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Earth of fire

Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage

Fogo Island has other volcanic landscapes than caldera and Pico do Fogo .

On the north coast of the island, the black sand beach of Ponta das Salinas is one of the most beautiful . A succession of creeks bordering basalt cliffs sculpted by wind and sea erosion. It dug a bridge in a basalt flow .
The place is popular for fishermen who shelter their boats. Protected from currents, Ponta das Salinas also has a natural pool where swimming is safe.
A cemetery is perched on the cliff overlooking the surf.

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  Fogo - Ponta das Salinas , creeks lined with basalt cliffs - photo © Carole and Frederic Hardy 2013.

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Photo © Carole and Frederic Hardy 2013.

Fogo - Ponta das Salinas, an arch that gave its name to the place - photo © Carole and Frederic Hardy 2013.

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            Fogo - basalt cliff with prismation - photo © Carole and Frederic Hardy 2013.

Sao Vicente has vertical dykes with a
characteristic horizontal prismation.

After complete solidification , the lava flow continues to cool . This results in thermal shrinkage,  a reduction in volume and the genesis of fracture. These fractures start with the edges of the mass of lava to progress towards his heart .
The prisms formed end up perpendicular to the top and the base of the flow, with the possibility of heterogeneity .

In dykes against, by the cooling rate identical on both sides of the vein makes the prismation
homogeneous with formation of continuous prisms through the dyke.

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              Sao Vicente - basaltic dyke and prismation - photo © Carole and Frederic Hardy 2013.


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