Describe in general how the history of the volcano, as determined in this particular valley, has changed through time as reveale
d by the deposits found with depth in the drill hole. In particular note how the SiO2 content of the magmas has changed with time and whether or not this is reflected in the explosivity of the eruptions as revealed by the deposits
As the magma from the volcano rises up it begins to settle as crystals and causes the chemical compositions to change and the magma has less of magnesium and more of the silica contents.
A volcano that has more of silica oxide and a high temperature but low silica contents results in a more fluid or basaltic magma and a high content result in a viscous magma and they are of high explosive in nature like the Stromboli volcano and Mount Vesuvius.
Predicting earthquakes is a very complex task as compared to that of the volcanic eruptions that take place as a consequence of these quakes. Not even the USGS can accurately predict these earthquakes as an earthquake occurs from deep within the layers of the earth and thus it is quite difficult to predict how shallow these depths are.
<u>Monitoring and predicting the behavior</u> of an active or extinct or dominant type of volcano is much easier as they can be studied based on magma and lava, for example, the swelling inside a volcano can predict that magma has accumulated near the surface.
Movement of magma and gases through the hydrothermal vents can be done through the thermal monitoring system also a volcano can bee seen on the surface and a earthquake in the seismic wave form underneath the surface is not.
The Earth has a tilt of 23.5 degrees on its axis. This tilt causes the seasons because certain parts of the Earth are naturally tilted towards the Sun more depending on the Earth's location in its revolution around the Sun. The Tropics of Cancer and Capricorn are located at 23.5º North and South of the equator respectively, and this number comes from the tilt.
