Natural disaster

a.What is a natural disaster?

A natural disaster is an event with a natural, as opposed to human, cause that results in large-scale loss of life or damage to property. It could be related to weather, geology, biology or even factors outside the Earth. Examples are earthquakes, hurricanes, droughts and flooding.

b. Explain the causes of an earthquake or a volcanic eruption.

There are two main causes of earthquakes.

Firstly, they can be linked to explosive volcanic eruptions; they are in fact very common in areas of volcanic activity where they either proceed or accompany eruptions.

Secondly, they can be triggered by Tectonic activity associated with plate margins and faults. The majority of earthquakes world wide are of this type.

c. What is the Servicio Sismológico Nacional (National Seismic Service)? And the USGS? What is their purpose?

the National Seismological Service (SSN) is an organization that provides relevant information about the occurrence of earthquakes in the country and determines its main parameters such as the magnitude and epicenter.

The USGS is a science organization that provides impartial information on the health of our ecosystems and environment, the natural hazards that threaten us, the natural resources we rely on, the impacts of climate and land-use change, and the core science systems that help us provide timely, relevant, and useable information.

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