De nouveaux indices révèlent un rift tectonique émergent en Zambie

12 mai 2026

Rapporté par l'IA

Des gaz provenant de sources thermales dans le centre de la Zambie révèlent des signes de fluides mantelliques remontant à la surface, suggérant le stade précoce d'un rift continental. Les chercheurs estiment que cela pourrait marquer le début d'une nouvelle frontière de plaque tectonique. Ces découvertes proviennent d'échantillons collectés dans le rift de Kafue.

Le rift de Kafue fait partie d'une zone de 2500 kilomètres s'étendant de la Tanzanie à la Namibie. Les géologues ont longtemps noté sa faible gravité, sa forte chaleur souterraine et ses séismes mineurs, mais manquaient jusqu'à présent de preuves directes d'une activité profonde. L'analyse des isotopes d'hélium et de carbone provenant de cinq sources thermales et de trois puits correspond aux signatures issues de profondeurs allant jusqu'à 190 kilomètres sous la croûte terrestre.

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