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Geology Photo of the Week #8 – Oct 14-20 – Guessing Game!

This weeks photo is a giant bone! I leave it to you to surmise which creature it belongs to….I hope you accept the challenge. Please post your guesses in the comment section below. If no one gets it within the first few hours I’ll start posting hints about the creature. You can click on the photo to enlarge it. Have fun!

Hint 1: This bone was discovered in the Yukon Territory and is housed at the Yukon Archaeological and Palaeontological Survey, which is where I took the photo. Their facility houses all of the bones found in the Yukon as well as all of the archaeological artefacts.

Well, the mystery has been solved.  Congrats to everyone who provided the answer on Twitter as well.

The answer that you have all been waiting for is Wooly Mammoth (Mammuthus primigenius). Yep, this is a bone from a mammoth and it is all of a metre long!! Absolutely massive!

Here are some other pictures of mammoth remains that I snagged from the collection and the local museum.

A complete and gorgeous mammoth skeleton at the Beringia Centre in Whitehorse.

A tusk at the survey.

A newly discovered tusk that just arrived at the survey and had yet to be catalogued.

 Cheers,

Matt

Robert Service – A geologist’s poet

There are strange things done in the midnight sun

By the men who moil for gold;

The Arctic trails have their secret tales

That would make your blood run cold;

The Northern Lights have seen queer sights,

But the queerest they ever did see

Was that night on the marge of Lake Lebarge

I cremated Sam McGee.

My submission for the Accretionary Wedge #51, which I am also hosting, is about my favourite poet of all time: Robert Service. Robert Service was born on January 16, 1874 in Preston, England. He immigrated to Canada at the age of 21 and after working odd jobs for a while throughout British Columbia and California he landed a job as a banker with the Canadian Bank of Commerce who, in 1904, sent Service to their Whitehorse branch. Although already a published poet, it was in Whitehorse that he established himself as one of the premier poets of his day. It was from this point on that Robert Service became the voice of the Klondike Gold Rush and hereafter known as the “Bard of the Yukon”. In 1908 he relocated to Dawson City, which was the heart of the gold rush and still booming even though most of the claiming had been done earlier in the decade. Indeed, in 1908 Dawson claims produced 174,000 ounces of gold (they still produce around 50,000 ounces/year).

The Bank of British North America and the infamous Downtown Hotel (lots of fun to be had in there!) in Dawson City. (Photo: Matt Herod)

Robert Service lived in Dawson until 1912, writing poetry full time in his cabin, which is preserved by Parks Canada as a historic site…like the rest of Dawson. He then moved to Europe during the war years and passed away in 1958.

Robert Service’s cabin (Photo: Matt Herod)

The ballads and poems of Robert Service are my all time favourites. As someone who has been to the Yukon several times they resonate quite strongly for this reason alone. However, even before I was lucky enough to travel there I still loved them. They speak to me on several levels. Firstly, as a fan of Canadian history they invoke the feeling of the gold rush, an important time in Canada, far more effectively than any story or non-fiction ever has. They also speak to me as a geologist. These days gold rushes are more like staking wars between junior mining companies than individual races by men from across Canada and the world to a far flung and wild place. They certainly do not bear any resemblance to the old methods of prospecting, staking or mining gold and poems such as these bring those old days back to life. As modern geologists it would not do to forget our heritage. Today we use sophisticated geochemical and geophysical methods to find gold and it is easy to forget about the blood, sweat and tears of the early Klondikers and the only way to appreciate what we take for granted today is to learn about what the old methods were. The poems of Robert Service bring those days to life in my mind and enhance my appreciation for the evolution of gold prospecting and mining throughout the past 100 years.

For this wedge I also encouraged people to write their own poetry and so I figured that as the host I had better put my money where my mouth is. I am taking a course in glacial sedimentology this semester and TA’ing Quaternary geology so I have glaciers on the brain a little bit right now, which is not altogether a bad thing. I hope you enjoy my poem.

Beautiful flowing stream of ice;

blue, grey, brown and white;

squeezing the land in a powerful vice;

with enormous might;

blanketing the nations in a cold embrace;

creeping forward, toward your toe;

scraping the land at your base;

shaping it like a colossal fresco

receding, advancing, apparently still

yet always in motion, inexorably flowing

Striations, rat-tails, whale-backs, till

Eroding, depositing, always sculpting

Recording chemistry for untold millenia

helium, carbon, oxygen, hydrogen

revealing past climate data

cracking, calving into the salty ocean

Glacier, you are a mighty power

Coming and going throughout Earth’s past

flowing like a mountainous white tower

when is the next ice age forecast?

If you want to listen to some real poetry now that you’ve read mine I recommend the recital of The Cremation of Sam Magee below by the amazing Johnny Cash. I was pretty stoked to find a recital of this great poem by such a fantastic musician as well. It is kind of an awesome double although he does say “toil” instead of “moil”, but it is a minor mistake and doesn’t really matter.

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Thanks for reading and remember, the deadline for AW#51 is coming up on November 1 so get your submissions in!!

Matt

Geology Photo of the Week #7 – Oct 7-13

Sorry this post is a bit late…the Thanksgiving holiday was Monday, class this morning and then hockey! Anyway,  for the 7th edition of Photo of the Week we travel to the Pancake Rocks, in Punakaiki on the west coast of New Zealand’s South Island. I was there in 2011 for a conference in Wellington and went travelling around afterwards.  One of my stops was here. The Pancake Rocks are made of 30 million year old limestone that is very finely laminated. The daily pounding of the surf has led to the amazing convoluted structures in the picture. As to the formation of the Pancake Rocks themselves I cannot find a definitive answer…some sources claim that they are interbedded lime mud and coarser material. Others state that they contain stylolites. Unfortunately, I don’t remember from my own visit which is the case…although I feel like I would remember if it were stylolites so I am inclined to believe the bedding view. Plus the beds seem too regularly spaced for stylolites.  Does anyone else have a definitive answer?

Thanks for reading and let me know which hypothesis you support for the formation of the bedding.

Cheers,

Matt

The Wooden Wall

It is once again time to write about geology and classics and the incredibly important impact the geosciences had on the ancients and their way of life. My previous post on this topic can be found at my old blog location as the post: The Odyssey and Geology. I’ll begin by relating a story:

File:Themistokles.jpg

Themistocles (Wikimedia Commons)


The two fleets, the Persians the the Greeks, which was composed of the navies of all the city states, but mainly Athens, met in the narrow Strait of Salamis for a final and deciding battle. The Persian king, Xerxes, was so certain of victory that he set up a throne in nearby Athens to watch the battle. The true architect of the battle though was not Xerxes, but the Athenian Themistocles, a politician and general. Indeed, it had been Themistocles who had convinced the Athenians to build a navy of over 200 additional ships in the years prior to the war and it was he who stationed the Greek navy in the Strait of Salamis, which was advantageous for the smaller Greek navy. The battle proceeded according to Themistocles’ plan and the Greeks were able to out-maneuver the Persians in the narrow strait and succeeded in decimating the Persian navy. This was a great blow to Xerxes who fled back to Persia with much of his army. The next year the Greeks were able to defeat the remainder of the Persian army driving them out of Greece and winning the war. Salamis was the turning point of the war and saved Greece from certain doom.In 480 BC the ancient Greeks were faced with their biggest threat in history: the invasion of the Persian king, Xerxes and his armies. The Greeks, despite being horribly outnumbered had fought bravely but been defeated in the Battle of Thermopylae. The Persians then advanced through Greece nearly unchecked and conquered Athens.  However, the Persians knew that to fully conquer Greece they would have to do so at sea as well as on land. Things were looking pretty grim for the future of ancient Greece at this point.

File:Battle of salamis.png
Source: Wikimedia Commons

The hero of Salamis, Themistocles was a very persuasive politician as well as tactician. In fact, it was he who convinced the Athenians to build the 200 triremes (ships) that made of up the bulk of the Greek navy and can be credited with saving Greece. The credit cannot be only given to Themistocles though. In fact, the idea came from the Oracle of Delphi. The Greeks were very worried about the impending Persian invasion and decided to consult the oracle for advice on how to win the war. The oracle cryptically answered along the lines of the “wooden wall will save you”. Clearly, this answer could not refer to the building of an actual wooden wall since that would be stupid and obviously could burn down. Themistocles interpreted the oracles advice to mean build a navy. Unfortunately, the ancient Greeks had the same problem with national defence requisitions as governments do today and money for such a venture was not easily at hand. However, geology was going to come to the Greeks rescue in the form of a major silver discovery at Laurium, a small mining community just south of Athens, providing the Athenians with enough money to afford a new navy. Without the discovery at Laurium it is possible the navy would never have been built and ancient Greece would have fallen into Xerxes hands. Ergo, geology saved ancient Greece from total domination by the Persian empire.

So now what about Laurium?

File:Mineurs grecs 2.jpg
Miners in Laurium. They were all slaves. (Source: Wikimedia Commons)
Google Maps

The Laurium silver mines are located just south of Athens and are world renowned for the excellent mineral samples the area still produces in addition to its storied past. The mineralization is of lead, zinc and silver and is associated with the emplacement of an igneous body within metamorphosed sediments. The ore occurs mainly within marble especially at the contact with other metamorphic or igneous rocks (www.mindat.org). The list of minerals found in the Laurium mining district is a mile long and it is actually the type locality for about a dozen minerals as well, making it a world class mineralogical site. The mineral Laurionite is named in honour of the location. In addition to the minerals occurring in the mines there are a host of others that occur in the ancient slag piles left by the Greeks. The slag has reacted with the sea water used in processing the ore in ancient times to produce a suite of new and unusual minerals there as well.

Agardite, Laurium, Greece (Source: www.mineral-forum.net – Used with permission)

 

Diaboleite, Laurium, Greece (Source: www.mineral-forum.net – Used with permission)

 

Conichalite, Laurium, Greece (Source: www.mineral-forum.net – Used with permission)
Nealite, Laurium, Greece (Source: www.mineral-forum.net – Used with permission)

 

Annabergite. Larrium, Greece. (Source: www.mineral-forum.net – Used with permission)

The ancient ore processing techniques of the Greeks were obviously primitive relative to today’s, however, they were still able to extract both lead and silver from the ore. The process essentially involved numerous washes with water in a sloped basin. The heaviest material was collected and smelted, and the resulting slag was carted away and dumped. Since then the slag has had a few thousand years to oxidize and this process has resulted in the growth of all sorts of interesting minerals like the ones pictured above. Laurium is still geologically relevant today from the perspective of the mineralogist or mineral collector as the area still produces some world class specimens.

It has always amazed me how deeply geology is integrated with our lives today, what with our dependence on natural resources for nearly everything. However, it would appear that this is not a new phenomenon and that geology always has been and will always be a crucial part of our lives.

Thanks for reading!

Matt