The Door Trail. Take a short walk along the wheelchair accessible boardwalk from parking and discover how a badland is created. Be prepared, especially in summer, with water, sunscreen and a hat. Beware of rattlesakes in the area. You may choose to go beyond the boardwalk at the end and take a hike through the Badlands desert but it is not required for this earthcache.
In order to log this earthcache please message me or email me the following information:
1. Look at the formation directly in front of you at the posted coordinates. Estimate its height and length.
2. Turn around and look at the formation behind you. Compare and contrast the two. Are they similar or different?
3. Describe the texture and appearance of the rock in this formation - what type of rock is it and why is it unique?
4. As you drove to this area along the highway (from either direction) you will have seen lots of badlands along the way. How do the badlands you have already seen differ in color or shape from the ones located here?
Badlands are typically found in areas of dry terrain where softer sedimentary rocks and clay-rich soils have been extensively eroded by wind and water. Badland formations occur on every continent and are characterized by steep slopes, minimal vegetation and high drainage. Canyons, ravines, gullies, buttes, mesas, hoodoos and other such geologic forms are common in badlands. Most badlands are difficult to navigate by foot. Badlands often have a spectacular color display that can include yellow, grey-green, brown or tan, dark black or blue and bright reds.
The badlands are formed by accumulation of layers of mineral materials, over time, and then erosion of those layers. Different environments deposit different sorts of clays, silts, and sand. The badland deposits here in South Dakota came from three major geologic periods (the Cretaceous Period, the Late Eocene, and the Oligocene Epochs), resulting in clear, distinct layers of sediment. Once the sediments have solidified, the sedimentary material becomes subject to erosion.
During the late Cretaceous period, volcanoes erupted west of this location and spewed ash that was carried by the wind to this area where it washed into wet areas of lakes and lagoons. Over time the ash was transformed into greyish, bentonite clay layers that can be seen today in the badlands areas. The bentonites in the badlands can absorb up to several times their weight in water and they are extremely slick and mobile when wet as they turn into a thick mud-like substance. They form a popcorn-like surface when dry.
It is sometimes erroneously taught that badlands erode at a steady rate of about 1 inch per year. In actuality, the precise process varies depending on the specific sedimentary material that was deposited. Studies are underway to determine more exactly how quickly each of the various badlands formations are eroding.
The native Lakota people were the first to call this place "mako sica" or "land bad." Extreme temperatures, lack of water, and the exposed rugged terrain led to this name. In the 1700's, French-Canadian fur trappers called it "les mauvaises terres à traverser," or "bad lands to travel through."