Wednesday, August 31, 2011

Unforgiving Circumstances

Yellowstone is such a fascinating place. There are over 10,000 thermal features in the park, the highest concentration of geysers, hot springs, mud pots, and fumaroles on the planet. There are believed to be nearly 500 geysers here, more than half the total number of the entire world. North America’s largest extant land mammal, the bison, is found wild here along with the pronghorn, North America’s fastest land mammal. Gray wolves, grizzly and black bears, elk, moose, bighorn sheep, wolverine, red fox, river otter, beaver, and many other diverse wildlife inhabit this wilderness corner of the Rocky Mountains. The Greater Yellowstone Ecosystem is one of the last largely intact northern temperate ecosystems on the planet. It is indeed a fascinating place and I am extremely fortunate to be able to work here for the summer.
However, Yellowstone can also be a most unforgiving place, especially for the incautious visitor. For backcountry hikers venturing away from the popular geyser trails, one decision may well set into motion a sequence of events ultimately leading to some circumstance from which there is no turning back. Sadly, two hikers during this summer of 2011 made their own separate fatal decisions somewhere along the line and paid for it with their lives.
Park officials warn hikers to travel in groups of three or more, make lots of noise when hiking, always be aware of their surroundings, carry bear pepper spray and know how and when to use it. One hundred yards is given as the “safe” distance to keep from bears and wolves, twenty–five yards from everything else such as elk, moose, and bison. It is unwise and illegal to approach any wild animal – the risk is real that you would be considered a threat by them, something to be charged or mauled. This advice is plastered all over the park on signs and in the park newspaper, and rangers remind visitors of it every day. These are park rules, put forth to encourage visitor safety. In the end, though, we make our own decisions whether or not to adhere to the rules. In a place such as Yellowstone there are no guarantees of our safety if we find ourselves following too closely to a grizzly sow and her cub, or if we choose to hike alone into the backcountry.
At the end of the day, responsibility for our fate is ours alone. We will probably never know exactly what happened during the events that led to the deaths of the two hikers, but a lesson can nevertheless still be learned. 
Please be safe out there.

Thursday, August 25, 2011

In Search Of The Elusive Melk – Beginnings

The rumors have been around for weeks, if not centuries. People have trekked to Yellowstone from all corners of the planet, wondering…seeking…searching for answers. Inquiries have been made at multiple visitor center information desks. Park rangers have been accosted on trails by those in need of clarification. Sadly, enlightenment has yet to be attained.
What is this eternal question that has been posed by many, the answer to which seems to be just beyond the grasp of all? 

“At what elevation do elk turn into moose?” 

IMG_8508ElkCalf ThroughScreen Door
Elk calf through a screen door dimly - future moose? 
No one has actually ever seen a melk, nor does anyone really know at what optimal elevation this metamorphism actually occurs. Are there distinct “stages” through which elk must pass in order to obtain their mooseness?

ElkSkullWith Antlers
Elk antlers and skull - ghost of a melk?
The elevation range for melk is thought to be around 8000 feet above sea level, give or take a few inches. Alas, the Central Plateau of Yellowstone fits nicely into that criterion. For sure, there have been those who claim to have stumbled across a melk, perhaps in some remote thermal swampland or sluggish river drainage of backwater northern Wyoming and southern Montana (not sure what’s going on in Idaho, however). Grainy Kodak Instamatic photographs allegedly of melk have been furtively passed around in dingy mountain cabins and by the fading light of dying embers of midnight campfires. But these claims remain unverified; no legitimate photo has yet been published. 

And so I made the decision last week to launch my own late–summer quest, a quest that would take me into the back of beyond. I would, in the end, have nervously tiptoed through seething bubbling hot springs; noisily slogged hip–deep in festering leech–ridden wetlands; and treaded uneasily through the darkest grizzly–infested forests. Anyone who wanted to join me was welcome, and there were legions of those who were eager. OK,  there were only three, and they had no idea they were searching for anything until I clued them in. One sojourner insisted that we would also have to look for yeti while we were out there slogging and treading and tiptoeing, so we added those to our agenda. 

Ultimately, we all agreed our undertaking was becoming curiouser and curiouser. 

IMG_8512ElkCalf OnItsWay
Going somewhere?

Tuesday, August 23, 2011

Travertine On Bunsen Peak

In my previous post about hiking up Bunsen Peak I had wondered about a stunning white rock outcrop along with an ugly windowless wooden structure with lots of antennae protruding from it. Faithful blog follower THE AMAZING TRAVEL AGENT nailed the identity of the structure in his well-researched and timely comment. Sadly, no one ventured any ideas about the outcrop. I was pretty sure it was not of volcanic origin (but hey, what do I know?). It was up to me to peel away the layers of my own mental uncertainty concerning this mysterious geological deposit. 

IMG_8591 TravertineOutcropBunsenPeakTrail
Travertine outcrop on Bunsen Peak trail

I didn’t pay much attention to the outcrop on the ascent but simply marched right through it, intent on my two–mile assault of Bunsen Peak. However, a huge landslide of white boulders tumbling down from the mountainside across the Grand Loop Road did catch my attention. These large jumbled masses of rocky blocks are in an area called Silver Gate and are referred to as “the Hoodoos.” Earlier in the season I had learned that these rocks are travertine, a form of limestone or calcium carbonate which is common in hot springs located outside of the Yellowstone caldera, particularly in the Mammoth Hot Springs area. I could swing a cat from Bunsen Peak and it would land in Mammoth Hot Springs. Kitty cat might even go flying through the park superintendent’s window and land on his desk, since Mammoth is where park headquarters is located. I need to be careful with my aim if I choose to be swinging cats anywhere in the park, particularly on peaks. 

IMG_8554 MammothHot Springs
Mammoth Hot Springs from Bunsen Peak trail

Where was I before I started talking about swinging cats? 

Oh, right. Travertine. 

Inside the caldera, thermal features such as geysers and hot springs come up through a silica–rich volcanic rock called rhyolite. As the water of the hot spring cools enough for dissolved minerals to come out of solution, deposits of “siliceous sinter” or “geyserite” form. This geyserite is actually quartz with some extra water in it. 

However, outside the caldera (where Mammoth Hot Springs is located) the hot springs come up not through any silica–rich volcanic rock but through bedrock limestone. Deep underground the hot, acidic water has the ability to dissolve the calcium carbonate of the bedrock limestone. As the hot, calcium carbonate–rich water rises near the surface and the pressure on it drops, carbon dioxide gas escapes from solution (and in its own peculiar way contributes to global warming). It is at this point that the calcium carbonate precipitates as travertine terrace deposits. 

So as I head down the trail from Bunsen Peak I notice and examine this outcrop of white rock. I look across to the mountain across the road. I look back at the outcrop. I look back and forth for a few more minutes. Eureka! It’s got to be the same rock.

IMG_8573Terrace Mountain
Terrace Mountain and landslide deposits

IMG_8586 TravertineOutcropOnBunsenPeak _JanForScale
Travertine outcrop on Bunsen Peak trail - Jan for scale

After I got home I searched around in my own personal heap of Yellowstone reference material that covers nearly every horizontal surface in my apartment to see if I could find some sort of age for this travertine. I discover that the mountain I was gazing at across Grand Loop Road is called Terrace Mountain. It is an extinct travertine terrace; the travertine deposits there have been dated to around 374,000 years ago while the travertine deposits at Mammoth Hot Springs and nearby Gardiner, Montana have younger dates ranging from about 5,000–57,000 years ago. These are “disequilibrium ages” – if anyone can explain what that means I would really like to know! 

Two favorite Yellowstone references:
Christiansen, R.L., 2001, The Quaternary and Pliocene Yellowstone Plateau Volcanic Field of Wyoming, Idaho, and Montana, USGS Professional Paper 729-G.
Smith, R.B. and Siegel, L.J., 2000, Windows into the Earth – The Geologic Story of Yellowstone and Grand Teton National Parks

Saturday, August 20, 2011

Burning Up The Trail

What a difference twelve months makes! This time last year I was working at Katmai National Park and Preserve in Alaska, robotically lobbing pumice into Naknek Lake on my days off and wondering if I’d ever get to Novarupta. This summer I find myself in Yellowstone, and every weekend I discover some different area of the park to explore and some new trail to hike. Perhaps one major difference is that I have my car in Yellowstone, and there are over one thousand miles of trails just waiting for me to take advantage of the next “feet photo” opportunity. Trails were few and far between in Katmai. 

IMG_8565Lunch View
Feet with a view

My latest pick–of–the–week was Bunsen Peak, in the northwest section of the park just outside of Mammoth Hot Springs. Although Bunsen Peak is only 70 miles from Grant Village, the drive took an hour and a half due to the twisting, narrow park road and 45–mile–per–hour speed limit. A few miles south of the trailhead we spotted a grizzly bear crossing the road. There was little traffic at that early morning hour, just three or four cars including mine, but the grizzly appeared stressed as it zigged and zagged its way past us and disappeared down an embankment. Lucky for the frazzled grizzly there was scant time for the usual circus of wildlife–watching vehicles and their occupants to accumulate along the side of the road. 

Bunsen Peak rises to 8,564 feet above sea level, a remnant intrusive plug of dacitic igneous intrusion which formed during the Absaroka volcanic event of around 50 million years ago during the Eocene epoch. The eruption of Bunsen Peak is also related in time and volcanism to the activity of Mt. Washburn. According to “Yellowstone Place Names,” its name came about in 1872 during the second Hayden expedition. It was named for Robert Wilhelm Eberhard von Bunsen (indeed!) who was a chemist, the inventor of the spectroscope and the Bunsen electric cell, and (appropriately for geology) the discoverer of the elements cesium and rubidium, which have really long half–lives and so can be used to date really old rocks. Interestingly, “Yellowstone Place Names” states that the Bunsen burner was named for him but he was probably not the inventor. I will leave it to the astute WATCH FOR ROCKS reader to confirm or deny this allegation. 

IMG_8521Trail Through LodgepolePine
Lupines along the trail

IMG_8528Swan LakeInGardners Hole
Swan Lake and Gardners Hole; Gallatin Range in distance

The ascent to the summit is around 1,300 feet over 2.1 miles, so we were steady up and up. Along the way we stopped to look at nearly every rock, wildflower, and viewpoint. At this blistering pace, Jan and I burned our way to the top in a record two hours. I know one mile an hour might seem a bit slow for some of you, but hey! We had the time and we have the aging knees to amble at our leisure. We definitely were not interested in breaking any land–speed records while ascending 650 feet per mile. We had nowhere to go but up. 

IMG_8596Bunsen Peak
Trail to Bunsen Peak
But what the heck are these rocks?

IMG_8592 TravertineTerrace Deposits 
And what’s this windowless structure doing on top of the mountain? 

IMG_8556Park RadioTower

Stay tuned!

Some Favorite Resources:

Fritz, W.J., 1994, Roadside Geology of the Yellowstone Country

Smith, R.B. and Siegel, L.J., 2000, Windows into the Earth – The Geologic Story of Yellowstone and Grand Teton National Parks
Whittlesey, L.H., 2006, Yellowstone Place Names, 2nd edition revised