The Bahía Solano Fault (Spanish: Falla Bahía Solano), Utría Fault or Utría-Bahía Solano Fault is a westward dipping thrust fault in the department of Chocó on the Pacific Coast of Colombia. The fault has a total length of 290.6 kilometres (180.6 mi) and runs along an average north–south strike of 347 ± 13 from the Panama-Colombia border to Bajo Baudó. The fault is partly offshore in the bays of Solano and Utría and crosses the Chocó Basin and the coastal Serranía del Baudó. Movement of the fault produced the Mw  6.5 1970 Bahía Solano earthquake.

Bahía Solano Fault
Falla Bahía Solano, Utría Fault, Utría-Bahía Solano Fault
ShakeMap of the 1970 Bahía Solano earthquake
Map showing the location of Bahía Solano Fault
Map showing the location of Bahía Solano Fault
EtymologyBahía Solano
Coordinates05°53′13″N 77°21′47″W / 5.88694°N 77.36306°W / 5.88694; -77.36306
Country Colombia
RegionPacific/Chocó
StateChocó
CitiesNuquí
Characteristics
RangeSerranía del Baudó
Part ofPacific thrust faults
Length290.6 km (180.6 mi)
Widthup to 5 km (3.1 mi)
Strike347 ± 13
DipWest
Dip angleunknown
Displacement0.2–1 mm (0.0079–0.0394 in)/yr
Tectonics
PlatePanama, Coiba, North Andean
StatusActive
Earthquakes1970 Bahía Solano (Mw  6.5)
TypeThrust fault
MovementReverse
Rock unitsUva Formation, Baudó Basalt
AgeQuaternary
OrogenyAndean

Etymology

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The fault is named after Bahía Solano, Chocó.[1]

Description

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The Bahía Solano Fault extends along the Pacific Coast of Colombia, bordering the Panama, Coiba, Malpelo and North Andes Plates.[2] It bounds a structural valley between the Solano Bay and Utría Bay, and displaces the Eocene turbidites of the Uva Formation in the south,[3][4][5] and Cretaceous oceanic Baudó Basalts in the north,[6][7][8][9] The fault forms a well developed and continuous fault line (scarp),[1] and the brecciated zone of the fault reaches 5 kilometres (3.1 mi) in width.[10] The peninsulas of Cabo Corrientes and Bahía Solano are composed of oceanic crust displaced by the Bahía Solano Fault.[11]

Segments of the fault have been called Utría Fault,[4][5][7][9][11] and Utría-Bahía Solano Fault.[8]

Activity

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The slip rate of the fault is estimated at between 0.2 and 1 millimetre (0.0079 and 0.0394 in) per year.[1] The fault is active and produced the 1970 Bahía Solano earthquake with a moment magnitude of 6.5 and a depth of 15 km (9.3 mi).[12][13] The earthquake was followed by 123 aftershocks in the period from September 26 to October 7, 1970.[14]

See also

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References

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  1. ^ a b c Paris et al., 2000, p.16
  2. ^ Zhang et al., 2017
  3. ^ Galvis Vergara, 1980, p.10
  4. ^ a b Plancha 183, 2002
  5. ^ a b Plancha 202, 2002
  6. ^ Galvis Vergara, 1980, p.23
  7. ^ a b Plancha 127, 2002
  8. ^ a b Plancha 143, 2002
  9. ^ a b Plancha 163, 2002
  10. ^ Galvis Vergara, 1980, p.31
  11. ^ a b Galvis Vergara, 1980, p.34
  12. ^ Ramírez, 1975, p.207
  13. ^ USGS. "M 6.5 - near the west coast of Colombia". United States Geological Survey. Retrieved 2017-09-18.
  14. ^ Ramírez, 1975, p.208

Bibliography

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Maps

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Further reading

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  • Page, W.D (1986), Seismic geology and seismicity of Northwestern Colombia, San Francisco, California, Woodward-Clyde Consultants Report for ISA and Integral Ltda., Medellín, pp. 1–200