Scientists monitor volcanoes using a range of techniques, including seismographic detection of earthquakes and tremors that nearly invariably precede eruptions, accurate measures of ground deformation that typically follow magma rise, changes in volcanic gas emissions, and changes in gravity and...
Volcanologists study volcanoes by analyzing past events and building mathematical models of their activity. They then use information from the present day to try and predict future behavior.
Volcanology is also used to understand how volcanoes work. We know quite a bit about the structures of volcanoes from studies of preserved specimens, but it is difficult to examine live volcanoes due to the danger involved with near-surface geology. So we rely on simulations using data gathered from other volcanoes and measurements taken during actual eruptions.
In addition, new technologies have made it possible to measure things such as thermal radiation and magnetic fields around active volcanoes, which provides further information about their interior structure.
Finally, scientists can study past eruptions by looking at rocks removed from beneath active volcanoes or remnants left by extinct ones.
The study of volcanoes has helped us understand how the earth's surface has changed over time, led to the discovery of many new species, and even saved lives when warning signs of an approaching eruption were observed.
How to Investigate a Volcano
Seismologists investigate earthquakes and their aftereffects, such as tsunamis and landslides. They may also keep an eye out for earthquakes and other signals of an impending eruption at active volcanoes. In fact, one of the first signs that a volcanic eruption is approaching is usually seen by seismic scientists: a rise in the number of small earthquakes surrounding the volcano.
They are often called "earthquake hunters" because they spend much of their time in places where there are no human inhabitants; instead, they watch over large areas of land for signs of danger. When an earthquake occurs, the seismologist can quickly determine its origin and direction using the information obtained from various sensors placed throughout the area. This allows the scientist to then visit the site of the earthquake in order to collect data about it.
In addition to monitoring natural disasters, many seismologists work on projects designed to prevent future tragedies. For example, some seismologists have studied the damage caused by past earthquakes and used this knowledge to design better building codes that can protect people from being killed when dangerous conditions arise during construction or renovation projects. Others focus on detecting signals of danger before they cause harm by alerting officials to possible terrorist attacks or nuclear accidents before they occur.
Finally, some seismologists study how earthquakes change the landscape below them.
Volcanoes are being monitored. Seismometers are used to detect earthquakes that occur near an eruption. Tiltmeters and GPS satellites are used to monitor any changes in the terrain. They use robots named "Spiders" to monitor gases escaping from a volcano. Near an eruption, there is often an increase in the emission of sulphur dioxide. This occurs because the hot lava flows break down rock, releasing gas bubbles within the flow. These gas bubbles make their way to the surface where they are released into the atmosphere.
Scientists can also estimate how much lava is flowing from a volcano by measuring the height of its eruptions (using seismometers) and determining the change in its environment (using sensors on airplanes or orbiting satellites). Finally, they may simply wait and see if it blows its top!
All these methods have their limitations, but together they provide scientists with many opportunities to watch volcanos erupt.