Volcanoes. They provide a variety of hints to warn us that they are preparing themselves to erupt. They can hint at when we should take the necessary evacuation procedures to head for safer grounds away from the threatening volcano. Volcanoes provide clues as to if they are going to erupt and when we should evacuate the area when they finally decide that they are.
Clue number one is seismic activity, or earthquakes, around the volcanic location. Earthquakes are created in short and long lasting time frames as the volcano prepares itself for its big boom. Clue number two is that the volcano will emit gases that have been stored deep inside the Earth as the magma steadily approaches the surface world outside of the crust.
Clue number three is ground deformation. Magma begins to accumulate near the surface causing the volcano to swell and bulge noticeably. Clue number four is thrust faults near the crater of the volcano due to the pushing magma beneath the surface of the Earth. The upper layers of rock is pushed and shoved up and over the lower layers of rock by the magma underneath as it forces its way to the surface.
Evacuation times and procedures are different for every volcano. The time of evacuation depends entirely on the size of the area, the population, mobility of the population, transport facilities available, and the general technological development of the area. Evacuation could need to be immediate or could be gradual and spread out over twenty-four hours, it all depends on the volcano and where it is in the world. So evacuation away from the volcanically active area all is dependant on what it is like around it. Plus, the more that is known about specific volcanoes, the more important the clues are to the time of evacuation, but it is still different for every volcano.
Volcanoes can be deadly of their warnings are ignored and proper evacuation procedures not followed out. Watch as volcanoes steadily change as they give us all of their warnings. Though the evacuation times are different, there is one thing that they all have in common: the need to get away from the danger that has been presented.