GEOLOGY 101 Columnar Basalt
Rock&Gem Magazine|December 2020
A distinctive volcanic structure found throughout the world has been given fanciful names: “Organ Pipes” in Namibia and Victoria, Australia; “Kilt Rock” and “Samson’s Ribs” in Scotland; “Giant’s Causeway” in Northern Ireland; “Thunderstruck Rocks” in Romania; “Devils Tower” in Wyoming and “Paul Bunyan’s Woodpile” in Utah, USA; the “Baigong Pipes” in China; and the “Cliff of Stone Plates” in Vietnam. High-resolution satellite images have even shown similar as-yet-unnamed structures on Mars.
Jim Brace-Thompson

What is the distinctive structure all these have in common? They often are composed of basaltic lava flows that cooled to form “columnar basalt.” Columnar basalt exhibits massive, vertically standing columns. Although usually hexagonal (six-sided), such columns are polygonal (multi-sided) and may have anywhere from three to 12 sides. They are often so uniform in size and shape that they seem to have been artificially constructed, like giant columns of poured concrete. But these columns most definitely were not crafted by the hands of humans!

Rather, they are natural formations resulting from the cooling of thick outpourings of lava. Under certain conditions, lava contracts as it cools.

Continue reading your story on the app

Continue reading your story in the magazine

MORE STORIES FROM ROCK&GEM MAGAZINEView All

ROOSEVELT DAM AGATE: A Gem Loaded with History

The Roosevelt Dam agate is a very limited-occurrence lapidary material, uncovered during the excavation of the Theodore Roosevelt Dam in Arizona, hence the obvious name of Roosevelt Dam agate.

4 mins read
Rock&Gem Magazine
February 2021

GEORGIUS AGRICOLA'S: DE RE METALLICA

465 Years Old and Still Relevant

10+ mins read
Rock&Gem Magazine
February 2021

Trisparkle 12 Design Marks New Approach

I want to thank Jim Perkins for his many years of providing outstanding faceting designs for the Rock & Gem readership.

2 mins read
Rock&Gem Magazine
February 2021

Scientists Looking at a Possibly Undetected Volcano in Alaska

Is there a previously undiscovered volcano within Alaska’s Aleutian chain of islands? A team of scientists recently presented their findings surrounding this possibility during a meeting of the American Geophysical Union (AGU).

3 mins read
Rock&Gem Magazine
February 2021

QUARTZ

COMMON, BUT NOT CONVENTIONAL

8 mins read
Rock&Gem Magazine
February 2021

Discovering the Splendor of SLAG

A pile of slag remaining from copper smelting operations of 1930s Cottonwood, Arizona is one area of focus for Minerals Research, Inc. (MRI), the company pursuing a 15-20 year process to remove the pile using innovative recovery technology.

10 mins read
Rock&Gem Magazine
February 2021

HUNTING FOR THUNDEREGGS

Uncovering A “Ghost” Volcano’s Treasures

7 mins read
Rock&Gem Magazine
February 2021

CERUSSITE

GALENA’S GIFT OF A STUNNING SECONDARY MINERAL

7 mins read
Rock&Gem Magazine
February 2021

Anxiously Awaiting a New Museum Opening

With the year 2021 upon us, Arizona collectors are certainly excited about the pending May opening of the University of Arizona Alfie Norville Gem & Mineral Museum in downtown Tucson. Of course, the excitement extends beyond the border of Arizona and to far reaching locales around the globe.

7 mins read
Rock&Gem Magazine
February 2021

Captivated By Copper

Soldiers’ Discovery Leads to a Century of Mining at Pearl Handle Open Pit

7 mins read
Rock&Gem Magazine
February 2021
RELATED STORIES

SCOTTISH SOUNDINGS

A SPONTANEOUS CRUISE ALONG SCOTLAND’S WILD WEST COAST PROVED TO BE A VOYAGE OF SURPRISES FOR PHIL JOHNSON

10+ mins read
Yachting World
April 2021

A Wee Dram

There’s more to love about Scotland’s favorite libation once you discover the magic

6 mins read
Business Traveler
April/May 2021

Alexandra Sipa

Through the Wire

10 mins read
JUXTAPOZ
Spring 2021

Taking Scotland in Stride

A walk through the Highlands and Borders is the best way to touch this country’s history and nature

5 mins read
Business Traveler
December 2020/January 2021

Scotland Makes Periods Less Painful

The country is the first in the world to offer free, universal access to sanitary products

2 mins read
Bloomberg Businessweek
December 07, 2020

A REACH TOO FAR

This is not the story I thought I’d be writing when I began my motorcycling adventure on Namibia’s gravel roads.

8 mins read
Adventure Motorcycle (ADVMoto)
November - December 2020

AFRICAN DREAMS

With cruises that visit South Africa, Botswana, Namibia, and Zimbabwe, CroisiEurope shows off the best that land and water have to offer.

5 mins read
Porthole Cruise Magazine
September/October 2020

Can An Unlove Child Learn to Love?

Thirty years ago, the world discovered tens of thousands of children warehoused in Romanian orphanages, deprived of human contact and affection. They’re adults now.

10+ mins read
The Atlantic
July - August 2020

Bass of Tomorrow

We can think of a few string manufacturers who claim to make the best-sounding products in the world. Dr Jonathan Kemp doesn’t just make that claim—he can prove it, too. Hywel Davies is blinded with science...

2 mins read
Bass Player
July 2020

ESCAPIST UTOPIA

A JOURNEY FROM THE HEART OF NAMIBIA TO THE SKELETON COAST IN LAND ROVER’S STUNNING NEW OFF-ROAD CHAMPION

9 mins read
Motor Trend
June 2020