This image was taken by NASA (National Aeronautics and Space Administration) Mars Global Surveyor, capturing the Kasei Valles. Taken on June 4, 1998. An image that gives a glimpse of the complexity of Mars’ geological history. The circular terrain visible in the center is a 6km diameter crater that was once buried underground.
The Kasei Valley is a canyon carved by a flood that occurred over a billion years ago on a relatively flat plain. The crater shown in the image is what was buried in the plain and was partially dug up by the flood.
These images were taken by NASA’s Mars probe Viking 1. The first image captures a wide area of the Kasei Valley, and the white frame indicates the range of the second image and the opening image. The white frame of the second image is the range of the first image. Looking at the second image, you can see that the buried crater is at the edge of the mesa (table-shaped plateau). It seems that the crater edge did not break because the crater edge was high and the flood might not be overcome, and the flood was short.
This crater was probably formed by a meteorite impact 3.5 billion years ago and has since been buried beneath the plains. The sharp edges of the cliffs indicate that the bedrock that makes the mesa is made of hard rock. However, the crater seems to have been buried in its original shape because the process of being buried was slow.
