Geological time scales
Autumn in the desert--Cottonwoods in a watercourse, along the road (Hwy 211) to the Needles section of Canyonlands National Park. These trees grow in areas of perennial water. When the climate changes and water isn't available for many years, the trees die. So they are an indicator of current rainfall conditions on a time scale of decades or centuries. The current shape of the spire above (North Six Shooter Peak) reflects a far longer time period of erosion, on the scale of a million years or a bit less. In turn, the rock strata in the pyramid formed over a still longer time frame, many millions of years.
Geological time scales
Autumn in the desert--Cottonwoods in a watercourse, along the road (Hwy 211) to the Needles section of Canyonlands National Park. These trees grow in areas of perennial water. When the climate changes and water isn't available for many years, the trees die. So they are an indicator of current rainfall conditions on a time scale of decades or centuries. The current shape of the spire above (North Six Shooter Peak) reflects a far longer time period of erosion, on the scale of a million years or a bit less. In turn, the rock strata in the pyramid formed over a still longer time frame, many millions of years.