Paraíso Fault

Paraíso Fault
	Falla de Paraíso, Palmira-Buga Fault
Etymology	Hacienda El Paraíso, Palmira, Buga
Coordinates	03°34′37″N 76°18′18″W
Country	Colombia
Region	Andean
State	Valle del Cauca
Cities	Buga, Palmira
Characteristics
Range	Central Ranges
Part of	Romeral Fault System
Segments	North and south
Length	35.3 km (21.9 mi)
Strike	012.5 ± 3
Dip	East to northeast
Dip angle	Variable from 12 to 30
Displacement	0.2–1 mm (0.0079–0.0394 in)/yr
Tectonics
Plate	North Andean
Status	Active
Type	Thrust fault
Movement	Reverse, minor dextral
Age	Quaternary
Orogeny	Andean

The Paraíso Fault or Palmira-Buga Fault (Spanish: Falla de Paraíso, Falla de Palmira-Buga) is a thrust fault with minor dextral lateral movement in the department of Valle del Cauca in southwestern Colombia. The fault is part of the megaregional Romeral Fault System and has a total length of 35.3 kilometres (21.9 mi) and runs along an average north-northwest to south-southeast strike of 012.5 ± 3 in the Cauca Basin and the Central Ranges of the Colombian Andes.

Etymology

The fault is named after hacienda El Paraíso.[1] An alternative name is Palmira-Buga Fault.[2]

Description

The Paraiso Fault is part of the Romeral Fault System in southwestern Colombia. It is located at the western slope of the Central Ranges, east of the city of Palmira. The fault displaces alluvial fans and debris flows on the eastern border of the Valle del Cauca Department. North of the Amaime River, the fault seems to be more active in late Quaternary than the portion south of the river.[1]

The Paraiso Fault is concave to the east and shows an outstanding linear trace for more than 20 kilometres (12 mi). The fault is divided in two portions: the southern portion, about 15 kilometres (9.3 mi) long, is located to the south of the Amaime River; the northern part extends about 7 kilometres (4.3 mi) north of the river. Geographic expression suggests that the northern portion is more active than the southern one. The fault is characterised by a series of discontinuous short sinuous scarps of about 1 to 2 kilometres (0.62 to 1.24 mi) long. The height of the scarps varies from 2 to 10 metres (6.6 to 32.8 ft).[1]

Activity

The fault is considered active with Holocene tectonic movement. Two trenches were opened in the northern part of the fault: the Venecia and Piedechinche trenches, each of which show Holocene tectonic deformation. Movement is well defined as early Holocene, it is younger than 6,320 yr as determined from C-14 ages of folded paleosoils sampled in the Venecia trench.[3]

References

Paris et al., 2000a, p.22
Mapa Geológico Valle del Cauca, 2001
Paris et al., 2000a, p.23

Bibliography

Paris, Gabriel; Michael N. Machette; Richard L. Dart, and Kathleen M. Haller. 2000a. Map and Database of Quaternary Faults and Folds in Colombia and its Offshore Regions, 1–66. USGS. Accessed 2017-09-18.

Maps

Paris, Gabriel; Michael N. Machette; Richard L. Dart, and Kathleen M. Haller. 2000b. Map of Quaternary Faults and Folds of Colombia and Its Offshore Regions, 1. USGS. Accessed 2017-09-18.
Nivia, A.; W.J. McCourt; J.A. Aspden; M. De Armas, and J.W. Aucott. 2001. Mapa Geológico del Valle del Cauca 1:250,000, 1. INGEOMINAS. Accessed 2017-09-21.