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Since its discovery, the magnetic excursion has been demonstrated in geological archives from many parts of the world. The transition from the normal field to the reversed field lasted approximately 250 years, while the magnetic field remained reversed for approximately 440 years. During
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the transition, Earth's magnetic field declined to a minimum of 5% of its current strength, and was at about 25% of its current strength when fully reversed. This reduction in geomagnetic field strength resulted in more
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of many megafauna species, and the relatively moderate radio-isotopic changes during the event, have cast significant doubt on the real impact of the
Laschamp event on global environmental changes.
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The
Laschamp event was the first known geomagnetic excursion and remains the most thoroughly studied among the known geomagnetic excursions.
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Bonhommet, N.; Zähringer, J. (1969). "Paleomagnetism and potassium argon age determinations of the
Laschamp geomagnetic polarity event".
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The name derives from the
Laschamps lava flows from which it was discovered, but appears as 'Laschamp' in most scientific literature.
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286:
436:"A geomagnetic curveball 42,000 years ago changed our planet forever: The future is unpredictable—just ask the Neanderthals"
31:(a short reversal of the Earth's magnetic field). It occurred between 42,200 and 41,500 years ago, during the end of the
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reveals that the tree was alive from 42,500–41,000 years ago, within the timeframe of the event.
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310:"An extremely brief reversal of the geomagnetic field, climate variability, and a super volcano"
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35:. It was discovered from geomagnetic anomalies found in the Laschamps and Olby lava flows near
97:. However, the lack of corroborating evidence of a causal link between the Laschamp event and
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This loss of the geomagnetic shield is claimed to have contributed to the extinction of
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Because it occurred approximately 42,000 years ago, the period has been termed the
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312:(Press release). Helmholtz Association of German Research Centres. 16 October 2012
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75:
281:. Vol. 5 Geomagnetism (1st ed.). Elsevier Science. pp. 373–416.
407:"End of Neanderthals linked to flip of Earth's magnetic poles, study suggests"
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526:"The Adams Event, a geomagnetic-driven environmental crisis 42,000 years ago"
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253:
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600:"Ancient Northland kauri tree reveals secrets of Earth's polar reversal"
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230:"K–Ar and 40Ar/39Ar Age of the Laschamp geomagnetic polarity reversal"
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626:"Ancient trees show when the Earth's magnetic field last flipped out"
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71:
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Brief reversal of the Earth's magnetic field about 41,400 years ago
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The
Australian Research Council is funding research to analyze a
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that "42" was the answer to life, the universe and everything.
40:
60:
581:"A Hitchhiker's Guide to an Ancient Geomagnetic Disruption"
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387:"NZ's ancient kauri yields major scientific discovery"
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265:
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464:"Kauri trees mark magnetic flip 42,000 years ago"
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333:"A global environmental crisis 42,000 years ago"
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623:
270:Laj, C.; Channell, J.E.T. (27 September 2007).
331:Cooper, Alan; et al. (19 February 2021).
523:
269:
228:Hall, Chris M.; York, Derek (August 1978).
657:"Changing Name for Earth's Changing Poles"
624:Greenfieldboyce, Nell (18 February 2021).
82:, and changes in atmospheric circulation.
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545:
530:EGU General Assembly Conference Abstracts
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578:
524:Cooper, Alan; Turney, Chris (May 2020).
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434:Watson, Sara Kiley (24 February 2021).
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461:
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579:Mitchell, Alanna (18 February 2021).
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123:The Hitchhiker's Guide to the Galaxy
110:Adams Transitional Geomagnetic Event
63:, causing greater production of the
195:Earth and Planetary Science Letters
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14:
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462:Voosen, Paul (19 February 2021).
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547:10.5194/egusphere-egu2020-12314
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138:found in New Zealand in 2019.
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277:. In Schubert, Gerald (ed.).
272:"5.10 Geomagnetic Excursions"
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488:10.1126/science.371.6531.766
215:10.1016/0012-821x(69)90159-9
7:
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10:
710:
298:– via elsevier.com.
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89:, the extinction of the
349:10.1126/science.abb8677
207:1969E&PSL...6...43B
598:Piper, Denise (2019).
392:The New Zealand Herald
279:Treatise on Geophysics
99:population bottlenecks
93:and the appearance of
50:Background and effects
636:National Public Radio
29:geomagnetic excursion
689:Geomagnetic reversal
645:– via NPR.org.
87:Australian megafauna
538:2020EGUGA..2212314C
480:2021Sci...371..766V
395:. 19 February 2021.
65:cosmogenic isotopes
33:Last Glacial Period
694:Pleistocene events
585:The New York Times
415:. 18 February 2021
140:Radiocarbon dating
343:(6531): 811–818.
288:978-0-444-51928-3
240:(5670): 462–464.
80:atmospheric ozone
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663:. 13 March 2019
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120:, who wrote in
114:science fiction
112:, a tribute to
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25:Laschamps event
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43:in the 1960s.
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157:Solar cycle 1
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665:. Retrieved
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639:. Retrieved
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609:29 September
607:. Retrieved
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507:. Retrieved
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201:(1): 43–46.
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91:Neanderthals
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68:beryllium-10
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667:15 November
641:18 February
628:. Science.
557:11475/21883
447:25 February
419:19 February
294:18 February
152:Solar cycle
106:Adams Event
57:cosmic rays
683:Categories
316:19 October
180:References
136:kauri tree
566:234999027
532:: 12314.
504:231963027
373:231955607
357:0036-8075
254:0028-0836
72:carbon-14
496:33602836
365:33602851
146:See also
130:Research
95:cave art
76:decrease
21:Laschamp
534:Bibcode
509:8 March
476:Bibcode
468:Science
337:Science
203:Bibcode
116:writer
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234:Nature
41:France
27:was a
562:S2CID
500:S2CID
369:S2CID
275:(PDF)
163:Notes
61:Earth
669:2021
643:2021
611:2019
511:2021
492:PMID
449:2021
421:2021
361:PMID
353:ISSN
318:2012
296:2021
283:ISBN
250:ISSN
74:, a
70:and
19:The
661:Eos
552:hdl
542:doi
484:doi
472:371
345:doi
341:371
242:doi
238:274
211:doi
168:1.
108:or
78:in
23:or
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262:^
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