What characteristics of magma will form a shield volcano?
Shield volcanoes are composed almost entirely of relatively thin lava flows built up over a central vent. Most shields were formed by low viscosity basaltic magma that flows easily down slope away from the summit vent.
What is a shield volcano magma?
Shield volcanoes are formed by lava flows of low viscosity – lava that flows easily. Consequently, a volcanic mountain having a broad profile is built up over time by flow after flow of relatively fluid basaltic lava issuing from vents or fissures on the surface of the volcano.
What type of magma erupts from shield volcanoes?
Shield volcanoes They are built up slowly by the accretion of thousands of highly fluid lava flows called basalt lava that spread widely over great distances, and then cool as thin, gently dipping sheets. Lavas also commonly erupt from vents along fractures (rift zones) that develop on the flanks of the cone.
What are the characteristic of shield volcano?
Shield volcanoes have the following characteristics: basic lava, which is non-acidic and very runny. gentle sides as the lava flows for long distances before it solidifies. no layers, as the volcano just consists of lava.
What is the main hazard associated with a shield volcano?
Hazard aspects of shield volcanoes include lava flows, near-source ballistics and pyroclasts, phreatomagmatic explosions, and degassing.
What are the characteristics of a shield volcano?
Shield Volcano Characteristics. The characteristics of a shield volcano are as follows: Shield Volcanoes are composed of basaltic magma (high in temperature, very low on silica and gas content.) The lava erupted from the shield volcanoes are runny and non-acidic. As the erupted lava is runny, they flow long distances before they solidify.
How are the characteristics of a volcano determined?
Since volcanic eruptions are caused by magma(a mixture of liquid rock, crystals, and dissolved gas) expelled onto the Earth’s surface, we must first discuss the characteristics of magma and how magmas form in the Earth. Characteristics of Magma Types of Magma Types of magma are determined by chemical composition of the magma.
What are the characteristics of a non explosive magma eruption?
Non explosive eruptions are favored by low gas content and low viscosity magmas (basaltic to andesitic magmas). If the viscosity is low, non-explosive eruptions usually begin with fire fountains due to release of dissolved gases.
How did a shield volcano get its name?
A shield Volcano is one of the three types of volcanoes (the other two being Cinder Cone Volcanoes and Composite Volcanoes). It gets its name from its upper view, in which it looks like a war shield.