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Monday, August 29, 2011

The Mountain Cannot Bow To It

I've always been drawn to mountains.  As a kid I lived in western Washington and could see Mt. Rainier in the distance on any clear day.  It was always stunning, and awesome.  As a geologist, I've spent my professional time studying the tectonic and geochemical processes involved when mountains are built up and eroded back down.  Obviously geoscientists have a thing for mountains; they are fantastic and reveal their secrets only after copious amounts of time in the field and lab.

Beyond the scientific interest, however, it seems that mountains have always held an allure to people.  People have found ways to relate them to their lives.  So in this post, I'm taking a step away from the science and even the just fun geoscience related stuff to write something a bit more from a literary, life, and character standpoint.  References to mountains pervade our culture (speaking as an English-speaking white person from a wealthy western nation), and not just ours but also the cultures of many people groups throughout geography and history, space and time.  Mountains are often used as literary references for various principles in life.  Things we love, admire, respect, and fear.  Things we must overcome, or things that might protect us, or perhaps things that might bring terror down upon us.

One of my favorite references to mountains comes from the Disney movie 'Mulan'.  In one critical scene of the story, there's this fantastic 'kneel before zod' movie moment, where the antagonist warrior Shan-Yu orders the Emperor of China, "Bow to me!".  The Emperor holds his cool, and in strength-of-the-man-of-steel fashion calmly replies:  

"No matter how the wind howls, the mountain cannot bow to it."  

I love the emperor's clarity, tenacity, and boldness.  It's one of those story moments where, although he clearly does not possess the physical strength to overcome the snarling warrior, nonetheless he possesses a strength of character that somehow makes up for the gross difference in physical power.  Here, the mountain represents strength, endurance, and steadfastness in the face of the threat.  Life is full of people who howl like some awful bag of wind, crying to us that we bend to their demands.  You see, if you're a tree, you may stand up to the wind, you may not.  You may end up getting blown over when some wind-bag suggests you compromise your ethics so whatever-it-is on the job-site will have an easier go, never-mind the risks or who might get hurt.  But if you're a mountain, well, you simply can't.  

Friday, August 26, 2011

Accretionary Wedge #37: Sexy Geology: Bancroft, Ontario

For the first time in this blog, I've decided to join a host of other geobloggers in the geoblog carnival, which is aptly named The Accretionary Wedge.  This time around, Lockwood at Outside the Interzone has called for posts around the topic "Sexy Geology", described as geology that makes you heart race and your pupils dilate.

In thinking about what to contribute many places came to mind, but in the end so many of them are found near a magical place called Bancroft, Ontario.  Bancroft is a small town that is world renowned for its mineral specimens.  It is the "Mineral Capital of Canada", due to the great allure of the area to rockhounds and mineral collectors, who are drawn there not only for the vast number of minerals that can be found but also the quality of specimens in size and shape.  Of the ~4000 known minerals, at least 1600 are known in the Bancroft area, some sources have said the number is even higher.

There are way too many sites around Bancroft to really give a full account; I'll highlight just a few of my very favorites:

1) Egan Chutes Provincial Park at the York River:
This locality includes several stops on both sides of the York River-
The Goulding-Keane Nepheline Pegamtite Quarry (N 45° 04.201’, W 077° 43.947’) is an abandoned small quarry with easily seen large crystals of magmatic nepheline, biotite, calcite, sodalite, and zircon.  The zircons are large enough to be seen in hand specimen!  This quarry is the source of the large dump of crushed rock in the center of town (N 45° 03.432’, W 077° 51.379’), where rockhounds can pick through these rocks and take what they like.
Continuing down the trail from the G-K quarry, you'll reach the main chute, where the river pinches down at a terrific waterfall (N 45° 04.473’, W 077° 44.081’). The nepheline gneisses here also contain diopside, scapolite, hornblende, plagioclase, and at one point in time contained sapphire (but the larger samples have all been removed).
Egan Chute Falls
Heading back, across the York River from the G-K quarry mentioned above lies the York River Skarn (N 45° 04.210, W 077° 43.914’). The unaltered marble can be seen in a roadcut (N 45° 04.066’, W 077° 43.874’) just before the trail to get to the skarn, which is good to visit before seeing the skarn to truly appreciate the changes that took place in these rocks as the nepheline pegmatite intruded (and it has some spectacular sigma clasts). At the skarn, about 50 minerals have been described at this single outcrop, including garnet, diopside, wollastonite, vesuvianite, forsterite, clinohumite, spinel, clintonite (a green, Ca-mica), among many others.

2) MacDonald Mine:
This is an old uranium mine in a granite pegmatite  (N 45° 09.928', W 077° 49.189'), dominated by GIANT K-feldspar & quartz crystals. Some of the K-spar crystals are ~10' long, and some quartz grains are the size of beach balls. Much of the quartz is dark & smokey, due to the presence of the uranium ore mineral, uranian pyrochlore ("ellsworthite"). The pyrochlore grains themselves are typically round & ~4 inches in diameter. And they are HOT. They will send your Geiger counter into awesome mode. Also present are andradite (black Fe+3-rich garnet), sphene, and zircon. As an American, it is really surprising to be able to freely enter a place like this; in the U.S. this mine would be surrounded by 20' tall fences, barbed wire, and very large guards with very large dogs and guns; the size of the KEEP OUT signs would reach epic proportions. But here in Bancroft, you can just park at N 45° 09.846’, W 077° 49.160’ and hike in.




3) Orange Calcite Roadcut: 
Along Monck Road, a cut at the top of a small hill (N 45° 00.169’, W 078° 00.360’) displays some fascinating rocks with orange calcite and large grains of white tremolite.  Several grains of a highly radioactive mineral I have yet to identify are present here, which are easily found with a Geiger counter as they set it on fire.
orange calcite and large white fibers of tremolite


4) Green Mantle Farm Eco-Tour:
If you have the time, and really, you should make it, there is no substitute for taking a tour with Mark Bramham through his property and adjacent Crown land to see some truly fantastic mineral specimens in the wooded areas surrounding his home (N 45° 00.663', W 078° 14.903').  No sample collecting is allowed, but you won't regret going.  Let me just say "fluororichterite stream".  Richterite is an amphibole like tremolite, but substitute 2 Na+ for Ca+2, and the richterite here contains significant fluorine for the OH- group.  There are very few places in the world where fluororichterite is known, so your choices for viewing it are limited.
Large dark green crystals of fluororichterite
You'll also see gorgeous GIANT euhedral hornblende, orthoclase, green apatite, and museum quality red clinohumite.  The tour lasts 2.5-3 hours, and their playful dogs add to the charm of this wooded walk.  Although he's sitting on a mineralogical gold mine, Mark's passion for conservation is inspiring.  Besides the material found on his own property, He has used the mining law to stake a claim on the adjacent Crown land so that he could protect the minerals and keep them in their natural place for future generations to see.
Euhedral hornblende crystals

Euhedral orthoclase crystals

So there you have it, my take on Sexy Geology, with a virtual visit to Bancroft, Ontario.  And this is but a small slice of what is available in this area!



Friday, August 19, 2011

GeoPic: Diamond Head Crater

I readily admit I'm not a great photographer, but occasionally I get a shot worth sharing. Here's a picture I took of Diamond Head Crater while on vacation in Hawaii.


The shot was taken from an aircraft (obviously); we were on a commercial flight from Honolulu to Hilo. I had a window seat and was looking north. The clouds parted just perfectly for a moment and I was able to get this shot. My wife and I had just climbed Diamond Head a day or two before, but seeing it from the air was really stunning.

Diamond Head crater is interesting geologically because the volcanic eruptions from this crater, and a number of others like it on Oahu, are much younger than the rest of the island. Most people are aware, I hope anyway, that the Hawaiian Islands were formed as the Pacific plate moved across the top of a hot spot. The hot spot is still active today, producing volcanism on the Big Island. Most of the volcanic rocks of Oahu are between 2-4 million years old. Oahu is now over 200 miles from Kilauea, and the age of the island is consistent with the modern tectonic rate of movement of the Pacific plate at around 9 cm/year. But Diamond Head and a number of other volcanic craters are much younger, less than 500 thousand years old. By this point, Oahu was well beyond the hot spot, and most of Oahu had been undergoing erosion for over a million and a half years! So based on all of this, these young volcanic craters on Oahu are very strange - if Oahu was not over the top of the hot spot anymore, why were these volcanoes erupting? This is a point of current research & debate among geoscientists.

Sunday, August 14, 2011

Geo Culture Snapshot I

There's no secret that geologists have some common ways of going about life and our business.  Although the culture of geoscientists is yet to form the basis for any dissertations yet, there are nonetheless millions of pictures out there showing us at our best... and sometimes not so best I suppose...

For instance, we geologists love our geo-T-shirts. Here's one I spotted this last week at the SERC Teaching MPG workshop.

And here's another pic showing geoscientists putting thermodynamics to good use.

Friday, August 5, 2011

GPS to fail with solar flares?

I just read an article on CNN talking about how solar flares might cause problems for GPS users.  I was pretty excited to read the article because GPS technology is something I'm very interested in.

But I guess I have to admit that the article left with with a "wait, what??" feeling.  I didn't get enough information from the article to really understand what was going on, only a vague feeling of "GPS might go kaputz sometime".  It boils down to a general warning that GPS may, or may not, fail for some unknown period of time, sometime in the future... I'm really hoping for more detail - when will these events occur?  How intense will they be, how long will they last, and what capabilities should I expect to lose?  Airlines, rescue squads, surveyors, and websites like geocaching.com could certainly benefit from these details.

Apparently a solar flare recently left the sun - the article gives a couple of links to some videos that are kind of interesting to view - and this flare may cause problems for all kinds of GPS devices.  The reason for this comes from research at Cornell University, where researchers detected a significant loss of signal (40-50%) during a solar flare in 2005.  The signal loss consisted of two events, one that lasted one minute, 10 seconds, and a second 40 minutes later that lasted 15 minutes.  The solar flare affected, apparently, all GPS units on the sunlit side of the Earth.  But even this article isn't clear on the implications of a 50% drop in signal for GPS users.  The CNN article also doesn't give any information about when this latest solar burp might reach Earth.

A loss of signal would certainly cause your GPS device to have a harder time calculating where you are, but what's not clear from these articles is how much of a problem this would be for ordinary GPS users.  Who needs to be concerned, and who doesn't, and when?  At one point, the author says to "have a backup navigation system handy, such as a printed map", which obviously suggests that us normal folks driving around might suddenly not be able to use our GPS units to get where we want to go.  Yet the Cornell Univ. research  quoted from 2006 states that "if you're driving to the beach using your car's navigation system, you'll be OK."  So should folks expect that they will need a map, or should they expect that their car GPS will be just fine?

Obviously it will also depend on the size of the solar flare; another point of the articles is that 2011 and 2012 are years where we expect some long, intense solar flares, due to the solar maximum.  These flares, according to the Cornell Univ. researchers, could be expected to result in a 90% loss of signal that could last for a couple of hours.  Now that sounds pretty serious and an event like that deserves some further investigation.  If that kind of signal loss is really to be expected, then specific warnings for certain time periods when such flares are expected to strike Earth are needed - now who's in charge of that one?  People rely on GPS a lot these days, for good reason - it's amazing tech!  I would hope for specific warnings when such signal loss should be reasonably expected; a generic one is somewhat useful but not as empowering to users.

Thursday, August 4, 2011

Earth's lost 2nd moon?

Yesterday, news suggesting that the Earth once had a second, smaller moon, erupted onto the interwebs. The model is based on the fact that the moon has two sides - a dark, basalt covered side that faces Earth, and a lighter, more mountainous side made of anorthosite. How the moon obtained its dual sides is unknown, and a number of hypotheses have been put forth. This latest model is the result of computer simulations of the moon's formation.

Based on available data, it is very likely that the moon originated when a Mars-sized body collided with Earth. This collision would have happened very early on in Earth's history; it can be thought of as the final major coalescence of planetesimals that built up the Earth. During that collision, which is sometimes referred to as the Big Whack, the moon would have formed from the debris ejected out into space. Some models of this collision result in additional, smaller satellites forming along with the moon. If a second, smaller moon were to have formed, it would have only been gravitationally stable for a short period of time, geologically speaking. If it were to have slowly collided with the moon, that collision could potentially explain why the moon has its two different sides.  It will be interesting to see how this hypothesis stands up to testing in the coming years.

And now to a related question:  how would two moons have affected Archean Werewolves?

Wednesday, August 3, 2011

wikiproject geology

I feel a bit responsible to join the WikiProject Geology, but so far I've stopped short of taking the plunge. It means setting up another account on another website and trying, somehow, to find some time to make some meaningful contributions. It's that latter part that has held me back - time. However, I've love to hear from someone who contributes to it - the process, the contributors, the needs, etc.

good times...

"and suddenly it was as clear as a walk on the beach... they were ripple marks... GIANT ripple marks."