32:
39:
349:
This fault which ruptured lays perpendicular to the fracture zones which extend south from the plate boundary between the
Antarctic and Australian Plates, and it intersects almost perpendicularly with both the CFZ and the GFZ. These two intersections were found to be the areas of highest stress along
345:
5000 years ago were consistent with the rupture pattern that occurred. Therefore, it is hypothesised that these post-glacial stresses ruptured the crust at a pre-existing zone of crustal weakness. It was found that the area which ruptured was the dead normal fault just to the north of the APES, which
328:
manner, oriented east-west for a length of roughly 200 km (124 mi). The event comprised five separate subevents, which were clustered into two regions. The first three subevents occurred during the first 50 seconds of the rupture, and extended roughly 100 km (62 mi) to the west of
370:
After the
Balleny Islands earthquake, the seismicity of a wide area surrounding the epicentre was measurably changed, with an increase in detected earthquakes extending as far as into the Antarctic continent itself. It was not able to be determined if this increased detection was directly the result
366:
within the 12 months after the earthquake occurred, of which 54 of them occurred within the first month. The largest aftershock was a magnitude 6.4 which struck 9 hours after the main shock. These aftershocks were also clustered around the intersections between the ruptured fault and the fracture
336:
were not consistent with the rupture pattern that was observed. Therefore, the earthquake must have been caused by other processes. It was found that the stresses which would be generated within the
Antarctic Plate as a result of the
300:
within the tectonic plates are created as continuations of these transform faults. Two of the fracture zones that extend south from the plate boundary are the Carey
Fracture Zone (CFZ) and the Gambier Fracture Zone (GFZ).
312:, in addition to two more faults just to the north of the seamount. It is hypothesised that these dead normal faults were created during the initial rifting of the Antarctic and Australian Plates.
324:
of 8.1, with its epicentre being located roughly 250 km (155 mi) south of the boundary between the
Antarctic and Australian Plates. The earthquake ruptured in a sinistral (left lateral)
257:. The earthquake occurred in an area which previously had very little seismic activity, and so such a large event was unprecedented in the seismic record.
245:. Due to the remote location of the earthquake, there were no reports of anyone feeling any shaking or any damage being caused. The event was a complex
329:
the epicentre. The last two subevents occurred during seconds 70 to 90, and ruptured an area roughly 200 km (124 mi) west of the epicentre.
31:
148:
818:
350:
the fault which ruptured, and consequently the two subevent clusters which occurred were located nearby to these two intersections.
580:"Re-visiting the tectonics of the oceanic intraplate earthquake of March 25, 1998 (M 8.1) in the Balleny sea, offshore Antarctica"
916:
359:
761:"Statistical analysis of seismicity in a wide region around the 1998 Mw 8.1 Balleny Islands earthquake in the Antarctic Plate"
253:. To date it is the largest recorded earthquake in Antarctica, and is the largest recorded earthquake to have been caused by
304:
Also located in the region is the
Antarctic Plate Earthquake Seamount (APES), named after the associated event. Within this
853:
844:
62:
811:
501:"What Caused the March 25, 1998 Antarctic Plate Earthquake?: Inferences from Regional Stress and Strain Rate Fields"
907:
892:
76:
871:
990:
901:
430:
285:, and so stresses are imparted into the interiors of the plates themselves rather than only at the boundaries.
940:
804:
719:
985:
833:
830:
827:
405:
380:
282:
500:
1000:
922:
385:
51:
579:
123:
980:
333:
266:
995:
934:
346:
was reactivated and ruptured in a strike-slip manner upon being imparted with horizontal stresses.
928:
883:
321:
226:
81:
68:
622:"Seafloor structure near the epicenter of the great 25 March 1998 Antarctic Plate earthquake"
325:
246:
183:
595:
772:
685:
633:
591:
512:
468:
332:
Studies found that the stresses imparted into the interior of the
Antarctic Plate from the
254:
8:
720:"The March 25, 1998 Antarctic Earthquake: Great earthquake caused by postglacial rebound"
674:"The great March 25, 1998, Antarctic Plate earthquake: Moment tensor and rupture history"
342:
776:
689:
637:
516:
472:
741:
651:
528:
289:
112:
107:
655:
745:
780:
731:
693:
641:
599:
546:
532:
520:
476:
371:
of the
Balleny Islands earthquake, or if it was the result of improved technology.
274:
296:
are offset from each other and separated by small sections of transform faulting.
309:
293:
270:
250:
238:
785:
760:
603:
457:"Recent Oceanic Intraplate Earthquake in Balleny Sea Was Largest Ever Detected"
230:
974:
297:
278:
234:
163:
150:
338:
796:
698:
673:
524:
736:
646:
621:
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233:. Its epicentre was located roughly 450 km (280 mi) north of
193:
481:
456:
718:
Tsuboi, S.; Kikuchi, M.; Yamanaka, Y.; Kanao, M. (10 December 1999).
305:
367:
zones, and some even occurred on the fracture zones themselves.
281:
Plates meet. This junction lays nearby to the
Australia-Pacific
288:
The boundary between the
Antarctic and Australian Plates is
455:
Wiens, D. A.; Wysession, M. E.; Lawver, L. (28 July 1998).
717:
225:
In the afternoon of Wednesday 25 March 1998, a very large
237:
and roughly 700 km (435 mi) northwest of the
38:
320:
The earthquake occurred at a shallow depth and had a
958:
indicates earthquake resulting in at least 30 deaths
454:
759:Himeno, T.; Kanao, M.; Ogata, Y. (December 2011).
672:Henry, C.; Das, S.; Woodhouse, H. (10 July 2000).
671:
972:
758:
308:, there are a series of east-west oriented dead
963:indicates the deadliest earthquake of the year
16:Earthquake off the coast of Antarctica in 1998
812:
626:Journal of Geophysical Research: Solid Earth
577:
461:Eos, Transactions American Geophysical Union
826:
498:
229:8.1 earthquake struck a remote area of the
819:
805:
499:Kreemer, C.; Holt, W. E. (1 August 2000).
784:
735:
697:
645:
619:
480:
124:
431:"NCEI Global Historical Hazard Database"
547:"Transform Faults & Fracture Zones"
973:
578:Gangopadhyay, A. (30 September 2006).
800:
265:Nearby to the Balleny Islands is the
713:
711:
709:
667:
665:
615:
613:
573:
571:
569:
567:
494:
492:
353:
584:Earth and Planetary Science Letters
260:
13:
14:
1012:
706:
662:
610:
564:
489:
620:Yoshifumi, N. (3 January 2013).
406:"M 8.1 - Balleny Islands region"
37:
30:
752:
678:Journal of Geophysical Research
292:. At divergent boundaries, the
22:1998 Balleny Islands earthquake
539:
448:
423:
398:
1:
391:
315:
505:Geophysical Research Letters
7:
868:Ryukyu Islands (7.5, May 4)
786:10.1016/j.polar.2011.08.002
381:List of earthquakes in 1998
374:
10:
1017:
604:10.1016/j.epsl.2006.07.030
386:2004 Tasman Sea earthquake
953:
840:
334:Macquarie Triple Junction
267:Macquarie Triple Junction
215:
207:
199:
189:
179:
142:
134:
118:
102:
87:
74:
61:
50:
26:
596:2006E&PSL.249..456G
138:8.7 km (5 mi)
249:earthquake within the
991:Geology of Antarctica
699:10.1029/2000JB900077
525:10.1029/1999GL011188
255:post-glacial rebound
831:Earthquakes in 1998
777:2011PolSc...5..421H
724:Earth Planets Space
690:2000JGR...10516097H
684:(B7): 16097–16118.
638:2013JGRB..118...13N
517:2000GeoRL..27.2297K
473:1998EOSTr..79..353W
410:earthquake.usgs.gov
343:Antarctic ice sheet
160: /
57:1998-03-25 03:12:25
23:
986:1998 in Antarctica
737:10.1186/BF03351621
647:10.1002/jgrb.50059
164:62.877°S 149.527°E
21:
1001:March 1998 events
968:
967:
917:Bahía de Caráquez
511:(15): 2297–2300.
482:10.1029/98EO00265
435:www.ngdc.noaa.gov
354:Subsequent events
223:
222:
1008:
981:1998 earthquakes
908:Papua New Guinea
821:
814:
807:
798:
797:
791:
790:
788:
756:
750:
749:
739:
715:
704:
703:
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669:
660:
659:
649:
617:
608:
607:
590:(3–4): 456–466.
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551:www.columbia.edu
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322:moment magnitude
294:spreading ridges
283:pole of rotation
261:Tectonic setting
175:
174:
172:
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170:
169:-62.877; 149.527
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161:
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129:
98:
96:
41:
40:
34:
24:
20:
1016:
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1009:
1007:
1006:
1005:
996:Balleny Islands
971:
970:
969:
964:
959:
949:
872:2nd Afghanistan
863:Balleny Islands
854:1st Afghanistan
845:Zhangbei-Shanyi
836:
825:
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707:
670:
663:
618:
611:
576:
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555:
553:
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467:(30): 353–354.
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428:
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251:Antarctic Plate
239:Balleny Islands
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103:Local time
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88:Local date
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947:
943:(7.7, Nov 29)
938:
932:
926:
920:
914:
910:(7.0, Jul 17)
905:
902:Azores Islands
899:
895:(6.3, Jun 27)
890:
881:
874:(6.5, May 30)
869:
866:
860:
851:
847:(5.7, Jan 10)
841:
838:
837:
824:
823:
816:
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792:
771:(4): 421–431.
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730:(2): 133–136.
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298:Fracture zones
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231:Southern Ocean
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190:Areas affected
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984:
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937:(6.2, Nov 19)
936:
933:
931:(5.5, Sep 29)
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927:
925:(5.2, Sep 25)
924:
921:
918:
915:
913:
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906:
903:
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898:
894:
891:
889:
886:(6.6 May 22)
885:
882:
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877:
873:
870:
867:
865:(8.1, Mar 25)
864:
861:
859:
856:(6.1, Feb 4)
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765:Polar Science
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310:normal faults
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91:25 March 1998
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60:
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53:
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33:
25:
19:
960:
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944:
941:North Maluku
919:(7.2, Aug 4)
911:
904:(6.2, Jul 9)
896:
893:Adana–Ceyhan
887:
878:
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862:
857:
848:
768:
764:
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727:
723:
681:
677:
632:(1): 13–21.
629:
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583:
554:. Retrieved
550:
541:
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464:
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438:. Retrieved
434:
425:
413:. Retrieved
409:
400:
369:
362:reported 68
357:
348:
339:deglaciation
331:
319:
303:
287:
269:, where the
264:
224:
200:Total damage
18:
364:aftershocks
326:strike-slip
208:Aftershocks
184:Strike-slip
167: /
155:149°31′37″E
65: event
975:Categories
923:Pymatuning
556:30 October
440:29 October
415:29 October
392:References
316:Earthquake
275:Australian
247:intraplate
243:Antarctica
216:Casualties
194:Antarctica
152:62°52′37″S
95:1998-03-25
54: time
656:140154927
290:divergent
271:Antarctic
227:magnitude
143:Epicenter
119:Magnitude
111:15:12:25
106:13:12:25
935:Ninglang
746:55625716
375:See also
306:seamount
929:Mionica
884:Aiquile
773:Bibcode
686:Bibcode
634:Bibcode
592:Bibcode
533:7505945
513:Bibcode
469:Bibcode
341:of the
279:Pacific
93: (
69:1083606
744:
654:
531:
277:, and
82:ComCat
742:S2CID
652:S2CID
529:S2CID
135:Depth
75:USGS-
558:2021
442:2021
417:2021
360:NEIC
358:The
219:None
211:Yes
203:None
180:Type
122:8.1
113:NZST
108:AEST
77:ANSS
781:doi
732:doi
694:doi
682:105
642:doi
630:118
600:doi
588:249
521:doi
477:doi
241:in
63:ISC
52:UTC
977::
779:.
767:.
763:.
740:.
728:52
726:.
722:.
708:^
692:.
680:.
676:.
664:^
650:.
640:.
628:.
624:.
612:^
598:.
586:.
582:.
566:^
549:.
527:.
519:.
509:27
507:.
503:.
491:^
475:.
465:79
463:.
459:.
433:.
408:.
273:,
961:‡
956:†
945:†
912:†
897:†
888:†
879:‡
876:†
858:†
849:†
834:→
828:←
820:e
813:t
806:v
789:.
783::
775::
769:5
748:.
734::
702:.
696::
688::
658:.
644::
636::
606:.
602::
594::
560:.
535:.
523::
515::
485:.
479::
471::
444:.
419:.
127:w
125:M
97:)
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