Respuesta :
Magma composition plays a major part in determining the form of a volcano.
Answer:
Magma composition
Explanation:
A volcano is any opening of the earth's surface through which the materials of the inner structure of the planet leave in the form of lava, ash and hot gases. There are several types of volcanoes, and therefore, they come in many shapes and sizes, from simple grooves to colossal mountains with prominent peaks. According to the European Space Agency, there are currently about 1,500 active volcanoes on Earth.
A volcano is formed as a result of the internal movements of the planet. As you know, the Earth is never still, and the tectonic plates, which are portions of the earth's crust, move continuously because the differences in temperature and pressure in the upper mantle generate convection currents that in turn move the materials and eventually they favor the movement of the plates.
Magma is produced by the fusion of rocks in the upper mantle and the lower part of the crust, especially in the limits of convergent and divergent plates. It is a mixture of molten or semi-molten rocks, but it can also contain gas bubbles, dissolved gases and suspended crystals.
Since magma is less dense than the rocks around it because it is hotter, it rises through the cracks or fractures of the crust and in its wake it carries other materials along. At some point it accumulates in cavities that are called magmatic chambers. When large amounts of magma accumulate and are pushed from below, they can rise and break the crust, after which magma comes out with all its contents. The expelled magma is lava.
Over the course of several years, volcanoes are modified. At first they can be low, but after numerous eruptions they reach considerable heights and develop their classic conical shape. Others stay low, erupt sometimes and stop. In highly developed volcanoes, it is possible for lava to exit through the main crater or through new cracks. On the other hand, sometimes only gases or ashes and no fluid material come out.
Much of the form acquired by the volcano is due to the characteristics of magma.