The Dolerite Columns of Coastal Tasmania

The coastline of the southern Tasmania, in Australia, is composed of stunning rock columns that protrude up to 300 meters from the sea level.

These rocks are what geologists call dolerites, with its distinct elongated shape and hexagonal columns.

Dolerites form when molten rocks pushed up from the deep underbelly of the earth cools quickly and crystallizes to form small visible crystals in the rock.

When the rate of cooling is just right, the rocks shrink in volume, causing the creation of cracks.

The cracks allow the rocks in the interior to cool, resulting in more cracks.

At the end, you get a large block of rock with long vertical and symmetrical cracks creating five or six sided columns.

The columns can be just a few centimeters to over several meters in diameter.

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