hawaii and gone for a hike, you’ve seen a’a lava.
What are the characteristics of A’a lava?
The inside of an a’a lava flow is thick and dense. Surrounding this thick dense core is a sharp spiny surface of cooling rock. These fragments of rock are carried on the top of the a’a lava flow and make a crunching grinding sound as the lava flows downhill.
What is the difference between aa lava and pahoehoe lava?
Pahoehoe lava flow is usually at least 10 times slower than typical aa lava flow 5. Higher effusion rate results in lava flow being shattered which is how the rubbly and clinkery aa lava surface forms. Pahoehoe and aa lava are strikingly different in appearance, but their composition may be identical or very similar.
How do volcanic eruptions happen in Hawaii?
A series of earthquakes trigger eruptions, where fissures allow magma to reach the earth’s surface. One of the unique features of Hawaiian lava flows is that they are considered relatively quiet, because the lava is, respective to other regions, quite fluid, and the gases escape readily.