Pillow Lavas

Pillow Lavas and Volcanoes

Definition:Pillow lavas are lavas that contain characteristic pillow-shaped structures that are attributed to the extrusion of the lava under water that is solidified instantly by cooling with the ocean temperature.

Volcanoes made in Barrika-Meñakoz are made by the collide of the african tectonic plate and the Iberian tectonic plate.

Information:

Pillow Lavas,are characterized for being pillow-shaped.This type of rocks appear in submarine

volcanoes,that extruse lava underwater and solidifies instantly creating that pillow-shaped rock.

Volcanoes

What is an Volcano?

Volcanoes are mountains shaped  geological structures that extruse Earth´s magma or

lava and gases.

How do they appear?

Volcanoes are made in the boundaries of the tecnonic plates.

When plates collide one of them goes down  and melts creating magma.

The other one,goes up creating a mountain from when magma erupts,this mountain is

called volcano.

Products of a Volcano:

There are three types of products,Lava,Rock Fragments and Gas.

1.Lava: Lava is the name for magma that has been released onto the Earth’s surface. 

2.Rock Fragments:Volcanic dust consists of particles less than one one-hundredth inch in diameter and there is another type,Volcanic Bombs.Volcanic bombs are large fragments. Most of them range from the size of a baseball to the size of a basketball. 

3.Gas:The gases released in volcanoes are made up particularly of steam, but may also include carbon dioxide, nitrogen, sulfur dioxide, and other gases.

Types of Volcanoes

Strombolian and Hawaiian eruptions These are the least violent types of explosive eruptions. Hawaiian eruptions have fire fountains and lava flows, whereas Strombolian eruptions have explosions causing a shower of lava fragments.For Example:Etna and  Kilauea

Vulcanian eruptions :

Vulcanian eruptions are small to moderate explosive eruptions, lasting seconds to minutes.For example:Colima.

Subplinian and Plinian eruptions  

Eruptions with a high rate of magma discharge, sustained for minutes to hours. They form a

tall, convective eruption column of a mixture of gas and rock particles, and can cause wide dispersion of ash.For example:Vesubio

Icelandic Eruptions: Icelandic type is characterized by effusions of molten basaltic lava that flow from long, parallel fissures.For example:Eyjafjallajökull.

Pelean eruption: Pelean is the most destructive type of eruption