Saturday, January 22, 2011

Geology of Skiing - Hickory Ski Center

This is an attempt to bring together three professional and extracurricular passions: skiing, GIS, and geology. I think I'm going to try and produce a number of these for a few of my favorite local ski areas, but my favorite ski mountain must come first!

Skiing:

The weather has cooperated and I've been lucky enough to ski my favorite little mountain in upstate New York after its grand re-opening; the last time I skied at Hickory Ski Center was the fall of 2003 and in the intervening years I either haven't made it back over or it wasn't open. I wish I could claim I grew up skiing Hickory but I wasn't introduced until I was a Junior at SUNY Albany by my friends Craig and Jeff - a big thank you to both of them! For us interlopers, Hickory is best known for its steep terrain, lack of snow making and grooming, and only opening it's doors on the weekends and holidays. But the retro-style lodge with a circular fire pit, perfect for roasting hot dogs, and the deafening silence you find on the slopes both round out a close second in my opinion. Seriously, without snowmaking, high speed quads, snowcats on the prowl and few snowmobiles, it is unbelievably quiet!



It is one of the few remaining mountains in the east where you can find steep expert terrain while also enjoying an overwhelming family atmosphere. It's one thing to tell people the skiing is good, but I decided to create some visualizations using a GIS to help convince anyone who is skeptical.

3D Visualizations:

I created a suite of maps depicting the topography, slope, and 2ft aerial photography. This is a general location map of the ski center and view of the overall topography of the surrounding area:

HIckory Map

Topgraphy
Shaded relief map depicting topography in the Hickory Ski Center area

And these three orthophoto renderings give some perspective on the layout of the runs and just how much relief there is between the Hudson River and the summit!

Hickory Summit
View looking north down the face of the mountain towards the Hudson River


Orthophoto
View looking south across the Hudson River towards Hickory Ski Center


Orthophoto
View looking southeast across the Hudson River towards Hickory Ski Center

These two slope maps best illustrate the point of how steep Hickory is near the summit and how special it is in this particular region, it (and the other two 'Sisters') really stands out relative to the more subdued surrounding landscape.

Slope landscape
View looking southeast at a slope map of the area surrounding Hickory Ski Center

Slope
View looking southwest at a slope map of the area surrounding Hickory Ski Center

Hopefully these images give a sense of just how steep the runs are on the upper mountain and offers a sneak preview of the views you might catch from the summit! To create these visuals I obtained a 10-meter digital elevation model (DEM) and 7.5' USGS digital raster graphic (DRG) of Warrensburg, NY from the Cornell University Geospatial Information Repository (CUGIR) and 2ft digital orthophotos (DOQ) from the NYSGIS Clearinghouse.

Geology:

Last but not least, the geologic history of the region that Hickory calls home primarily exposes pre-Cambrian rocks associated with the Grenville Orogeny - a mountain building event similar to what is happening in the Himalaya's today. The map below depicts a simplified reconstruction of the North American continent during is mountain building event. A common saying about the Adirondack Mountain region is that while the mountains are relatively young (~30 million years) the rocks are very old (~1.9 billion years). For a more rigorous discussion of the relationship between the Adirondack's and the Grenville Orogeny you can read McLelland et al. (1996).

Source: http://instruct.uwo.ca/earth-sci/300b-001/rodkarl2b.jpg

These two maps depict the bedrock and surficial geology of the immediate area around the Hickory Ski Center, which indicates that all those bedrock exposures and ledges on the upper slopes are primarily a biotite and/or hornblende gneiss and the surficial material is exclusively glacial till. Interestingly (to someone who likes surficial deposits), there are lacustrine (lake) sands found along the floodplain of the Hudson almost up to the entrance into the Hickory Ski Center, likely a result of "Glacial Lake Warrensburg" described by Miller (1921) and later discussed by Connally and Sirkin (1971) and kame deposits (might look like gravel) on both sides of the river adjacent to the entrance, indicative of a depositional environment along a stagnant ice marge. This makes a lot of sense when you look at the steep faces of the Three Sisters, they likely shed sediment onto the ice lobe and when it stagnated and melted out, it left behind these deposits.

Bedrock GeologySurficial Geology

The datasets used to create these maps were obtained from the New York State Museum GIS data center. The underlying data was mapped at 1:250,000 so these aren't particularly high-resolution map products but they'll suffice for a general discussion of the local geology in this area.

Summary:

Hickory is pretty awesome if you have the legs to ski it; it can be pretty demanding and you're likely to get a few 'scratches' in your skis and you might have a sore spot from the 'caressing touch' of the Poma lifts, but it will be SO worth it. I hope the visualizations are useful for folks who have heard of Hickory but weren't convinced, for folks who haven't heard about, hopefully you're intrigued now! The geology on the slopes themselves are fairly unexciting, even to a geologist - gneiss is nice and till is, well till. But once the till is covered with snow it becomes a skiers Disneyland!

Monday, January 17, 2011

Knob and Kettle Topography - Black Earth, Wisconsin

The drive out to Montana this past summer (2010), took me through Wisconsin, home to numerous well-preserved and really cool glacial landforms. I had always wanted to visit the Ice Age Trail, which follows the terminal margin of the last glaciation in Wisconsin, and that side trip took me through some beautiful farmland with a unique topgraphy. This is a Photosynth I took near the town of Marxville, WI looking to the northwest across a field with this characteristic knob and kettle topography.



These are a series of simple three-dimensional maps I created to provide a birds-eye-view of this deglaciated landscape while comparing a few of the open-source alternatives out there:

Black Earth, Wisconsin
USGS DRG draped over 10-meter DEM - (Black Earth, Wisconsin)

Black Earth, Wisconsin
An attempt at draping the same DRG over the same DEM - (Black Earth, Wisconsin)

The product out of ArcScene is visually more compelling than the NVIZ version, I still can't figure out why the DRG is so pixelated in NVIZ. NVIZ was accessed through the GUI-driven GRASS available in QGIS ('Copiapo'). What I do like about NVIZ (besides being open-source) is that you can actually add an arrow (easily) and scale bar (which isn't all that great) into the 3D scene (seriously ESRI, how long has it been?). The red point in all the scenes is where the photo was taken looking to the northwest.

I am in the midst of trying to create similar 3D images using CapaBuilder and IDV, but so far I haven't figured these two out!