Mystery of The Giant's Causeway in Ireland has been unlocked

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Yay basalt columns! They’re my favorite geology in eastern Washington.


Yep! Same stuff the Devil’s Tower is made of:

Devil’s Tower



The Irish fellow often gets his name transliterated as “Finn MacCool,” which is a pretty good name for an ass kicker.

Etymologically, the “Tuatha de Dannan,” or ‘race of giants’ to which both parties here belonged, shares the same Indo-European root as Teuta/Teuton, and later “Deutsch,” - the ‘tribe’ or ‘people’ reflex word: “Us”…


Also Hughes Mountain in Missouri, though less impressive.


AHA! I was curious as to whether your geologic weirdness (Basalt? In MIssouri?) was anywhere near the New Madrid fault line, and well…it’s not that far away.


in Northern California (went there a couple times as a sprout):


nice to know the story of the place behind the Houses of the Holy cover.


“When the larger giant heard that Fionn had come to Scotland to fight him, but turned coward at the last moment, he set out for Ireland across the causeway to lay a curb stomping on poor Fionn.”

Such is the fate of all Irish mere giants…


It’s rhyolite (not basalt) in Missouri, but it was formed the same way, columnar jointed volcanics.

I don’t know what, if any, connection there is to the New Madrid fault zone. These mountains are volcanic in origin, but they are much older – like 1.5 billion years.


In the small category of “basalt column formations by the seaside,” don’t forget Ganh Da Dia, in Tuy An, Vietnam:


The fault line is the result of a ‘bad weld’ when one of supercontinents broke up and reformed. Because it never did heal right, the scar tissue (to extend the metaphor) isn’t expanding and contracting at the same rate as the rest of the plate/plates. The Mississippi just carved through the path of least resistance.

Let me find a date and a name for the continent, but I’ll bet your rhyolite is about the same age… NOPE! It’s twice as old as the bad weld.

New Madrid Seismic Zone


Yea, right. I don’t think it’s called the “Irish Volcano’s causeway.” I’ll just stick with the giant theory until this crap is peer-reviewed.


You sure it isn’t mashed potato and plasticine?


kinda like the way you want to eat your biscuit …snappy

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So does that mean that they are not formed like crystals at all?
Crystals form from a seed that expands where as these are a field that splits.

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Benandonner destroyed the causeway in his haste to get back to Scotland, hence the state it’s in today!

See also: Fingal’s Cave in Scotland and Svartifoss in Iceland.


Kinda yes and kinda no. [cue the sound of trolls awakening: “Fight? Fight right now?”]

I’ll let someone more ambitious go dig up the Links of Argument, but as the semi-liquid hot rock cools (slowly, v-e-r-y slowly), it does solidify in a regular pattern - hexagonal…BUT, it’s chemical composition isn’t pure enough to form obvious crystals with a lattice structure.

That’s a super-simplification, but I don’t have time right this minute to blow the dust off my Manual of Mineralogy. I hope that’s enough to point you in the right direction for your own search.

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Oooooo! Neat-o!

How far apart are Giant’s causeway and Fingal’s cave?

When things go wrong and will not come right,
Though you do the best you can,
When life looks black as the hour of night -
A pint of plain is your only man.

When money’s tight and hard to get
And your horse has also ran,
When all you have is a heap of debt -
A pint of plain is your only man.

When health is bad and your heart feels strange,
And your face is pale and wan,
When doctors say you need a change,
A pint of plain is your only man.

When food is scarce and your larder bare
And no rashers grease your pan,
When hunger grows as your meals are rare -
A pint of plain is your only man.

In time of trouble and lousey strife,
You have still got a darlint plan
You still can turn to a brighter life -
A pint of plain is your only man.

-Flann O’Brien (Brian O’Nolan)