Morocco Earthquake: M 6.8 - 56 km W of Oukaïmedene, Morocco

Date & time: 2023-09-08 22:11:01 (UTC)
Local time at epicenter: Friday, Sep 8, 2023 at 9:10 pm
Latitude/ Longitude: 31.110°N 8.440°W
Epicenter: Chichaoua, Morocco
Magnitude: 6.8
Depth: 18.5 km


Tectonic Summary

The September 8, 2023, M 6.8 earthquake near Oukaïmedene, Morocco, occurred due to oblique-reverse faulting at shallow depth within the Moroccan High Atlas Mountain range, roughly 75 km southeast of Marrakech. Focal mechanism solutions for the event indicate rupture occurred on a steeply dipping oblique-reverse fault striking to the northwest or a shallow dipping oblique-reverse fault striking to the east. The High Atlas Mountains contain a variety of mapped strike-slip and thrust faults, trending to the east-west and northeast-southwest. This earthquake occurred within the Africa Plate, approximately 550 km south of the plate boundary between the Africa and Eurasia plates. At the location of this earthquake, the African plate moves approximately 24 mm/year WSW relative to the Eurasia plate.  

While commonly plotted as points on maps, earthquakes of this size are more appropriately described as slip over a larger fault area. Reverse faulting events of the size of the September 8, 2023, Morocco earthquake are typically about 30 by 20 km (length x width).

Earthquakes of this size in the region are uncommon but not unexpected. Since 1900, there have been no earthquakes M6 and larger within 500 km of this earthquake, and only 9 M5 and larger earthquakes. Most of these events have occurred east of the September 8, 2023, earthquake.

Waveform
Listen to the waveform as audio:

ShakeMap

Nearby towns/cities
  • 56.2 km (34.9 mi) W of Oukaïmedene, Marrakesh-Safi, Morocco
  • 71.8 km (44.6 mi) SW of Marrakesh, Marrakesh-Safi, Morocco
  • 73.7 km (45.8 mi) W of Setti Fatma, Marrakesh-Safi, Morocco
  • 82.4 km (51.2 mi) NNE of Taroudant, Souss-Massa, Morocco
  • 108.2 km (67.3 mi) NE of Oulad Teïma, Souss-Massa, Morocco

MMI (Modified Mercalli Intensity) Scale:
  • VII Adassil
  • VII Azgour
  • VII Amizmiz
  • VII Tizguine
  • VI Chichaoua
  • VI Marrakesh
  • IV Safi
  • IV Agadir
  • IV Casablanca
  • IV Beni Mellal
  • IV Guelmim

Sources:
  • USGS: M 6.8 - 56 km W of Oukaïmedene, Morocco
  • IRIS 

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