Welocome to the 30th street station located in downtown philadelpea PA!
To get credit for this Earth Cache, you will need to go the read and understand the full lesson, go to the posted cordinants, observe the lime stone on the building, answer the questions at the bottom of the description, and finnaly post picture proof that you were at the cordinants. Please do not post any spoiler pictures of the answers. Have fun!
The geolodgical feature that you will be learning about today, is a special type of lime stone called Indiana limestone. Indiana limestone, also known as Bedford limestone, is a type of sedimentary rock that was formed during the Mississippian period, of what scientists belive to be around 330-340 million years ago. During this time, the region that is now Indiana was covered by a shallow, warm sea. The sea was teeming with marine life, including coral, shellfish, and other organisms with calcium carbonate shells and skeletons. As these organisms died, their remains settled on the sea floor, gradually forming thick layers of sediment.
Over millions of years, these layers of marine sediments were buried under additional layers of sediment. The weight and pressure from the overlying materials caused the sediments to compact and cement together, a process known as lithification. The calcium carbonate from the shells and skeletons acted as a natural cement, binding the particles together to form solid rock. This process resulted in the creation of Indiana limestone, a dense and durable rock that is highly prized for its uniform texture and ease of carving.
This type of limestone has been extensively quarried and used as a building material since the early 19th century. Its fine grain and uniformity make it ideal for both structural and decorative purposes. Notable buildings constructed from Indiana limestone include the Empire State Building, the Pentagon, and the National Cathedral. The stone's ability to withstand weathering and its natural beauty have made it a popular choice for architects and builders across the United States, cementing its place in architectural history. Even some people use in there homes, as counter tops or any other thing that might be helpful.
Now here are the three questions that you will need to answer to get credit for the cache.
a) What is the apperance of the stone, what colors and veins do you notice?
b) What patterns and engraveings do you notice?
c) Post picture proof that you were there.