Chaotic terrain in Ariadnes Colles

Mars exhibits numerous 'chaotic terrains'. These are areas with an apparently inordinate accumulation of rocks of varying sizes and flat-topped features.

Ariadnes Colles is one such chaotic terrain located in the planet's southern highlands. It covers an area of 180 x 160 sq km, roughly half the size of Estonia. These images show the northwestern part of the region. Most of the area pictured is dominated by erratically shaped rocks that are 1-10 km in size. These are lighter in colour compared to their surroundings. Some larger blocks appear similar to mesa, a flat-topped natural feature found on Earth, and can reach a height of 300 m.

A striking lineation on the surface of the blocks (visible upon zooming in) is oriented in the northwest-southeast direction. The northwestern flanks have been eroded more strongly than the opposing southeastern ones. Wrinkle ridges, which form due to tectonic compression, are visible in the southwestern part. These ridges mark the western boundary of Ariadnes Colles.

In contrast to other chaotic terrains such as Iani Chaos, Adrianes Colles is not a water-source region. It is still debated, therefore, whether Ariadnes Colles was formed by the action of water or wind. The darker material in the southern areas is most likely sand or volcanic ash; some slopes of the flat-topped features have been covered by this dark material that was blown up on the slopes.

A large impact crater, 1200 m deep, is visible on the right. It shows a smaller crater superimposed on it. The larger crater is about 30 km in diameter and covers an area roughly the size of Hamburg. The smaller younger crater lies almost at the centre of the older one, and has a diameter of just 10 km. The colour scenes have been derived from the three HRSC-colour channels and the nadir channel. The perspective views have been calculated from the digital terrain model derived from the stereo channels.

Credit: ESA/DLR/FU Berlin (G. Neukum)
High resolution image

Nadir view of Ariadnes Colles.




Credit: ESA/DLR/FU Berlin (G. Neukum)
High resolution image

This ortho-image was rectified using elevation data derived from a high-resolution Digital Terrain Model, or DTM (obtained from HRSC data), such that distortions introduced during imaging are corrected. Such an image can be used to derive maps. Elevation data from the DTM has been colour-coded and overlain on the ortho-image so that elevation data and the image itself are displayed in a single scene. The scale is in metres.




Credit: ESA/DLR/FU Berlin (G. Neukum)
High resolution image

Perspective view of Ariadnes Colles.




Credit: ESA/DLR/FU Berlin (G. Neukum)
High resolution image

Most of the area pictured is dominated by erratically shaped rocks that are 1-10 km in size (1). These are lighter in colour compared to their surroundings. Some larger blocks appear similar to mesa, a flat-topped natural elevation, and can reach a height of 300 m (2). A striking lineation on the surface of the blocks (visible upon zooming in) (3) is oriented in the northwest-southeast direction. The northwestern flanks have been eroded more strongly than the opposing southeastern flanks. Wrinkle ridges, which form as a result of tectonic compression, are visible in the southwestern part (4). These ridges mark the western boundary of Ariadnes Colles. In contrast to other chaotic terrains such as Iani Chaos, Adrianes Colles is not a water source region. This is why it is still debated whether Ariadnes Colles formed by the action of water or wind. The darker material in the southern parts is most likely sand or volcanic ash; some slopes of the flat-topped features have been covered by this dark material that was blown up on the slopes (5). A large impact crater, 1200 m deep, is visible on the right (6). It shows a smaller crater superimposed on it. The larger crater is about 30 km in diameter and covers an area roughly the size of Hamburg. The smaller younger crater lies almost at the centre of the older one, and has a diameter of just 10 km.

Source: European Space Agency
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