List of fracture zones

Major fractures zones of the Atlantic can be seen on this ocean depth map

Fracture zones are common features in the geology of oceanic basins. Globally most fault zones are located on divergent plate boundaries on oceanic crust. This means that they are located around mid-ocean ridges and trend perpendicular to them. The term fracture zone is used almost exclusively for features on oceanic crust; similar structures on continental crust are instead termed transform or strike slip faults, a denomination active fracture zones also can have. Some fracture zones have been created by mid-ocean ridge segments that have been subducted and may not longer exist.

Pacific Ocean

Major Pacific trenches (1-10) and fracture zones (11-20): 1. Kermadec 2. Tonga 3. Bougainville 4. Mariana 5. Izu-Ogasawara 6. Japan 7. Kuril–Kamchatka 8. Aleutian 9. Middle America 10. Peru-Chile 11. Mendocino 12. Murray 13. Molokai 14. Clarion 15. Clipperton 16. Challenger 17. Eltanin 18. Udintsev 19. East Pacific Rise (S-shaped) 20. Nazca Ridge

Most fracture zones in the Pacific Ocean originate from large mid-ocean ridges (also called "rises") such as the East Pacific Rise, Chile Rise and Juan de Fuca Ridge. The plates that host the fractures are Nazca, Pacific, Antarctic, Juan de Fuca and Cocos among others. Fracture zones being subducted under Southern and Central America are generally southwest-northeast oriented reflecting the relative motion of Cocos, Nazca and the Antarctic Plates.

Chile Rise

The fracture zones of the Chile Rise trend in a west to east fashion with the most southern ones taking a slightly more southwest to northeast orientation. This non-perpendicular relation to Chile’s coast reflects the oblique subduction of Nazca Plate under southern Chile. West of Chile rise the fracture zones are hosted in the Antarctic Plate. Some fracture zones such as Chile and Valdivia make up large sections of the Nazca-Antarctic Plate boundary.

Map of the Chile Rise and its fractures zones in Nazca and the Antarctic Plates
Name Minimum length
in km 		Length of transform
boundary in km		 Position at Ridge
Chile 2,250 (1,400) 1,100 (680) 35°32′23.78″S 104°37′3.32″W / 35.5399389°S 104.6175889°W / -35.5399389; -104.6175889
Chiloé 1,750 (1,090) 50 (30) 42°59′42.71″S 83°11′5.08″W / 42.9951972°S 83.1847444°W / -42.9951972; -83.1847444
Darwin 50 (30) 45°54′28.81″S 76°25′30.96″W / 45.9080028°S 76.4252667°W / -45.9080028; -76.4252667
Desolación 0
Esmeralda 0 49°06′46.50″S 80°12′32.78″W / 49.1129167°S 80.2091056°W / -49.1129167; -80.2091056
Guafo 1,550 (960) 280 (170) 44°47′55.49″S 80°15′53.07″W / 44.7987472°S 80.2647417°W / -44.7987472; -80.2647417
Guamblin 1,300 (810) 70 (40) 45°44′7.07″S 77°27′31.51″W / 45.7352972°S 77.4587528°W / -45.7352972; -77.4587528
Madre de Dios 0
Mocha 450 (280) 0 39°14′23.82″S 77°22′58.93″W / 39.2399500°S 77.3830361°W / -39.2399500; -77.3830361
Taitao 0
Tres Montes 0
Valdivia 2,100 (1,300) 650 (400) 41°23′25.45″S 87°23′35.62″W / 41.3904028°S 87.3932278°W / -41.3904028; -87.3932278

East Pacific Rise

Name Minimum length
in km 		Length as plate
boundary in km		 Coordinates
Easter
Mendaña 0
Nazca 0 19°49′28.10″S 77°35′52.91″W / 19.8244722°S 77.5980306°W / -19.8244722; -77.5980306
Quiros 0

Galapagos Rise

Juan de Fuca and Gorda Ridges

Molokai and Murray fracture zones shown in the list were created by ridge segments that no longer exist.

A map of the Juan de Fuca Plate

Atlantic Ocean

In the Atlantic Ocean most fracture zones originate from the Mid-Atlantic Ridge, which runs from north to south, and are therefore west to east oriented in general. There are about 300 fracture zones, with an average north-south separation of 55 kilometres (34 mi):[1] two for each degree of latitude. Physically it makes sense to group Atlantic fracture zones into three categories:[2]

  1. Small offset: length of transform fault less than 30 kilometres (19 mi)
  2. Medium offset: offset over 30 kilometers
  3. Large offset: offset several hundreds of kilometers

Mid-Atlantic Ridge (Northern Hemisphere)

Name Minimum length
in km 		Length of
transform fault in km		Position at Ridge
Saint Paul[3] 1451454 0°39′40″N 27°55′52″W / 0.661°N 27.931°W / 0.661; -27.931
Saint Peter[3] 33340 2°31′55″N 31°00′29″W / 2.532°N 31.008°W / 2.532; -31.008
Strakhov[3] (formerly:Four North[4]) 1814100 3°55′59″N 32°06′58″W / 3.933°N 32.116°W / 3.933; -32.116
Sierra Leone[3] 111152 6°13′48″N 33°35′17″W / 6.230°N 33.588°W / 6.230; -33.588
Bogdanov[3] 17384 7°08′06″N 34°21′04″W / 7.135°N 34.351°W / 7.135; -34.351
Vernadsky[3] 194107 7°41′35″N 37°28′59″W / 7.693°N 37.483°W / 7.693; -37.483
Doldrums[3] 381144 8°07′08″N 38°45′00″W / 8.119°N 38.750°W / 8.119; -38.750
Arkhangelskiy[3] 69199 8°51′18″N 39°56′17″W / 8.855°N 39.938°W / 8.855; -39.938
Vema[3] 822300 10°43′34″N 42°19′59″W / 10.726°N 42.333°W / 10.726; -42.333
Mercurius[5] 39 12°07′55″N 43°55′26″W / 12.132°N 43.924°W / 12.132; -43.924
Marathon[5] 78 12°36′40″N 44°25′48″W / 12.611°N 44.430°W / 12.611; -44.430
Fifteen Twenty, also known
as Barracuda or Cabo Verde[3] 		1195195[5] 15°19′12″N 45°52′16″W / 15.320°N 45.871°W / 15.320; -45.871
Vidal[2] 50 17°49′55″N 46°35′20″W / 17.832°N 46.589°W / 17.832; -46.589
Luymes South[2] 30 18°32′28″N 46°27′54″W / 18.541°N 46.465°W / 18.541; -46.465
Luymes North[2] 24 18°58′01″N 46°07′41″W / 18.967°N 46.128°W / 18.967; -46.128
Snellius[2] 41 20°36′58″N 45°45′22″W / 20.616°N 45.756°W / 20.616; -45.756
Kane[3] 1040150[6] 23°43′05″N 45°34′59″W / 23.718°N 45.583°W / 23.718; -45.583
Northern[2] 1040925°41′20″N 45°11′35″W / 25.689°N 45.193°W / 25.689; -45.193
Tyro[2] 1529°21′54″N 43°00′25″W / 29.365°N 43.007°W / 29.365; -43.007
Atlantis[3] 84366 30°04′05″N 42°22′19″W / 30.068°N 42.372°W / 30.068; -42.372
Cruiser[2] 9 32°19′23″N 40°11′42″W / 32.323°N 40.195°W / 32.323; -40.195
Charis[2] 1333°03′32″N 39°37′41″W / 33.059°N 39.628°W / 33.059; -39.628
Hayes[3] 624151 33°36′54″N 38°26′20″W / 33.615°N 38.439°W / 33.615; -38.439
Oceanographer[3] 751148 35°08′56″N 35°33′43″W / 35.149°N 35.562°W / 35.149; -35.562
Tydeman 2136°38′28″N 33°27′50″W / 36.641°N 33.464°W / 36.641; -33.464
Pico (to the west)[2][3]71967 37°28′05″N 31°53′56″W / 37.468°N 31.899°W / 37.468; -31.899
East Azores (to the east)[2][3]75867 37°28′05″N 31°53′56″W / 37.468°N 31.899°W / 37.468; -31.899
Kurchatov[3] 17420 40°32′13″N 29°27′22″W / 40.537°N 29.456°W / 40.537; -29.456
Petrov[3] 749 40°32′13″N 29°27′22″W / 40.537°N 29.456°W / 40.537; -29.456
Maxwell[3] 21 47°38′10″N 27°31′37″W / 47.636°N 27.527°W / 47.636; -27.527
Faraday[3] 50623 49°42′40″N 28°38′10″W / 49.711°N 28.636°W / 49.711; -28.636
Charlie-Gibbs[3] 2000350[2] 52°37′26″N 33°11′53″W / 52.624°N 33.198°W / 52.624; -33.198
Bight[3] 33623 56°43′16″N 33°47′31″W / 56.721°N 33.792°W / 56.721; -33.792
Jan Mayen[3] 374211 71°22′19″N 9°24′18″E / 71.372°N 9.405°E / 71.372; 9.405
Greenland (to the west)[7]0 36574°02′N 8°49′E / 74.04°N 8.82°E / 74.04; 8.82
Senja (to the east)[7]039874°02′N 8°49′E / 74.04°N 8.82°E / 74.04; 8.82

Fracture zones involved in the early opening of the North Atlantic[8]

American side African side
Newfoundland Fracture Zone[9]
Kelvin Fracture ZoneCanary Fracture Zone
Cape Fear Fracture ZoneCape Verde Fracture Zone
Bahama Fracture ZoneGuinea Fracture Zone

Mid-Atlantic Ridge (Southern Hemisphere)

Name Minimum length
in km 		Length of
transform fault in km		 Position at Ridge
Romanche[3] 2445 950 0°29′S 20°29′W / 0.49°S 20.49°W / -0.49; -20.49
Chain[3]13152691°12′47″S 14°13′44″W / 1.213°S 14.229°W / -1.213; -14.229
Ascension[3]11492646°55′41″S 12°16′59″W / 6.928°S 12.283°W / -6.928; -12.283
Bode Verde[3]301823211°41′10″S 13°56′10″W / 11.686°S 13.936°W / -11.686; -13.936
Cardno[3]16498714°04′34″S 14°03′22″W / 14.076°S 14.056°W / -14.076; -14.056
Tetyaev[3]81012216°16′16″S 13°43′08″W / 16.271°S 13.719°W / -16.271; -13.719
Saint Helena[3]11841916°37′01″S 14°20′38″W / 16.617°S 14.344°W / -16.617; -14.344
Hotspur[3]144611317°43′16″S 13°19′44″W / 17.721°S 13.329°W / -17.721; -13.329
Martin Vaz[3]13242618°35′38″S 12°37′59″W / 18.594°S 12.633°W / -18.594; -12.633
Rio Grande[3]177415629°04′52″S 13°04′01″W / 29.081°S 13.067°W / -29.081; -13.067
Tristan Da Cunha[3]10142638°23′17″S 16°47′46″W / 38.388°S 16.796°W / -38.388; -16.796
Gough[3]10574240°38′13″S 16°38′13″W / 40.637°S 16.637°W / -40.637; -16.637
Conrad (to the west)[3]316055°11′06″S 0°07′59″W / 55.185°S 0.133°W / -55.185; -0.133
Bouvet (to the east)[3]198055°11′06″S 0°07′59″W / 55.185°S 0.133°W / -55.185; -0.133

Indian Ocean

Southwest Indian Ridge

Carlsberg Ridge

Central Indian Ridge

Lakshadweeo-Chagos Ridge

Southern Ocean

References

  1. ↑ Gilman, Larry; Lerner, K. Lee. "Mid-Ocean-Ridges". Water Encyclopedia. Retrieved 2011-11-29.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 Müller, R. Dietmar; Roest, Walter R. (1992). "Fracture Zones in the North Atlantic from Combined Geosat and Seasat Data" (PDF). Journal of Geophysical Research. 97 (B3): 3337–3350. Bibcode:1992JGR....97.3337M. doi:10.1029/91JB02605. Retrieved 2011-11-30.
  3. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 Name from GEBCO gazetteer, position refined by means of etopo2 and sample data of GPlates
  4. ↑ Udintsev, G.B. (1996). "Equatorial Segment of the Mid-Atlantic Ridge" (PDF). Unesco. Retrieved 2011-12-05.
  5. 1 2 3 Roest, W. R.; Collette, B. J. (1986). "The Fifteen Twenty Fracture Zone and the North American - South American plate boundary". Journal of the Geological Society. 143: 833–843. doi:10.1144/gsjgs.143.5.0833.
  6. ↑ Tucholke, Brian E.; Schouten, Hans (1988-03-01). "Kane Fracture Zone". Marine Geophysical Research. 10: 1–39. Bibcode:1988MarGR..10....1T. doi:10.1007/BF02424659.
  7. 1 2 "Map with Jan Mayen, Greenland and Senja Fracture Zones". Ocean Drilling Project. Retrieved 2011-12-16.
  8. ↑ Le Pichon, Xavier; Fox, Paul J. (1971-09-10). "Marginal Offsets, Fracture Zones, and the Early Opening of the North Atlantic". Journal of Geophysical Research. 76 (26): 6294–6308. Bibcode:1971JGR....76.6294L. doi:10.1029/JB076i026p06294.
  9. ↑ Auzende, J.M.; Olivet, J.L.; Bonnin, J. (1970). "Marge du Grand Bank et la fracture de Terre-Neuve". Compt. Rend. (in French). 271: 1063–1066.
  10. 1 2 3 Patriat, P., Sauter, D., Munschy, M., & Parson, L. (1997). A survey of the Southwest Indian Ridge axis between Atlantis II Fracture Zone and the Indian Ocean Triple Junction: Regional setting and large scale segmentation. Marine Geophysical Researches, 19(6), 457-480.
Sources
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