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The Hawaiian Islands - Coggle Diagram

- - - - This shows that there was a change in the direction of plate movement around 43-45 million years ago
- - - - Typically have slopes of only 2-3*
  - - - 4,206m above sea level
        
        9km to the ocean floor below water
    - - 4,169m above sea level
        
        5km to the ocean floor below water
        
        Further compressed due to weight by 8km
        
        Making the volcano over 17km in height from base to summit
      - ACTIVE VOLCANO
    - - 1,219m above sea level
        
        3,700m to the ocean floor below water
      - EXPREMELY ACTIVE VOLCANO from the end of the 18th century to the present
      - Situated on the south eastern slope of Hawaii
    - - Currently forming 20 miles from the south coast of Hawaii
        
        975m below sea level
        
        Predicted to reach the surface and emerge from the Pacific Ocean in around 100,000 years
  - - - The caldera has 120m high walls and its floor is covered in solidified lava flows and a circular depression called Halema'uma'a crater
        
        exhibited lava lake from 1838-1924 and again in 2008
- - - - signs volcanoes are active but not erupting
  - - - 1983-2001
      - destroyed 13km of highway and approximately 180 buildings
        
        Almost the entire destruction of the village of Kalapana
    - - Pahoehoe
        
        roughly translates to 'flat and swirly', refers to lava flows with smooth, rope-like surfaces
      - A'a
        
        flows with jagged, rough or 'clinkery' surfaces
  - - - lava is rapidly cooled when in contact with the air, forming dark clouds of cinders
        
        cooled material can often be fine and can be carried for many miles away from the vent
        
        though impressive, the results are only mildly explosive volcanic activities
  - - - has been erupting continuously since 1986
        
        this eruption has been associated with the release of about 2,000 tonnes of sulfur dioxide, per day, into the atmosphere
        
        this gas is carried up the Kona coast by low-altitude winds, reacting with moisture in the air to form sulphuric acid droplets known as vog
        
        vog can travel 100 miles or more depending on wind patterns
  - - - this explosivity probably resulted from expanding steam, generated from heated water on or near to the ground as it mixed with magma and hot rocks
- - - - it is termed lapilli when between 0.1 and 2.5 inches
        
        material larger than 2.5 inches is called volcanic blocks if ejected in a solid state, and volcanic bombs if fired from the volcano in a semisolid state
        
        the semisolid nature of the bombs means that they can change shape as projected through the sir and landing and may be described as 'ribbon', 'bread-crust', or even 'cow-dung' bombs
        
        Scoria or cinder is irregular-shaped material the size of bombs or lapilli. It is formed from frothy lava and which may contain small holes formed as lava from which gas was trying to escape cooled very rapidly during fountaining. These holes are called vesicles and if the scoria has holes then it is termed pumice
        
        some pumice which is particularly light is called reticulite or thread-lace scoria. Given its extremely fine and light nature, it can be carried many miles from the fountains by wind.
        
        if the scoria remains in a plastic state when it hits the ground it may splat or splash and is called splatter, if a number of 'blobs' join together they are known as agglutinate or welded splatter.
        
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