Morocco struggles after rare, powerful earthquake kills and injures scores of people

Morocco struggles after rare, powerful earthquake kills and injures scores of people

Subject :Geography

Section Physical geography

Context:

• A powerful earthquake of magnitude 6.8 hit the Marrakech and surrounding region in Morocco. The biggest earthquake in a North African country in 120 years.

Details:

• Most affected province and city: Al Haouz province and Taroudant, Agadir, Al Hoceima (Mediterranean port city)

• Doctors Without Borders, or MSF offers help.
  • Médecins Sans Frontières, also known as Doctors Without Borders, is a charity that provides humanitarian medical care. It is a non-governmental organization (NGO) of French origin known for its projects in conflict zones and in countries affected by endemic diseases.

Morocco bordering countries:

• Morocco has a coast by the Atlantic Ocean that reaches past the Strait of Gibraltar into the Mediterranean Sea. It is bordered by Spain to the north (a water border through the Strait and land borders with three small Spanish-controlled exclaves, Ceuta, Melilla, and Peñón de Vélez de la Gomera), Algeria to the east, and Western Sahara to the south. Since Morocco controls most of Western Sahara, its de facto southern boundary is with Mauritania.

Abraham Accord: The U.S.-brokered accords that formalized ties between Israel and some Arab nations.

Shallow and dangerous earthquake:

• As per the US Geological Survey, the earthquake had a magnitude of 6.8. An aftershock of magnitude 4.9 earthquake rocked the region just 19 minutes later.
• Epicenter of the quake: The town of Ighil, roughly 70 km south west of Marrakech.
• Depth of the epicenter: 18.5 km (shallow earthquake).
  • Such quakes are generally more dangerous as they carry more energy than when they emerge to the surface, when compared to quakes that occur deeper underneath the surface.
  • While deeper quakes do indeed spread farther as seismic waves move radially upwards to the surface, they lose energy while traveling greater distances.
• Cause of the earthquake:
  • Such quakes occur due to the “northward convergence of the African plate with respect to the Eurasian plate along a complex plate boundary.”
  • With respect to this quake, the USGS attributed it to “oblique-reverse faulting at shallow depth within the Moroccan High Atlas Mountain range”.
  • The Atlas Mountains span about 2,300 kilometers across Morocco, Algeria and Tunisia. Known as fold mountains, they were created by the collision of tectonic masses: the Eurasian Plate to the north and the African Plate to the south.
• Why did it cause so much damage?
  • Earthquakes are not common in North Africa, so there was very little preparation.
  • Buildings are compact and do not follow earthquake norms.
• Faults:
  • A fault is a fracture or zone of fractures between two blocks of rock. Faults allow the blocks to move relative to each other, causing earthquakes if the movement occurs rapidly. During a quake, the rock on one side of the fault suddenly slips with respect to the other.’
  • Faults which move along the direction of the dip plane are dip-slip faults, whereas faults which move horizontally are known as strike-slip faults.
  • Oblique-slip faults show characteristics of both dip-slip and strike-slip faults. The term ‘reverse’ refers to a situation where the upper block, above the fault plane, moves up and over the lower block. This type of faulting is common in areas of compression — when one tectonic plate is converging into another.