189:). The VTZ corresponds with a part of the Mariana Trough where the crust thickens from 6 to 15 km. The southern VTZ is dominated by fissure eruptions associated with a ridge-like feature, ~30 km long, which rises to less than 2800 m water depth and which is similar to the inflated segment at the southern terminus of the spreading ridge. The northern VTZ is dominated by point-source volcanism, with edifices spaced 50–60 km apart alternating with rift basins. There is no volcanic activity along the adjacent arc segment and it appears that the extension axis has captured the arc magma supply between the Kasuga cross-chain at 22°N and Nikko near 23°N, where the extension axis intersects the arc. North of this, incipient rifting is magmatically manifested by unusual,
79:. It narrows northward until the Mariana arc and West Mariana Ridge meet at about 24°N. It is widest in the middle, at 18°N, where it is about 240 km wide, and narrows to about half this at its southern, open end. Depths in the basin are distributed asymmetrically, being greater adjacent to the West Mariana Ridge than next to the active arc, due to a westward-thinning wedge of volcaniclastic sediments derived from the active arc, and also less thermal buoyancy of the
17:
103:
62:
The
Mariana Trough stretches 1300 km from north to south, about the distance from Los Angeles CA to Portland OR, Tokyo, Japan to Seoul, Korea, or London, England to Rome, Italy. The Mariana Trough has roughly the dimensions and areal extent of Japan or
209:), so the variations in tectonic and magmatic style seen along-strike north of 18°N provide an example of the sequence of events that occur at any one section across the back-arc basin as the rift evolves from updoming through rifting to true spreading.
165:). These basins have low heatflow, lack igneous activity, and are the deepest parts of the Mariana Trough (>5400 m). The deepest part of the Central Graben is also unique among active
145:
that is sometimes occupied by a central ridge where volcanic activity is concentrated (neovolcanic zone); south of this the ridge more resembles a fast-spreading ridge, probably because
380:
Stern, R.J.; Bloomer, S.H.; Martinez, F.; Yamazaki, T.; Harrison, T.M. (1996). "The composition of back-arc basin lower crust and upper mantle in the
Mariana Trough: A first report".
67:. The Trough is crudely crescent-shaped, opening on the south; it is bounded to the east by the active Mariana arc, to the west by the remnant arc of the West Mariana Ridge (
349:
Park, C.-H.; Tamaki, K.; Kobayashi, K. (1990). "Age-depth correlation of the
Philippine Sea back-arc basins and other marginal basins in the world".
157:). The ridge becomes punctiform north of 18°30', and true seafloor spreading does not occur north of 19°45'N (but see the different conclusion of
401:
Stern, R.J.; Fouch, M.J.; Klemperer, S. (2003). "An
Overview of the Izu–Bonin–Mariana Subduction Factory". In J. Eiler; M. Hirschmann (eds.).
141:. From as far north as 19°45'N south to 13°10’N, the spreading ridge has the typical morphology of a slow-spreading ridge, with an axial
463:
95:, including the Mariana Trough, lies at a mean depth of 3200 m compared to normal zero-age seafloor depths of 2500 m (
415:
285:
Martinez, F.; Fryer, P.; Baker, N.A.; Yamazaki, T. (1995). "Evolution of
Backarc Rifting: Mariana Trough, 20°-24°N".
51:
425:
Yamazaki, T.; Murakami, F.; Saito, E. (1993). "Mode of seafloor spreading in the northern
Mariana Trough".
269:
31:
185:
processes that are distinct from seafloor spreading, in a region known as the
Volcano-Tectonic Zone (VTZ;
113:
and data bases (Smith and
Sandwell and Smith global measured and predicted bathymetry file topo_9.1.img,
205:). Rifting and spreading are inferred to be propagating northward at a rate of 10 to 40 cm/year (
161:). Rifting forms a series of amagmatic deeps between 19°45'N and 21°10'N called the 'Central Graben' (
153:). Spreading half-rates in the region between 16° and 18°N are estimated at 1.5 to 2.2 cm/year (
468:
351:
106:
Bathymetry of the
Mariana Trough and surroundings. The figure was generated by Dr. F. Martinez
402:
434:
360:
327:
294:
257:
228:
219:
Bibee, L.D.; Shor Jr., G.G.; Lu, R.S. (1980). "Inter-arc spreading in the
Mariana Trough".
107:
8:
126:
438:
364:
331:
298:
261:
232:
393:
194:
134:
410:. Geophysical Monograph. Vol. 138. American Geophysical Union. pp. 175–222.
446:
411:
372:
273:
240:
130:
442:
389:
368:
335:
302:
265:
236:
80:
114:
72:
166:
92:
76:
43:
457:
316:"Geophysical characteristics of the southern Mariana Trough, 11°50'N-13°40'N"
277:
340:
315:
16:
26:
lies in the southern part of the IBM arc system in the Western Pacific.
190:
170:
88:
64:
306:
91:
more rugged than normal. The most recent, "zero-age" seafloor of the
84:
198:
182:
178:
138:
102:
142:
111:
177:). Extension north of the Central Graben occurs by combined
146:
379:
174:
27:
284:
206:
186:
162:
270:
10.1130/0016-7606(1972)83[1057:RA]2.0.CO;2
424:
158:
400:
348:
313:
202:
150:
96:
47:
133:into a southern two-thirds characterized by slow
455:
129:axis for the Mariana Trough can be subdivided
320:Journal of Geophysical Research: Solid Earth
314:Martinez, F.; Fryer, P.; Becker, N. (2000).
287:Journal of Geophysical Research: Solid Earth
149:supply is enhanced by proximity to the arc (
110:using open source software GMT version 4.14
218:
154:
57:
339:
101:
15:
456:
250:Geological Society of America Bulletin
137:and a northern third characterized by
247:
68:
248:Karig, D.E. (1972). "Remnant Arcs".
159:Yamazaki, Murakami & Saito 1993
13:
394:10.1111/j.1440-1738.1996.tb00036.x
120:
50:). It is an integral part of the
14:
480:
203:Stern, Fouch & Klemperer 2003
97:Park, Tamaki & Kobayashi 1990
48:Stern, Fouch & Klemperer 2003
151:Martinez, Fryer & Becker2000
46:in the western Pacific Ocean (
1:
404:Inside the Subduction Factory
212:
87:, the seafloor is deeper and
464:Geology of the Pacific Ocean
447:10.1016/0040-1951(93)90333-F
373:10.1016/0040-1951(90)90028-7
241:10.1016/0025-3227(80)90030-4
32:The Northern Mariana Islands
7:
71:), and to the south by the
10:
485:
173:along the extension axis (
155:Bibee, Shor & Lu 1980
193:of the Hiyoshi complex,
83:. Where not covered by
24: The Mariana Trough
197:(or Sin Iwo Jima), and
58:Location and Bathymetry
34:mark its eastern limit.
117:
35:
105:
52:Izu–Bonin–Mariana Arc
19:
341:10.1029/2000JB900117
108:University of Hawaii
439:1993Tectp.221..207Y
365:1990Tectp.181..351C
332:2000JGR...10516591M
299:1995JGR...100.3807M
262:1972GSAB...83.1057K
233:1980MGeol..35..183B
169:in exposing mantle
195:Fukutoku-oka-no-ba
135:seafloor spreading
118:
36:
307:10.1029/94JB02466
191:shoshonitic lavas
175:Stern et al. 1996
476:
450:
421:
409:
397:
376:
345:
343:
310:
281:
256:(4): 1057–1068.
244:
23:
484:
483:
479:
478:
477:
475:
474:
473:
469:Back-arc basins
454:
453:
418:
407:
326:: 16591–16607.
215:
207:Martinez et al.
187:Martinez et al.
167:back-arc basins
163:Martinez et al.
123:
121:Extension style
73:Challenger Deep
60:
25:
21:
12:
11:
5:
482:
472:
471:
466:
452:
451:
433:(2): 207–221.
427:Tectonophysics
422:
416:
398:
388:(3): 354–372.
377:
352:Tectonophysics
346:
311:
282:
245:
221:Marine Geology
214:
211:
122:
119:
93:Philippine Sea
77:Mariana Trench
75:, part of the
59:
56:
44:back-arc basin
40:Mariana Trough
20:
9:
6:
4:
3:
2:
481:
470:
467:
465:
462:
461:
459:
448:
444:
440:
436:
432:
428:
423:
419:
417:0-87590-997-3
413:
406:
405:
399:
395:
391:
387:
383:
378:
374:
370:
366:
362:
358:
354:
353:
347:
342:
337:
333:
329:
325:
321:
317:
312:
308:
304:
300:
296:
293:: 3807–3827.
292:
288:
283:
279:
275:
271:
267:
263:
259:
255:
251:
246:
242:
238:
234:
230:
226:
222:
217:
216:
210:
208:
204:
200:
196:
192:
188:
184:
180:
176:
172:
168:
164:
160:
156:
152:
148:
144:
140:
136:
132:
128:
115:
112:
109:
104:
100:
98:
94:
90:
86:
82:
78:
74:
70:
66:
55:
53:
49:
45:
42:is an active
41:
33:
29:
18:
430:
426:
403:
385:
381:
356:
350:
323:
319:
290:
286:
253:
249:
224:
220:
131:along strike
124:
61:
39:
37:
359:: 351–371.
227:: 183–197.
171:peridotites
458:Categories
382:Island Arc
213:References
89:bathymetry
69:Karig 1972
65:California
278:0016-7606
127:extension
85:sediments
199:Iwo Jima
183:magmatic
179:tectonic
54:system.
435:Bibcode
361:Bibcode
328:Bibcode
295:Bibcode
258:Bibcode
229:Bibcode
139:rifting
414:
276:
143:graben
81:mantle
22:
408:(PDF)
147:magma
412:ISBN
274:ISSN
181:and
125:The
38:The
30:and
28:Guam
443:doi
431:221
390:doi
369:doi
357:181
336:doi
324:105
303:doi
291:100
266:doi
237:doi
99:).
460::
441:.
429:.
384:.
367:.
355:.
334:.
322:.
318:.
301:.
289:.
272:.
264:.
254:83
252:.
235:.
225:35
223:.
449:.
445::
437::
420:.
396:.
392::
386:5
375:.
371::
363::
344:.
338::
330::
309:.
305::
297::
280:.
268::
260::
243:.
239::
231::
201:(
116:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
