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[edit]

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[edit]

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[edit]

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[edit]

Juan de Fuca and Gorda Ridges[edit]

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[edit]

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)[edit]

Name Minimum length
in km
Length of
transform fault in km
Position at Ridge
Saint Paul[3] 1451 454 0°39′40″N 27°55′52″W / 0.661°N 27.931°W / 0.661; -27.931
Saint Peter[3] 333 40 2°31′55″N 31°00′29″W / 2.532°N 31.008°W / 2.532; -31.008
Strakhov[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
Sierra Leone[3] 1111 52 6°13′48″N 33°35′17″W / 6.230°N 33.588°W / 6.230; -33.588
Bogdanov[3] 173 84 7°08′06″N 34°21′04″W / 7.135°N 34.351°W / 7.135; -34.351
Vernadsky[3] 194 107 7°41′35″N 37°28′59″W / 7.693°N 37.483°W / 7.693; -37.483
Doldrums[3] 381 144 8°07′08″N 38°45′00″W / 8.119°N 38.750°W / 8.119; -38.750
Arkhangelskiy[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
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]
1195 195[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] 1040 150[6] 23°43′05″N 45°34′59″W / 23.718°N 45.583°W / 23.718; -45.583
Northern[2] 1040 9 25°41′20″N 45°11′35″W / 25.689°N 45.193°W / 25.689; -45.193
Tyro[2] 15 29°21′54″N 43°00′25″W / 29.365°N 43.007°W / 29.365; -43.007
Atlantis[3] 843 66 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] 13 33°03′32″N 39°37′41″W / 33.059°N 39.628°W / 33.059; -39.628
Hayes[3] 624 151 33°36′54″N 38°26′20″W / 33.615°N 38.439°W / 33.615; -38.439
Oceanographer[3] 751 148 35°08′56″N 35°33′43″W / 35.149°N 35.562°W / 35.149; -35.562
Tydeman 21 36°38′28″N 33°27′50″W / 36.641°N 33.464°W / 36.641; -33.464
Pico (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
East Azores (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
Kurchatov[3] 174 20 40°32′13″N 29°27′22″W / 40.537°N 29.456°W / 40.537; -29.456
Petrov[3] 74 9 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] 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
Bight[3] 336 23 56°43′16″N 33°47′31″W / 56.721°N 33.792°W / 56.721; -33.792
Jan Mayen[3] 374 211 71°22′19″N 9°24′18″E / 71.372°N 9.405°E / 71.372; 9.405
Greenland (to the west)[7] 0 365 74°02′N 8°49′E / 74.04°N 8.82°E / 74.04; 8.82
Senja (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[8][edit]

American side African side
Newfoundland Fracture Zone[9]
Kelvin Fracture Zone Canary Fracture Zone
Cape Fear Fracture Zone Cape Verde Fracture Zone
Bahama Fracture Zone Guinea Fracture Zone

Mid-Atlantic Ridge (Southern Hemisphere)[edit]

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] 1315 269 1°12′47″S 14°13′44″W / 1.213°S 14.229°W / -1.213; -14.229
Ascension[3] 1149 264 6°55′41″S 12°16′59″W / 6.928°S 12.283°W / -6.928; -12.283
Bode Verde[3] 3018 232 11°41′10″S 13°56′10″W / 11.686°S 13.936°W / -11.686; -13.936
Cardno[3] 1649 87 14°04′34″S 14°03′22″W / 14.076°S 14.056°W / -14.076; -14.056
Tetyaev[3] 810 122 16°16′16″S 13°43′08″W / 16.271°S 13.719°W / -16.271; -13.719
Saint Helena[3] 1184 19 16°37′01″S 14°20′38″W / 16.617°S 14.344°W / -16.617; -14.344
Hotspur[3] 1446 113 17°43′16″S 13°19′44″W / 17.721°S 13.329°W / -17.721; -13.329
Martin Vaz[3] 1324 26 18°35′38″S 12°37′59″W / 18.594°S 12.633°W / -18.594; -12.633
Rio Grande[3] 1774 156 29°04′52″S 13°04′01″W / 29.081°S 13.067°W / -29.081; -13.067
Tristan Da Cunha[3] 1014 26 38°23′17″S 16°47′46″W / 38.388°S 16.796°W / -38.388; -16.796
Gough[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[edit]

Carlsberg Ridge[edit]

Central Indian Ridge[edit]

Lakshadweeo-Chagos Ridge[edit]

Southern Ocean[edit]

References[edit]

  1. ^ Gilman, Larry; Lerner, K. Lee. "Mid-Ocean-Ridges". Water Encyclopedia. Retrieved 2011-11-29. 
  2. ^ 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". Journal of Geophysical Research 97 (B3): 3337–3350. Bibcode:1992JGR....97.3337M. doi:10.1029/91JB02605. Retrieved 2011-11-30. 
  3. ^ 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. Retrieved 2011-12-05. 
  5. ^ 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: 833–843. 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. ^ a b "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. 
Sources