Glossary

In plate tectonics a subduction zone is a region where one plate (the lower plate or slab) moves under another (the upper plate) and sinks into the mantle beneath it. This process results in a convergent movement of the two involved plates which is known to generate earthquake ruptures of different types. These ruptures are classified according to the part of the subduction zone where they occur. Interface ruptures are those that occur at the contact between the two plates; intraslab ruptures are those that occur within the slab; outer-rise ruptures also occur within the slab but in the region in front of the trench or the tip of the accretionary wedge; and splay ruptures which are those that propagate from the slab interface into the upper plate.

A fault that is capable of generating earthquakes. 

The average time span between two comparably large earthquakes on a particular seismogenic fault.

An event or process possibly detected by geological/geophysical tools and analyses that occurs between two significant earthquakes.

The recent and ongoing record of earthquakes that have occurred since the availability of modern-era seismometers (i.e. since the XXth century).

The historical record of ca. pre-XXth century earthquakes that have been parameterized in specific historical catalogues.

The brittle result of a fault that ruptures the ground surface.

A fault is a fracture along which the blocks of the Earth's crust on either side have moved relative to one another parallel to the fracture.

The angle by which a fault is more or less steep from the top towards the bottom.

The depth range that includes the location of the causative (i.e. seismogenic) fault of an earthquake – either a particular one or an expected/forecasted one – within the crust (or below depending on cases).

An event or process detected by geological/geophysical tools and analyses that is directly associated with earthquake activity.

An event or process detected by geological/geophysical tools and analyses that is apparently not accompanied by earthquake activity.

An active fault is a fault that has slipped during the present seismotectonic regime and is therefore likely to have renewed displacement in the future.