The cache coordinates place you in front of Umpire Rock, an outcrop in the middle of Central Park. An outcrop is simply a place where the earth's underlying rock (known as bedrock) is sticking up out of the soil. There are tons of outcrops all over Central Park. In fact, it's because the bedrock is so close to the surface in many areas of Manhattan that the city can so easily support and anchor our towering skyscrapers. In other places, it's much more difficult to drill down to the bedrock and anchor the foundation of these huge buildings.
Challenge #1 - Find Umpire Rock
First, did you find Umpire Rock? Take a photo of you and your GPS with Umpire Rock in the background. Post the photo with your log. Also, do some research and answer the question below. Email me the answer. Don't post the answer with your log.
What is the name of the type of bedrock in this area?
Go ahead and climb up onto the rock and take a look around. One of the reasons that Central Park is so inspiring is the striking juxtaposition of nature and the hectic city skyline looming over it. It's very hard to imagine this overlook without the city as a backdrop. Try to imagine time flowing backwards. The towers begin to deconstruct. Central Park's paths and fences give way to wilderness. The street grids fade away. Soon there is the sound of the forest instead of sirens and only an occasional visitor from the southern settlement. Eventually you'd only see the Lenape roaming the area and then no mark of civilization at all. Go back further, 20,000 or so years, and you may witness the last of many great glacial surges that shaped the land around you.
A glacier is a huge mass of ice that because of its own weight and gravity slowly flows outwards and downwards. While moving it picks up and drags rocks across the landscape gouging out grooves. When it thaws and starts to recede, the glacier drops rocks and boulders that it may have carried from miles away. Umpire Rock is a prime location to observe these effects of glaciers.
Challenge #2 - Glacial Grooves/Striations
Examine Umpire Rock and find an example of small glacial grooves or "striations" carved into the outcrop. It may be difficult to determine whether you're looking at true glacial striations or just the outcrop's natural bedding which can also be grooved. A good test is to check whether the striations are linear, parallel, and oriented in a different direction than the bedding. If you're having a hard time, take a look at the drawing included in this description that points out some good areas to find striations. Take a photo of what you find including your GPS device and post it in your log. Also, examine the striations and answer the question below. Email me the answer. Don't post the answer with your log.
In what direction are the striations carved? What does this say about the movement of the glacier?
Challenge #3 - Erratics
An erratic is a rock that was carried by a glacier to its present location and therefore usually differs in composition from the rocks native to the area. Explore Umpire Rock further and try to find an example of an erratic. If you're having a hard time, take a look at the picture included in this description that points out some good areas to find erratics. Take a photo of what you find including your GPS device and post it in your log. Also, do some research and answer the question below. Email me the answer. Don't post the answer with your log.
What is the largest known erratic in the world? What's the waypoint of the EarthCache dedicated to it?
To get credit for this cache, post your 3 photos with your log and email me the three answers. The photos MUST have your GPS in them. If you log the cache without following these requirements, I'll have to remove your log.
A Warning About the EarthCache Site
Central Park is officially open between 6:00am and 1:00am. The park is safe, but late at night there aren't as many people around. Don't visit the park alone late at night. Use common sense and if something doesn't feel right trust your judgment and don't put yourself in a bad situation. And finally, this is a big outcrop we're talking about here. It has some steep sides and dangerous drop offs. Please be careful when you're up there. OK, enough of that! Have fun!
Umpire Rock Drawing