52:
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Up to 2.2 million years ago the Vema transform fault was 40 km shorter than today, and the Lema fracture zone had a leftward offset of 40 km. Then the old spreading valley between Lema and Vema died, and spreading started from an axis 40 km to the east. The Vema transform was thus
228:
extended by 40 km, while the Lema fracture zone was reduced to zero offset. Spreading from the new axis has meanwhile increased the distance between the old and the new axis to 80 km.
402:; Honnorez, J.; Lagabrielle, Y.; Malavieille, J.; Mamaloukas-Frangoulis, V.; Mével, C. (1990). "The MAR-Vema Fracture Zone intersection surveyed by deep submersible Nautile".
249:
Kastens, K.; Bonatti, E.; Caress, D.; Carrara, G.; Dauteuil, O.; Frueh-Green, G.; Ligi, M.; Tartarotti, P. (1998). "The Vema
Transverse Ridge (Central Atlantic)".
187:
system. This narrow ridge must have risen as a single vertical slab 6.6 million years ago. Up to three million years ago the ridge was at or even above
211:-shaped profile, the next fracture zone to the south has a steep vertical wall on its southern side rising from a horizontal valley bottom. As an
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21:
145:. The fault was subsequently explored by the French research vessel Jean Charcot in 1977 using its SeaBeam Classic
439:
292:
Heezen, B. C.; Gerard, R. D.; Tharp, M. (1964). "The Vema
Fracture Zone in the Equatorial Atlantic".
219:
ema
Fracture Zone. The north–south distance between the Vema and Lema fracture zones is 70 km.
114:, with additional surveying taking place in the years 1959–1960. In the 1960s research was done by
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The southern wall of the transform valley is crowned by one of the longest and highest transverse
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115:
361:"The Vema fracture zone and the tectonics of transverse shear zones in oceanic crustal plates"
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has a depth of 5000m. The fracture zone can be traced for over 2500 km east to west.
8:
134:
16:
Fracture zone in the equatorial
Atlantic which offsets the Mid-Atlantic Ridge to the left
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262:
415:
380:
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already suspected that there should be a passage through the Mid-Atlantic Ridge around
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9 North. The Vema
Fracture Zone was then discovered in 1956 by G.R. Hamilton on board
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in 1998, making it one of the world's best surveyed seafloor features.
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van Andel, Tjeerd H.; Herzen, Richard P.; Phillips, J.D. (1971).
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From temperature data gathered from the deep ocean on the
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would fit in well here, this fracture zone is nicknamed
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336:"History of Woods Hole Oceanographic Institution"
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398:Auzende, J. M.; Bideau, D.; Bonatti, E.;
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340:Woods Hole Oceanographic Institution
195:to its present depth of 450 meters.
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416:10.1111/j.1365-3121.1990.tb00038.x
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203:While the transform valley of the
14:
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83:by 320 km to the left. Its
294:Journal of Geophysical Research
55:Vema Fracture Zone, full extent
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1:
365:Marine Geophysical Researches
251:Marine Geophysical Researches
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167:in 1993, and the Russian RV
7:
10:
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169:Akademik Nikolay Strakhov
160:RV Nadir in 1989, the US
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207:ema Fracture Zone has a
97:German Meteor expedition
314:10.1029/JZ069i004p00733
271:10.1023/A:1004745127999
64:
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147:multibeam echosounder
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63:Vema transform fault
306:1964JGR....69..733H
263:1998MarGR..20..533K
91:Exploration history
33: /
440:Mid-Atlantic Ridge
377:10.1007/BF00338257
199:Lema Fracture Zone
81:Mid-Atlantic Ridge
75:in the equatorial
69:Vema Fracture Zone
65:
57:
120: (T-AGOR-10)
118:Thomas Washington
79:. It offsets the
37:10.726°N 42.333°W
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175:Transverse ridge
143: (T-AGOR-3)
141:Robert D. Conrad
85:transform valley
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185:mid-ocean ridge
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42:10.726; -42.333
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435:Fracture zones
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371:(3): 261–283.
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183:of the entire
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77:Atlantic Ocean
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164:Maurice Ewing
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149:, the French
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73:fracture zone
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343:. Retrieved
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191:. Later it
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99:(1925–1927)
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68:
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151:submersible
126:Atlantis II
40: /
429:Categories
404:Terra Nova
400:Cannat, M.
345:2012-01-28
300:(4): 733.
257:(6): 533.
223:Ridge jump
158:mothership
139:USNS
116:USNS
101:Georg Wüst
28:42°19′59″W
25:10°43′34″N
410:: 68–73.
385:128784529
322:130845561
279:126837679
193:subsided
189:sealevel
162:RV
156:and its
131:RV Chain
124:RV
109:RV
105:latitude
302:Bibcode
259:Bibcode
154:Nautile
135:RV Argo
383:
320:
277:
181:ridges
381:S2CID
318:S2CID
275:S2CID
232:Notes
71:is a
137:and
111:Vema
67:The
412:doi
373:doi
310:doi
267:doi
431::
406:.
379:.
367:.
363:.
338:.
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298:69
296:.
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255:20
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239:^
133:,
129:,
122:,
418:.
414::
408:2
387:.
375::
369:1
348:.
324:.
312::
304::
281:.
269::
261::
217:L
213:L
209:V
205:V
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