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Far-Away Iceland

ICELAND

-----Great rifts in society create massive shifts in human history. The same is true for planet Earth - rifts cause shifts. Rifting in Iceland creates many of America's mountains, earthquakes, and much of the scenery around you.

-----Beneath your feet, is a cauldron of churning heat. You are, as you read this, only a few miles from temperatures so high that the very rocks are molten.

----The solid rock on which we live is an illusion. In truth, it is merely a thin skim, like fresh ice crusting a lake. Below our crust, huge upwellings of red-hot rock mound upward, cracking and rifting the crust. Our world is forever changed by restless subterranean whims.

----For us in North America, far-away Iceland is where it happens. Our mountains, river courses, and earthquakes are birthed by events in Iceland.

GEOLOGY

BORN FROM FIRE

-----Perhaps the best way to understand Earth's interior, is to first consider what we know -- the thin crust on which we live. We survive on this small ball, rotating through the frigid world of space, because of warm rays from our sun. But, because we live on a ball, this heat is not evenly distributed over Earth's surface. Incoming sunlight is directly overhead in equatorial regions. This concentrates the solar heat. Polar regions, with a low incidence angle of the solar rays, are correspondingly much colder. In an attempt to equalize this imbalance, huge convection cells in the atmosphere churn hot air from the equator toward the poles. Wind is the result. The windy cells are relatively fixed in their patterns and give rise to climate zones on Earth's surface. We know what clothes to bring on a trip to Hawaii and they would be distinctly different from those we wore on that Alaska cruise.

-----Winds, however, are lightweights when it comes to doing the heavy work of transferring the solar inequities of heat. Air can quickly be heated or cooled, especially if it is dry. I turned up the heat this morning after a cold winter night, and within a few minutes the air was warm and cozy.

-----Now, if I had done that with a swimming pool, it would have taken hours or days to raise the water temperature the same amount. Water can carry far more heat and retain it much longer than air. About seventy percent of the earth's surface is water. Consequently, most of the inequality in heat distribution on Earth's surface is resolved through ocean currents - great convection cells of warm water moving toward the poles with equally great cells of cold water (often traveling along the bottom of the oceans) toward the Equator.

-----Now this gets us to the earth's interior. Convection is the necessary element toward equilibrium, whether wind or ocean currents on Earth's surface or massive flowing magmas in the subsurface. Directly beneath you as you read this, molten rock is 'churning' (in a geologic sense) in great convection motion. For most of us in North America, the flow is pushing us westerly. This force is like a conveyor belt beneath our continent, pushing us all to the west about as fast as your finger nail is growing.

-----The force propelling us is located far-away in the middle of the Atlantic Ocean. There a great convective upwelling, along the axis of the ocean, that is shoving the crust, west of Iceland, to the west and the crust, to the east of the island, to the east -- geologists call this a spreading center.

The Bridge Between the Continents - left is North America; right is Europe

-----To compound the problem of sitting astride a spreading center, Iceland is also above a Hot Spot -- an especially concentrated flow of heat welling up below Iceland. The surface crust of Iceland is literally ripped apart and huge eruptive volcanoes crown the island.

----The rock of Iceland is virtually all lava, except where some oceanic sediments have covered the lavas around the island periphery. So Iceland is directly astride a Hot Spot that itself is directly above the Mid-Atlantic Spreading Center.

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On the Hot Spot

-----It is blasted by numerous volcanic eruptions and lava flows. Many of the farms and homes of the Viking settlers have been buried by lava flows and volcanic ash, and eruptions continue today.-In 1783, Laki volcano erupted over the hot spot and 9,000 people died, mostly through famine resulting from crop failure due to outpourings of sulfur dioxide. It spewed lava over 200 square miles - enough to bury Manhattan more than halfway up the Empire State Building. It created one of Europe's coldest winters recorded. The oldest rocks found in Iceland are only 16 million years old - making Iceland a geologic child -- a child of fire.

------In summary, Iceland sits atop both a Spreading Center and a Hot Spot. This is a place of new rock and new crust -- a place of huge volcanos and lava flows. The island is rifted almost up the middle, with the western portion the newest part of North America and the eastern side of the Rift the newest crust of Europe. It is surely a hot place to observe geology.

SHAPED BY ICE

Fire and Ice

Some say the world will end in fire,

Some say in ice.

From what I've tasted of desire

I hold with those who favor fire.

But if it had to perish twice,

I think I know enough of hate

To say that for destruction ice

Is also great

And would suffice.

--Robert Frost

...Some Say in Ice

-----The child of fire was recently buried under glacial ice during Ice Age. A third still is. And, as Robert Frost states, "for destruction ice is also great."

White Patches are Glaciers, Pink Band is the Rift Zone

----Glacial advances, during the cooling period of the eighteenth and nineteenth centuries, buried Viking farms but the most serious threat to humans in Iceland was and is a rather unique combination of fire and ice -- jökulhlaup!

-----Imagine a volcano erupting beneath a glacier! Wow! Red-hot gases, molten lava, explosive eruptions - under a half mile of ice! Now that's something that perhaps even Robert Frost did not consider when he was pondering the destruction by fire or ice - a combination of both! Of course, this is not something ever witnessed by a human, but your imagination can conjure up the ghastly scene.

-----Humans have, however, witnessed the horrific result -- a jökulhlaup -- a horrendous flood of meltwater, mixed with volcanic ashes turned to mud, and huge rocks carried in the turgid outflowing mass. These humungous floods occur about every five years along Iceland's south coast and have obliterated all human structures in their paths and annihilated lives since the earliest years of settlement. Vast plains of grey-black sand, rocks, and rushing glacial outwash the color of discarded dish water are lashed by strong winds. Sandstorms periodically close the south coast highway for days and jökulhlaups shred the highway and its bridges forcing closures that may last for years, isolating communities.

The Flood Zone of the 5 Nov. 1996 Jökulhlaup; Aerial View with Ruptured Highway for Scale); And Today's View

A QUICK TRIP AROUND ICELAND - THE RING ROAD

-----Iceland is a wondrous scenic country, seldom visited by Americans. The major port of entry is Reykjavik, a bustling modern town on the west coast of the country. There is a good road, Route 1 or the Ring Road, that was completed in 1974 (it is occasionally closed due to sand storms, ash falls, or jökulhlaups). The 1339 km (mostly) paved road circles the island and is a great driving trip of a week or two. It is a busy highway near Reykjavik but the more remote stretches have fewer than 100 vehicles per day. The most common hazards are some blind bends and blind hills, all well marked.
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Hazards of the Ring Road

YOUTH HOSTELS

-----We think the best places to stay in Iceland are the Youth Hostels. They are comfortable, less expensive than hotels, and you meet interesting people. You can also cook your own meals in most.