What type of magma makes aa?

What type of magma makes aa?

Aa forms when lava flows rapidly. Under these circumstances, there is rapid heat loss and a resulting increase in viscosity. When the solid surface crust is torn by differential flow, the underlying lava is unable to move sufficiently rapidly to heal the tear.

What is aa in Volcano?

‘A’ā (pronounced “ah-ah”) is a Hawaiian term for lava flows that have a rough rubbly surface composed of broken lava blocks called clinkers. The incredibly spiny surface of a solidified ‘A’ā flow makes walking very difficult and slow.

Which type of lava creates aa and pahoehoe?

Basaltic lava
Basaltic lava generally takes two distinct forms known by the Hawaiian terms pahoehoe and aa. Pahoehoe has a smooth wavy surface that resembles twisted rope. It advances by extruding molten toes of lava beneath a thin, flexible crust. As it travels pahoehoe lava often changes to blocky flows called aa.

What type of volcano produces pahoehoe?

Pahoehoe is a smooth, ropy lava, common on the Hawaiian islands. ‘A’a is a more chunky and thick flow, that is most commonly associated with composite volcano eruptions. ‘A’a lava flows are also called clinkers, because of their rough and jagged appearance.

What kind of lava is aa lava?

Pahoehoe is lava that in solidified form is characterized by a smooth, billowy, or ropy surface, while aa is lava that has a rough, jagged, spiny, and generally clinkery surface. In thick aa flows, the rubbly surface of loose clinkers and blocks hides a massive, relatively dense interior.

What type of lava is aa?

pahoehoe
Aa lava is a rough rubbly crust of a lava flow. It is a major lava flow type. Other important subaerial lava flow types are pahoehoe and blocky lava. Aa and pahoehoe are terms that were brought to geological terminology from the Hawaiian language.

What type of lava is aa lava?

Mafic (ferromagnesian, dark-coloured) lavas such as basalt characteristically form flows known by the Hawaiian names pahoehoe and aa (or a’a). Pahoehoe lava flows are characterized by smooth, gently undulating, or broadly hummocky surfaces.

What volcanoes have pahoehoe lava?

Pahoehoe lava flows. Kilauea volcano, Pu’u O’o vent. Forming basaltic pahoehoe lava flow in Hawaii. Such lava flows move slowly and are not overly dangerous when compared with some other volcanic phenomena.

What volcano has blocky lava?

Kilauea volcano
Lava flowing toward the sea from Kilauea volcano, Hawaii, takes two recognizable forms: fast-flowing, ropy lava, called pahoehoe, and thick, blocky lava, called aa.

What does pahoehoe lava look like?

Pahoehoe lava flows are characterized by smooth, gently undulating, or broadly hummocky surfaces. The liquid lava flowing beneath a thin, still-plastic crust drags and wrinkles it into tapestry-like folds and rolls resembling twisted rope.

What is quiet eruption?

Quiet Eruptions Volcanoes that have very hot, low-silica magma generally erupt quietly. In a quiet eruption, lava erupts in a stream of low-viscosity lava, called a lava flow. Lava flows from a quiet eruption can travel for great distances.