The Motagua Fault 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. Its western end appears not to continue further than its surface trace, where it is covered by Cenozoic volcanics.
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 Caribbean Plate is a mostly oceanic tectonic plate underlying Central America and the Caribbean Sea off the northern coast of South America.
Bathymetry of the northeast corner of the Caribbean Plate showing the major faults and plate boundaries; view looking south-west. The main bathymetric features of this area include: the Lesser Antilles Volcanic Arc; the old inactive volcanic arc of the Greater Antilles (Virgin Islands, Puerto Rico, and Hispaniola); the Muertos Trough; and the Puerto Rico Trench formed at the plate boundary zone between the Caribbean and obliquely subducting North American Plates. Vertical exaggeration is 5:1.