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Coupled paleomagnetic/dating investigation of the Upper Jaramillo reversal from lava sequences (Tenerife, Canary islands)

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Coupled paleomagnetic/dating investigation of the Upper Jaramillo reversal from lava sequences (Tenerife, Canary islands)

Author: Laj, C.,Kissel, C.,Guillou ,Hervé,Carracedo, J.C.,Perez-Torrado, Francisco-Jose,Rodriguez-Gonzalez, Alejandro,Wandres, Camille,Nomade, Sebastien
Year: 2013
Source: https://accedacris.ulpgc.es/jspui/bitstream/10553/10361/4/0683383_00000_0000.pdf
Geophysical Resea ch Abs ac s
Vol. 15, EGU2013-9259, 2013
EGU Gene al Assembly 2013
© Au ho (s) 2013. CC A ibu ion 3.0 License.
Coupled paleomagne ic/da ing in es iga ion o he Uppe Ja amillo
e e sal om la a sequences (Tene i e, Cana y islands)
Ca lo Laj (1), Ca he ine Kissel (1), He e Guillou (1), Juan-Ca los Ca acedo (2), F ancisco Pe ez-To ado (2),
Alejand o Rod iguez-Gonzalez (2), Camille Wand es (1), and Sebas ien Nomade (1)
(1) Labo a oi e des Sciences du Clima e de l’En i onnemen , CEA-CNRS-UVSQ, Gi -su -Y e e Cedex, F ance
([email p o ec ed], 33 1 6982 35 68), (2) Uni e sidad de Las Palmas de G an Cana ia, Spain
A sequence o la a lows has been emplaced du ing he ansi ion be ween he Ja amillo subch on and he
Ma uyama ch on in Tene i e (Cana y island). This sequence is loca ed along he lank o he collapse o Güima ,
in he sou h cen al pa o he island. I includes 26 lows om he ull no mal pola i y o he ull e e se pola i y.
On he basis o K/A da ing, he sec ion is b acke ed be ween 1012 ±18 ka and 975 ±17 ka. Addi ional coupled
K/A and 40A /39A da ing ha e been ob ained h ough he sequence and place he e e sal i sel be ween 992
±12 ka and 979 ±10 ka consis en ly wi h p e ious da ing o he uppe Ja amillo e e sal. They indica e a
pa icula ly high ex usion a e a his si e (Guillou e al., session IG9/GMPV7/PS9.6).
Full paleomagne ic analyses ha e been conduc ed on hese la a lows including ock magne ic analyses ( he mo-
magne ic cu es, hys e esis cu es, FORC diag ams, k-T cu es), ze o- ield s epwise he mal and al e na ing ield
demagne iza ions. Thellie and Thellie paleoin ensi y (PI) de e mina ions we e also pe o med and based on he
selec ion c i e ia de ined by Kissel and Laj (2004), only 30% o he samples yielded eliable esul s.
The i s 9 lows a he bo om o he sequence a e cha ac e ized by a no mal pola i y. Only wo o hem yield PI
consis en wi h he p esen day ield in ensi y in he Cana y islands. The wo ollowing lows a e de ia ed om he
magne ic pole, beyond he secula a ia ion bu hei VGP is s ill in he no he n hemisphe e, o e no heas e n
Paci ic. The associa ed in ensi y d ops signi ican ly o abou 11 µT ha is less han 30% o he p esen dipole
alue. The ollowing lows ha e all a nega i e inclina ion and hei PI emain low (a ound 8-12 µT). The i ual
geomagne ic poles a e i s o e Eas An a c ica be o e desc ibing a no hwa d loop almos up o New Zealand.
The VGPs hen go back close o he sou he n pole, and ma k a second loop o sou heas e n Paci ic associa ed wi h
li le g ea e PI (19- 23 µT). Finally, he las eliable PI da a is a ound 25 µT, sligh ly close o he p esen day
in ensi y alue. Al hough i is delica e o econs uc he exac e up ion a e, he d op in paleoin ensi y p io o he
majo di ec ional e e sal appea s o occu mo e apidly han he slow eco e y. When conside ing he PGV pa h,
we lack in e media e poin s o desc ibe i ully bu he ansi ional poin s we ha e a e consis en wi h he de ailed
pa h epo ed o his e e sal om sedimen s.