Septentrional-Oriente fault zone

The Gonâve Microplate, showing location of the main fault zones

The Septentrional-Orient fault zone (SOFZ) is a system of coaxial left lateral-moving strike slip faults which runs along the northern side of the island of Hispaniola where the Dominican Republic and Haiti are located. The SOFZ shares approximately half of the relative motion between the North American and Caribbean tectonic plates with the Enriquillo-Plantain Garden fault zone which runs along the southern side of Hispaniola. Both faults merge into the Cayman Trench to the west. Some researchers believe that the Enriquillo-Plantain Garden fault zone and the SOFZ bound a microplate, dubbed the Gonâve Microplate, a 190,000 km² (73,000 sq mi) area of the northern Caribbean Plate that is in the process of shearing off the Caribbean Plate and accreting to the North America Plate.

A major tremor on this fault destroyed the city of Cap-Haïtien and other cities in the northern part of Haiti and the Dominican Republic on 7 May 1842.