EARTHCACHING IS SIMPLE :
VISIT the site www.geocaching.com. READ the cache page. GO to GPS coordinates. LOOK at all the waypoints describe. ANSWER the questions. SEND your answers to the owner (never write them in your log) and then REGISTER.
Please contact me for any questions.
REMEMBER :
You only have to answer questions and no physical geocache to find !
GOVERNORS ISLAND
Governors island is a 172 acre in the heart of New York Harbour. It's only 800 yards from lower Manhattan and even closer to Brooklyn.
The giant granite scramble on Outlook Hill is made entirely of granite blocks from the old Island seawall. In 2012, The Trust replaced 1 mile of seawall with more resilient rip-rap revetment
The white seat-edge along the western faces of Discovery & Outlook hills are not only super comfy to sit on, they are also a resiliency measure to protect the Hills against wave action during projected flood events.
Governors island is accessible by ferry, during regular public hours and open to the public from May 1-October 31.
>> To know more about Governors island (visit link)
LOWER HUDSON GEOLOGY
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MANHATTAN BEDROCK
is composed of different kinds of metamorphic rocks.
Manhattan schists (yellow), calcite marble (orange), gneiss and amphibolite (brown) and Yonkers granite and gneiss (pink)
Metamorphic rock is a type of rock which has been changed by extreme heat and pressure. This causes profound physical and chemical change. The original rock may be sedimentary rock, igneous rock or an older metamorphic rock.
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>> To know more about Lower Hudson geology (vist link)
GRANITE
Granite is an igneous rocks formed from the solidification of molten rock material. There are two basic types.
Intrusive igneous rocks crystallize below Earth's surface, and the slow cooling that occurs there allows large crystals to form.
Extrusive igneous rocks erupt onto the surface, where they cool quickly to form small crystals.
To know more about igneous rocks (visit link)
Granite is a light-colored igneous rock with grains large enough to be visible with the unaided eye. It forms from the slow crystallization of magma below Earth's surface. Granite is composed mainly of quartz and feldspar with minor amounts of mica, amphiboles, and other minerals. This mineral composition usually gives granite a red, pink, gray, or white color with dark mineral grains visible throughout the rock.
The grain size is coarse enough to allow recognition of the major minerals. The pink grains are orthoclase feldspar, and the clear to smoky grains are quartz or muscovite. The black grains can be biotite or hornblende. Numerous other minerals can be present in granite.
Many people recognize granite because it is the most common igneous rock found at Earth's surface and because granite is used to make many objects that we encounter in daily life. These include counter tops, floor tiles, paving stone, curbing, stair treads, building veneer, and cemetery monuments. Granite is used all around us - especially if you live in a city.
Granite is the rock most often quarried as a "dimension stone" (a natural rock material that has been cut into blocks or slabs of specific length, width, and thickness). Granite is hard enough to resist abrasion, strong enough to bear significant weight, inert enough to resist weathering, and it accepts a brilliant polish. These characteristics make it a very desirable and useful dimension stone.
To know more about Granite rock (visit link)
YONKERS GRANITE
The most important granite and gneiss quarries are located in Westchester county in north of New York City, especially in Yonkers and Dunwoodie.
The city of Yonkers, will go down in history as one of the most prominent granite quarry locations in the US. Yonkers granite dominated the mansonry and construction industry not only in NYC, but in areas that stretched as far north as Canada and as far west as Chicago.
In terms of geology, "Yonkers gneiss" is the official term to describe the band of bedrocks that occurs in a long, narrow belt, and also in isolated bodies in southern Westchester. It also been known as Yonkers granite or Westchester granite.
The Yonkers gneiss outcrops lie in several areas. The principal belt within which most of the quarry were situated parallels the former Bronx River and Harlem Railroads, from a point south of Mont Vernon up to Hartsdale. A second area of the Yonkers gneiss extend along the axis of the main belt father north near Valhalla and the Kensico Reservoir.
The characteristics of Yonkers stone : rather fine in grain, and of slightly blueish grey color. This color become more of a pink on the cleavage surface within the quarry.
>> To know more about Yonkers granite (visit link)
QUESTIONS TO CLAIM THE CACHE
To claim this earthcache, please email me (DO NOT POST IN YOUR LOG) your answers to the following questions:
1. At the given coordinates (waypoint 1), please describe color, shape, texture and crystals size of the central block (A).
2. Using the information above, describe the characteristics of Yonkers granite.
3. On top of Outlook Hill (waypoint 2), please observe the higher rock (B) and describe your feelings when touch the stone : is it smooth or rough ? Now compare blocks (A) and (B) : do you think they are different or similar ? Explain why.
4. Please add 1 or more photo of yourself or your GPS with Statue of Liberty in the background. That request is NOT optional.