Over 80 per cent of large earthquakes occur around the edges of the Pacific Ocean, an area known as the ‘Ring of Fire’; this where the Pacific plate is being subducted beneath the surrounding plates. The Ring of Fire is the most seismically and volcanically active zone in the world.

plate boundaries

Earthquakes occur on faults – strike-slip earthquakes occur on strike-slip faults, normal earthquakes occur on normal faults, and thrust earthquakes occur on thrust or reverse faults. When an earthquake occurs on one of these faults, the rock on one side of the fault slips with respect to the other.

The epicenter is the point on the earth’s surface vertically above the hypocenter (or focus), point in the crust where a seismic rupture begins.

Earthquake epicentres are not randomly distributed on earth. They occur wherever two tectonic plates meet. The collision of these plates leads to the occurrence of earthquakes and volcanoes.

Pacific Ring of Fire

Volcanoes are not randomly distributed over the Earth’s surface. Most are concentrated on the edges of continents, along island chains, or beneath the sea forming long mountain ranges. Major tectonic plates of the Earth.

The distribution of earthquakes on map is based on the plate tectonics. Explanation: The earthquakes are distributed all over the globe and are found along the fault line and lines of plate subsidence.

Earthquakes can also occur within plates, although plate-boundary earthquakes are much more common. Less than 10 percent of all earthquakes occur within plate interiors. As plates continue to move and plate boundaries change over geologic time, weakened boundary regions become part of the interiors of the plates.

Is there any place in the world that doesn’t have earthquakes? Florida and North Dakota are the states with the fewest earthquakes. Antarctica has the least earthquakes of any continent, but small earthquakes can occur anywhere in the World.

Answer. It is important to identify areas that are prone to earthquakes in order to prepare for the possibility that they may occur. If there is an area that rarely receives earthquakes of any significant size, there is no reason to construct every bridge, building, etc, to be earthquake resistant.

There are seven main factors that determine the impact of an earthquake:

• Distance (along the surface and depth)
• Severity (measured by the Richter scale)
• Population density.
• Development (building quality, financial resources, healthcare, infrastructure, etc.)
• Communication links.

As populations increase, areas near volcanoes are being developed and aviation routes are increasing. As a result, more people and property are at risk from volcanic activity. Volcanic eruptions are one of Earth’s most dramatic and violent agents of change.

Answer: This non-stop movement causes stress on Earth’s crust. When the stresses get too large, it leads to cracks called faults.

crust

Earthquake. Earthquakes are caused due to the release of energy, which generates waves that travel in all directions. To understand in simple terms it is the shaking of the earth.

Answer: It’s because of the tectonic plates’ movement and volcanic activity. Explanation: The Philippines is located at various fault lines which causes the earthquakes.

There are five active fault lines in the country namely the Western Philippine Fault, the Eastern Philippine Fault, the South of Mindanao Fault, Central Philippine Fault and the Marikina/Valley Fault System.

Epicenter is the location on the surface of the Earth directly above where the earthquake starts. Focus (aka Hypocenter) is the location in the Earth where the earthquake starts.