List of fracture zones

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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 fracture 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′24″S 104°37′3″W / 35.54000°S 104.61750°W / -35.54000; -104.61750
1,750 (1,090) 50 (30) 42°59′43″S 83°11′5″W / 42.99528°S 83.18472°W / -42.99528; -83.18472
50 (30) 45°54′29″S 76°25′31″W / 45.90806°S 76.42528°W / -45.90806; -76.42528
0
0 49°06′47″S 80°12′33″W / 49.11306°S 80.20917°W / -49.11306; -80.20917
1,550 (960) 280 (170) 44°47′55″S 80°15′53″W / 44.79861°S 80.26472°W / -44.79861; -80.26472
1,300 (810) 70 (40) 45°44′7″S 77°27′32″W / 45.73528°S 77.45889°W / -45.73528; -77.45889
0
Mocha 450 (280) 0 39°14′24″S 77°22′59″W / 39.24000°S 77.38306°W / -39.24000; -77.38306
0
0
Valdivia 2,100 (1,300) 650 (400) 41°23′25″S 87°23′36″W / 41.39028°S 87.39333°W / -41.39028; -87.39333

East Pacific Rise[]

Name Minimum length
in km		 Length as plate
boundary in km		 Coordinates
Easter
0
0 19°49′28″S 77°35′53″W / 19.82444°S 77.59806°W / -19.82444; -77.59806
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
[3] 1451 454 0°39′40″N 27°55′52″W / 0.661°N 27.931°W / 0.661; -27.931
[3] 333 40 2°31′55″N 31°00′29″W / 2.532°N 31.008°W / 2.532; -31.008
[3] (formerly:Four North[4]) 1814 100 3°55′59″N 32°06′58″W / 3.933°N 32.116°W / 3.933; -32.116
[3] 1111 52 6°13′48″N 33°35′17″W / 6.230°N 33.588°W / 6.230; -33.588
[3] 173 84 7°08′06″N 34°21′04″W / 7.135°N 34.351°W / 7.135; -34.351
[3] 194 107 7°41′35″N 37°28′59″W / 7.693°N 37.483°W / 7.693; -37.483
[3] 381 144 8°07′08″N 38°45′00″W / 8.119°N 38.750°W / 8.119; -38.750
[3] 691 99 8°51′18″N 39°56′17″W / 8.855°N 39.938°W / 8.855; -39.938
Vema[3] 822 300 10°43′34″N 42°19′59″W / 10.726°N 42.333°W / 10.726; -42.333
[5] 39 12°07′55″N 43°55′26″W / 12.132°N 43.924°W / 12.132; -43.924
[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]		 1195 195[5] 15°19′12″N 45°52′16″W / 15.320°N 45.871°W / 15.320; -45.871
[2] 50 17°49′55″N 46°35′20″W / 17.832°N 46.589°W / 17.832; -46.589
[2] 30 18°32′28″N 46°27′54″W / 18.541°N 46.465°W / 18.541; -46.465
[2] 24 18°58′01″N 46°07′41″W / 18.967°N 46.128°W / 18.967; -46.128
[2] 41 20°36′58″N 45°45′22″W / 20.616°N 45.756°W / 20.616; -45.756
Kane[3] 1040 150[6] 23°43′05″N 45°34′59″W / 23.718°N 45.583°W / 23.718; -45.583
[2] 1040 9 25°41′20″N 45°11′35″W / 25.689°N 45.193°W / 25.689; -45.193
[2] 15 29°21′54″N 43°00′25″W / 29.365°N 43.007°W / 29.365; -43.007
[3] 843 66 30°04′05″N 42°22′19″W / 30.068°N 42.372°W / 30.068; -42.372
[2] 9 32°19′23″N 40°11′42″W / 32.323°N 40.195°W / 32.323; -40.195
[2] 13 33°03′32″N 39°37′41″W / 33.059°N 39.628°W / 33.059; -39.628
[3] 624 151 33°36′54″N 38°26′20″W / 33.615°N 38.439°W / 33.615; -38.439
[3] 751 148 35°08′56″N 35°33′43″W / 35.149°N 35.562°W / 35.149; -35.562
21 36°38′28″N 33°27′50″W / 36.641°N 33.464°W / 36.641; -33.464
(to the west)[2][3] 719 67 37°28′05″N 31°53′56″W / 37.468°N 31.899°W / 37.468; -31.899
(to the east)[2][3] 758 67 37°28′05″N 31°53′56″W / 37.468°N 31.899°W / 37.468; -31.899
[3] 174 20 40°32′13″N 29°27′22″W / 40.537°N 29.456°W / 40.537; -29.456
[3] 74 9 40°32′13″N 29°27′22″W / 40.537°N 29.456°W / 40.537; -29.456
[3] 21 47°38′10″N 27°31′37″W / 47.636°N 27.527°W / 47.636; -27.527
[3] 506 23 49°42′40″N 28°38′10″W / 49.711°N 28.636°W / 49.711; -28.636
Charlie-Gibbs[3] 2000 350[2] 52°37′26″N 33°11′53″W / 52.624°N 33.198°W / 52.624; -33.198
[3] 336 23 56°43′16″N 33°47′31″W / 56.721°N 33.792°W / 56.721; -33.792
[3] 374 211 71°22′19″N 9°24′18″E / 71.372°N 9.405°E / 71.372; 9.405
(to the west)[7] 0 365 74°02′N 8°49′E / 74.04°N 8.82°E / 74.04; 8.82
(to the east)[7] 0 398 74°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[]

American side African side
Hudson Fracture Zone
Snorri Fracture Zone
Cartwright Fracture Zone
Julian Haab Fracture Zone
Minna Fracture Zone
Leif Fracture Zone
Newfoundland Fracture Zone[8]
Kelvin Fracture Zone[9] Canary Fracture Zone[9]
Cape Fear Fracture Zone[9] Cape Verde Fracture Zone[9]
Bahama Fracture Zone[9] Guinea Fracture Zone[9]

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
[3] 1315 269 1°12′47″S 14°13′44″W / 1.213°S 14.229°W / -1.213; -14.229
[3] 1149 264 6°55′41″S 12°16′59″W / 6.928°S 12.283°W / -6.928; -12.283
[3] 3018 232 11°41′10″S 13°56′10″W / 11.686°S 13.936°W / -11.686; -13.936
[3] 1649 87 14°04′34″S 14°03′22″W / 14.076°S 14.056°W / -14.076; -14.056
[3] 810 122 16°16′16″S 13°43′08″W / 16.271°S 13.719°W / -16.271; -13.719
[3] 1184 19 16°37′01″S 14°20′38″W / 16.617°S 14.344°W / -16.617; -14.344
[3] 1446 113 17°43′16″S 13°19′44″W / 17.721°S 13.329°W / -17.721; -13.329
[3] 1324 26 18°35′38″S 12°37′59″W / 18.594°S 12.633°W / -18.594; -12.633
[3] 1774 156 29°04′52″S 13°04′01″W / 29.081°S 13.067°W / -29.081; -13.067
[3] 1014 26 38°23′17″S 16°47′46″W / 38.388°S 16.796°W / -38.388; -16.796
[3] 1057 42 40°38′13″S 16°38′13″W / 40.637°S 16.637°W / -40.637; -16.637
Conrad (to the west)[3] 316 0 55°11′06″S 0°07′59″W / 55.185°S 0.133°W / -55.185; -0.133
Bouvet (to the east)[3] 198 0 55°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. ^ Jump up to: a b c d e f g h i j k l 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): 3337–50. Bibcode:1992JGR....97.3337M. doi:10.1029/91JB02605. Archived from the original (PDF) on 2012-03-28. Retrieved 2011-11-30.
  3. ^ Jump up to: a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak 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". Unesco. Archived from the original on 2012-09-07. Retrieved 2011-12-05.
  5. ^ Jump up to: a b c 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: 833–43. 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. ^ Jump up to: a b "Map with Jan Mayen, Greenland and Senja Fracture Zones". Ocean Drilling Project. Retrieved 2011-12-16.
  8. ^ Auzende, J.M.; Olivet, J.L.; Bonnin, J. (1970). "Marge du Grand Bank et la fracture de Terre-Neuve". Compt. Rend. (in French). 271: 1063–66.
  9. ^ Jump up to: a b c d e f 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): 6294–308. Bibcode:1971JGR....76.6294L. doi:10.1029/JB076i026p06294.
  10. ^ Jump up to: a b c 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), 457–80.
Sources
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