Sunday, August 26, 2007

A long day is done

Badlands1Although we only rode 400 miles today, it seemed a lot harded than the 570 we rode yesterday.  It was a lot warmer today.   We made it to Wall South Dakota.  Wall is famous for Wall Drug Store.  I’m not so sure what so wonderful about it.  It seems to be just a buch of small merchants in an old building.  I must admit that we were extremely tired and only spent a few minutes there.  There might be a lot that we didn’t see. 


The highlight of the day was going through the Badlands National Park.  It’s right outside of Wall South Dakota.



What are Badlands?
Badlands are semiarid regions with sparse vegetation that experience high rates of erosion. Water and wind, instead of carving gentle hills and broad valleys, sculpt soft sedimentary rock into intricate mazes of narrow ravines, v-shaped gullies, knife-sharp ridges, buttes, and colorful pinnacles. Badlands are found throughout the world; however, a special set of geological conditions must be present for the formation of badlands topography.


Badlands3


How Are They Formed?
For badlands to form, the land must be composed of alternating layers of hard and soft rocks and soil. When easily eroded material, such as clay or mud stone, is topped by more resistant material, such as sandstone, the harder horizontal layers offer some protection to the beds of soft deposits below. Uncovered layers of softer rocks or soil wash away quickly, while protected deposits form nearly vertical walls beneath the harder material.


The primary agent of weathering and erosion is usually water. Rain in these semiarid regions often falls in sudden, heavy showers. The water moves swiftly, washing down the exposed hills, loosening grains and particles of rock. Deep gullies and channels are the result.


The composition of the soft clay also has an effect on the rate of erosion. Badlands clay soaks up precipitation somewhat like a sponge. As it dries the exposed soil cracks and crumbles, leaving loose rubble several inches deep on the surface of the ground. This rubble begins to wash away immediately, often during the next severe storm. Lack of dense ground cover or heavy vegetation means there are no root systems to hold the soil and impede erosion.


Finally, the area being worn down usually lies well above the main drainage basin. When land is high water drains quickly, and the streams cut the bottoms of channels faster than the sides, forming deep and narrow ravines.


More on the Badlands


Badlands2


We also visited the Corn Palace in Mitchell South Dakota.  The building is sided with mostly corn cobs and hay and milo. in different designs.  They redo it every year with a new design.  It costs $130,000 to redecorate it every year.  Inside is a theater.  They’re having their Corn Palace Fesival this week.  Tonight’s concert:  The Oak Ridge Boys.  Last night, Weird Al Yankovic performed.  Several other name performers appeared.


Cornpalace1


Cornpalace2


We’re off to Mount Rushmore, Crazy Horse and maybe Needles Highway tomorrow. 

1 comment:

Anonymous said...

I'm originally from this area and if you need a good steak at the end of the day, check out Shoot the Bull in Spearfish, SD.