Igneous Rock Formation

• When magma emerges as lava onto the surface, it starts to cool quickly. Returning to its solid state, lava turns into igneous rocks with crystal formations -- and can also look like clear glass, with very few crystals, depending on the rate of cooling. Sometimes magma cools underground but later comes to the surface through erosion, taking the form of granite. The vast walls of granite at Yosemite National Park are an example of this.
  
  

Destruction of Existing Plant Life

• Because of the liquid heat associated with lava, any plant life under it goes by the wayside as a fatality. The liquid covering seals off the surface beneath it from oxygen, choking the life out as it solidifies into an igneous coat.
  
  

Rocky Explosions

• Occasionally, when lava comes onto the surface, it expels the gases inside it vigorously. This can lead to explosions that shoot rock, dust, lava and ashes up and out into the air. Even shattered pumice and blast up into the air and then settle down onto the land beneath.
  
  

Lava into the Sea

• Because lava that flows onto the sea's surface or along the land and into the sea hits a cooler surface, the process of cooling down goes even faster. This means that the lava actually explodes into sand and debris. One example of this would be Hawaii's beaches of "black sand" that appeared when fresh lava entered sea water.