The Alhama failure has caused most of the earthquakes in the southeast of the Iberian Peninsula.

The word “earthquake” derives from the Latin “terra” (earth) and “motus” (movement), “earthquake” comes from a Greek word meaning “jerk”. The night of the 9th to January 10th 2013, the residents of the geographical area between the provinces of Granada and Jaen (Spain) felt the effects of an earthquake of 3.8 degrees on the Richter scale, which fortunately did not result in personal injury or materials.

What is an earthquake?

From a very basic point of view, the Earth is divided into three parts: core, mantle and crust (which is where we live). The bark and the outer part Mantle Lithosphere form is really the surface of our planet, this layer “floats”, literally, on the rest of the mantle and is divided into pieces called tectonic plates that move, either to join or separated, and are responsible for the faults, volcanoes and earthquakes.


The faults

The crust has cracks that may be associated, at times, to the borders of tectonic plates, are called faults. One of the most active in Europe is located along 80 km (with a depth of 200 km) between Sewer (Murcia) and the town of Huercal-Overa (Almería) is called Alhama fault and recent studies has suffered in the last 300,000 years, six earthquakes with a magnitude greater than seven degrees on the Richter scale that can be considered “great earthquakes”. The immediate consequence of this analysis is that it was not considered, correctly, the danger of the area and that we must take into account this data to conveniently schedule when construction formats and evacuation plans since, according to that study can be repeated.


Aftershocks are earthquakes, following the earthquake, which generally tends to have smaller magnitude. In the vicinity of the area where an earthquake has occurred, there are large rock masses tend to relocate and stabilize, in this process can result in large displacements of land held that seat again. In Oaxaca (Japan), in September 1978, an earthquake with a magnitude of 6.8 degrees between September and February the following year, produced more than 200 aftershocks in the area daily.