Motagua Fault
Motagua Fault Zone
LocationGuatemala and Mexico
Tectonics
PlateNorth American Plate, Caribbean Plate
StatusActive
Earthquakes1717, 1773, 1902, 1976, 1980, 2009
Typetransform fault

The Motagua Fault (also, Motagua Fault Zone) is a major, active left lateral-moving transform fault which cuts across Guatemala. It forms part of the tectonic boundary between the North American Plate and the Caribbean Plate. It is considered the onshore continuation of the Swan Islands Transform Fault and Cayman trench, which run under the Caribbean Sea.[1] Its western end appears not to continue further than its surface trace,[2] where it is covered by Cenozoic volcanics.[1]

The Motagua Fault is regarded by some geologists as part of a system of faults designated the "Motagua-Polochic system" rather than as a discrete single boundary. The Polochic fault (also referred to as the Chixoy-Polochic Fault) lies north and parallel to the Motagua Fault and shares some of the motion between the North American and Caribbean Plates.[1]

Earthquakes

Along the Motagua Fault trace (1976 Guatemala earthquake) where it crosses the Gualán soccer field. This zigzag type of fault trace is known as "mole track", which is best developed in hard-packed, brittle surface materials.

The Motagua Fault has been responsible for several major earthquakes in Guatemala's history, including the 7.5 Mw Guatemala 1976 earthquake, and is also notable for its significant visible fault trace.[3]

References

  1. ^ a b c Lyon-Caen, H.; Barrier, E.; Lasserre, C.; Fraco, A.; Arzu, I.; Chiquin, L.; Chiquin, M.; Duquesnoy, T.; Flores, O.; Galicia, O.; Luna, J.; Molina, E.; Porras, O.; Requena, J.; Robles, V.; Romero, J.; Wolf, R. (2006). "Kinematics of the North American-Caribbean-Cocos plates in Central America from new GPS measurements across the Polochic-Motagua fault system". Geophysical Research Letters. 33 (L19309). doi:10.1029/2006GL027694. S2CID 3161221.
  2. ^ Guzmán-Speziale, Marco (2010). "Beyond the Motagua and Polochic faults: Active strike-slip faulting along the Western North America-Caribbean plate boundary zone". Tectonophysics. 496 (1–4): 17–27. doi:10.1016/j.tecto.2010.10.002.
  3. ^ USGS Historic Earthquakes

15°08′N 89°22′W / 15.133°N 89.367°W / 15.133; -89.367

External links


Tectonic plates of Central America (Pacific Plate–North American Plate–Caribbean Plate Convergence Zone)
Major seismically active faults of North America
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