Géochimie de l'île de la Martinique aux Petites Antilles

HAL Id: tel-00467762

https://tel.archives-ouvertes.fr/tel-00467762

Submitted on 28 Mar 2010

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Shasa Labanieh

To cite this version:

Shasa Labanieh. Géochimie de l’île de la Martinique aux Petites Antilles. Géochimie. Université Joseph-Fourier - Grenoble I, 2009. Français. �tel-00467762�

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Figure I.3: Structure et subduction de la croûte océanique atlantique sous le plateau océanique

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Figure I.4 : Carte bathymétrique de la région Est Caraïbe et localisation des sites de forages 543 et

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K2O (wt%) K2O (wt%)

K2O (wt%)

Figure I.9: Diagrammes K₂O en fonction de SiO₂ de toutes les îles des Petites Antilles, du nord au sud. Compilation de données d’après le site http://georoc.mpch-mainz.gwdg.de/georoc/ au mois de

Juin 2007.

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30 40 50 60 70 80

Saint Martin SabaSaint Eustatius Saint Kitts Redonda Montserrat

0 5 10 15 20 25 30

30 40 50 60 70 80

Guadeloupe Dominique

0 5 10 15 20 25 30

30 40 50 60 70 80

Martinique Sainte Lucie Saint Vincent

0 5 10 15 20 25 30

30 40 50 60 70 80

Les Grenadines Grenade

SiO2 (Wt%) SiO2 (Wt%)

SiO2 (Wt%) SiO2 (Wt%)

Al2O3 (wt%) Al2O3 (wt%)

Al2O3 (wt%) Al2O3 (wt%)

Figure I.10: Diagrammes Al₂O₃ en fonction de SiO₂ de toutes les îles des Petites Antilles, du nord au sud. Compilation de données d’après le site http://georoc.mpch-mainz.gwdg.de/georoc/ au mois de

Juin 2007.

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15.3 15.4 15.5 15.6 15.7 15.8 15.9 16.0

17.5 18.0 18.5 19.0 19.5 20.0 20.5

NHRL

206

Pb/

Pb

207

Pb /

Pb

Petites Antilles Tonga

Kermadec Sonde Aleoutienne Izu - Bonin Luzon

Figure I.11: Diagramme ²⁰⁷Pb/²⁰⁴Pb en fonction de ²⁰⁶Pb/²⁰⁴Pb des laves des Petites Antilles et des

autres arcs intra océaniques. Les données sont celles compilées sur le site http://georoc.mpch- mainz.gwdg.de/georoc/ en juin 2007. NHRL (Northern Hemisphere Reference Line) est d’après Hart

(1984).

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11 12 13 14 15 16 17 18 19

0.703 0.705 0.707 0.709 0.711

87Sr/⁸⁶Sr

0.5115 0.5120 0.5125 0.5130 0.5135 143Nd/¹⁴⁴Nd

Latitude

St Martin SabaSt Eustatius

St Kitts Redonda Montserrat Guadeloupe

Dominique Martinique Ste Lucie St Vincent Les Grenadines

Grenade 12

13 14 15 16 17 18

Figure I.12: Compositions isotopiques du Sr et du Nd en fonction de la latitude. Les données sur les

Petites Antilles sont celles compilées dans le site Georoc en juin 2007.