A Buried Crater?

This regional overhead view compares the crater nicknamed "Thira" on the top right with a crater on the bottom left that is buried by possible lava or debris flows. Thira Crater seems to have formed more recently due to its defined edges and features. The other crater exhibits edges that appear to have been buried. The "Columbia Hills" are seen to the left of Thira Crater for context. The blurriness in the lower right portion of this image is a result of missing data. This image was taken by the thermal emission imaging system on NASA's orbiting Mars Odyssey.