Echus Chasma

The data was acquired on 25 September 2005. The pictures are centred at about 1° north and 278° east and have a ground resolution of approximately 17 m/pixel.
Echus Chasma is an approximately 100 km long and 10 km wide incision in the Lunae Planum high plateau north of Valles Marineris, the 'Grand Canyon' of Mars. Echus Chasma is the water source region of Kasei Valles, which extends thousands of kilometres to the north, and its southern-most part.

Echus Chasma is bounded to the west by the Echus Chasma plateau which lies about 4 km above the Echus Chasma floor. On the plateau are deeply incised valleys which connect to the Echus Chasma valley.

The images of the Echus Chasma plateau show valleys that are about 10 km long and 1000 m deep. The main valley, Kasei Valles, is about 4 km in depth. The smaller valleys, also called sapping canyons, originate from the discharge of groundwater.

One possible indication for volcanic activity in the past is be a sickle-shaped, about 25-km long dike in the centre of the image (feature 2 in the annotated image). Dikes are rock formations of volcanic origin. They are formed when magma rises up through fissures in the overlying rock or penetrates existing rock layers. The magmatic rock is usually resistant to weathering and is able to endure erosion.

Two impact craters with a diameter of approximately 8 km are located south-east of the dike. The eastern crater was partly eroded as the valley formed. A large portion of the crater collapsed into the valley and its debris was removed.

The dark material shows a network of light-coloured, shallowly incised valleys. They look similar to drainage networks known on Earth.

A 4000-m-high cliff marks the edge of the source area of Kasei Valles in its western part. Gigantic water falls may have once plunged over these cliffs on to the valley floor. The original shoreline is still partially visible. The remarkably smooth valley floor was later flooded by basaltic lava.

Images acquired in different orbits were combined to create the image mosaics, the map, as well as the colour-coded elevation model.

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 (1.4 MB).

Echus Chasma, nadir view.




Credit: ESA/DLR/FU Berlin (G. Neukum).
High resolution image (1.0 MB).

Perspective view of Echus Chasma.




Credit: ESA/DLR/FU Berlin (G. Neukum).
High resolution image (1.3 MB).

The 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 (1.4 MB).

The dark material shows a network of light-coloured, incised valleys that look similar to drainage networks known on Earth. It is still debated whether the valleys originate from precipitation, groundwater springs or liquid or magma flows on the surface.




Credit: ESA/DLR/FU Berlin (G. Neukum).
High resolution image (1.1 MB).

An impressive cliff, up to 4000 m high, is located in the eastern part of Echus Chasma. Gigantic water falls may once have plunged over these cliffs on to the valley floor. The remarkably smooth valley floor was later flooded by basaltic lava.

Source: European Space Agency
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