Bucaramanga-Santa Marta Fault

Bucaramanga-Santa Marta Fault
Bucaramanga-Santa Marta Fault System (Sistema de) Falla(s) de Bucaramanga-Santa Marta
View of the Bucaramanga Fault along Bucaramanga
Location of the fault in Colombia
Topographic map of northern Colombia showing the fault
Etymology	Bucaramanga, Santa Marta
Country	Colombia
Region	Caribbean, Andean
State	Magdalena, Cesar, Norte de Santander, Santander
Cities	Santa Marta, El Paso, Bucaramanga, Floridablanca, Piedecuesta
Characteristics
Elevation	1–1,500 m (3.3–4,921.3 ft)
Range	Sierra Nevada de Santa Marta Eastern Ranges  Andes
Part of	Andean faults
Segments	Santa Marta, Algarrobo, Bucaramanga Faults
Length	674 km (419 mi)
Strike	341 ± 23 (NNW-SSE)
Displacement	110 km (68 mi)
Tectonics
Plate	South American Plate
Status	Active
Earthquakes	Pre-Columbian era (~1020 AD)
Type	Strike-slip fault
Movement	Sinistral
Rock units	Gaira Schist, Bucaramanga Gneiss
Age	Neogene-Holocene
Orogeny	Andean

The Bucaramanga-Santa Marta Fault (BSMF, BSF) or Bucaramanga-Santa Marta Fault System (Spanish: (Sistema de) Falla(s) de Bucaramanga-Santa Marta) is a major oblique transpressional sinistral strike-slip fault (wrench fault) in the departments of Magdalena, Cesar, Norte de Santander and Santander in northern Colombia. The fault system is composed of two main outcropping segments, named Santa Marta and Bucaramanga Faults, and an intermediate Algarrobo Fault segment in the subsurface. The system has a total length of 674 kilometres (419 mi) and runs along an average north-northwest to south-southeast strike of 341 ± 23 from the Caribbean coast west of Santa Marta to the northern area of the Eastern Ranges of the Colombian Andes.

The fault system is a major bounding fault for various sedimentary basins and igneous and metamorphic complexes. The northern Santa Marta Fault segment separated the Sinú-San Jacinto Basin and Lower Magdalena Valley in the west from the Sierra Nevada de Santa Marta to the east. The buried Algarrobo Fault segment forms the boundary between the Lower Magdalena Valley and northern Middle Magdalena Valley to the west and the Cesar-Ranchería Basin in the east. The Bucaramanga Fault segment separates the middle part of the Middle Magdalena Valley in the west from the Santander Massif in the east.

Studies of the fault segments have shown the fault was active in the pre-Columbian era, around the year 1020, when the area around Bucaramanga was inhabited by the Guane. Various seismic events analysed to have occurred during the Holocene of the Bucaramanga Fault segment lead to the conclusion the fault is active.