Photo Uploaded: Oct 18 2012 04:18:34 GMT Taken: 2012:08:16 14:19:52 Manufacturer: Canon Camera: Canon EOS REBEL T2i Aperture: F3.5 Shutter: 1/500 sec ISO: 100 Flash: No (Turned off)
My 2012 South Dakota Trip
Exploring the Black Hills of South Dakota.
We are now going down into the canyon. This wildlife trail is about a mile long hike, descending 140 feet to the Spearfish Falls at the bottom and spanning a 120 feet gorge.
Originally, a great sea covered this area. When the waters started to subside, the canyon was carved out by water eroding away the softer rock. The land was also pushed up from underneath by volcanic action. After many years, the water carved out the channel we have come to call "Spearfish Canyon".
The origins of the name "Spearfish" can be debated. Many people believe the Indians speared fish from Spearfish River (now called Spearfish Creek), hence the name.
The canyon consists of 3 main layers of rock. The highest peaks, typically the thickest part, which can be 300 to 600 feet thick, are known as the PahaSapa Limestone. It's typically beige or tan with weathered gray areas and it's in this section of rock where people find the most fossils.
The next level down is the Englewood Limestone, which can range from 30 to 60 feet thick. The Englewood Limestone is quite often mauve, pink or even red. The bottom layer is known as Deadwood Sandstone and is normally a brown color and may appear to have different levels or layers. These Deadwood Sandstone layers can be up to 400 feet thick!
The PahaSapa Limestone, found at the top layer of Spearfish Canyon gets its name from the Sioux Indian Nation. "Paha" meaning, "Hills", and "Sapa" meaning, "Black". If you look at the Black Hills from a distance, they appear quite dark. This is because of the ponderosa pine trees that make up almost 80% of the tree coverage here in the Hills. When you look closely at the needles of the Ponderosa Pine, you can see that they are flat. The topside of the needles are designed for absorbing light... thus the Hills look dark from a distance.