アメリカ内務省さんのインスタグラム写真 - (アメリカ内務省Instagram)「The Yellow Mounds area of Badlands National Park in #SouthDakota reveals geologic history in vivid color. Shades of mustard and streaks of plum represent deposits of sediment settling here over different periods of time. About 500,000 years ago, the Cheyenne and White Rivers carved their way through this landscape. They are the reason for the narrow channels, canyons and rugged peaks we see today. Erosion continues to shape these hills. Scientists estimate that in the next 500,000 years, the #Badlands will erode away completely. So visit while you can! Photo @BadlandsNPS by Karen Smith (www.sharetheexperience.org). #NationalPark #usinterior」8月28日 9時10分