Congratulations to USAdotRun on the FTF!!
This is an Earthcache. There is no container hidden for this type of geocache. Instead, it is an educational cache in which you answer questions about a geologic feature at the listed coordinates to get credit for the cache.
To claim a find for this cache, send your answers to the questions at the end of the educational material to the CO. Please don’t include the answers to the questions in your log.
Types of Rocks
The main types of rocks are igneous, sedimentary, and metamorphic.
Igneous rocks form when hot magma or lava cools and solidifies. They are characteristically very hard. Igneous rocks that formed by slow cooling, such as granite, contain a mixture of crystalline minerals. Igneous rocks that cooled quickly can be more uniform and smooth such as obsidian.
Granite Rock Example: Obsidian Example:
Sedimentary rocks are formed when sediments in water settle to the bottom and are compacted over time. The sediments can include sand, mud, or the remains of small aquatic plants and animals. Sedimentary rock is often seen in places that were once covered by ancient lakes. These rocks usually have visible layers and may contain fossils. Examples include sandstone and limestone.
Example of Sandstone:
Metamorphic rocks are formed when igneous or sedimentary rocks are transformed deep in the earth by intense heat or pressure. They often have uneven layers of varying minerals compacted together into differently colored bands. An example is Gneiss.
Example of Gneiss:
Erosion of Rocks
Many environmental factors lead to erosion of rocks like you see in front of you.
Biological weathering occurs when plants begin attaching to and living on rocks. Lichens, fungi, and algae can grow on the surface where they can extract minerals and other nutrients. This process begins breaking down the rock. Larger plants like ferns or small trees can extend their roots into existing cracks, exerting enough pressure to begin prying the rock apart. Decaying plant matter creates acids that can weaken the rock. In addition to plants, animals and insects can contribute to erosion by burrowing into weakened or soft rock.
Example of Biological Weathering:
Physical weathering is also an important cause of erosion. Water from rain and melting snow can wash away small particles. Water that has seeped into small cracks, expands as it freezes, enlarging the cracks and weakening the rock. Wind can cause abrasion of the rocks and blow away small particles. Flowing water from rivers, streams, or waves can break off pieces of rocks and carry them away. The particles being carried by the water can scrape against rocks that it hits causing additional erosion.
Example of Physical Weathering:
Seismic activity or earthquakes can lead to rock erosion by causing fracturing of rocks. Cracks that form can be more vulnerable to biological and physical weathering.
Example of cracking from seismic activity:
To claim a find for this cache, send your answers to the following questions to the CO. Please don’t include the answers to the questions in your log.
- Which of the main types of rock described in the discussion above do you see here? Explain your answer.
- Name two sources of erosion that are acting on this rock. Describe the evidence that you see that led you to this answer.
- Include a photo of yourself or a personal item in your log. No need to include your face in the photo.
IATCC is the cache designation to highlight a series of EarthCaches along the Ice Age National Scenic Trail grouped into a special category called "ColdCache" (IATCC). Find more information on the Ice Age Trail Alliance's ColdCache page.
Further Reading:
https://www.amnh.org/explore/ology/earth/if-rocks-could-talk2/three-types-of-rock
https://opengeology.org/
https://education.nationalgeographic.org/
