The Coprates Region
Topographical Map of the Coprates Region
We will start from the east and go west between 10-20°S:
We start our survey in the Sinai Planum Area. It is located 13°S 272°E and covers and area of 900 km.
Sample of Lineations on Southern Sinai Planum at 16°S 275°E.
A little north of this area is the Sinai Fossae at 14°S 282°E.
Sinai Fossae
Following this we head north and come into the Sinai Dorsa at 12°S 281 E.
Ridges and Troughs in Sinai Dorsa Region
Going northwest from there we enter the western part of the Melas Chasma at about 11°S 287°E.
Sulfates and Valley System in Melas Chasma Basin HiRISE DTM
Melas Chasma Blocky Floor
Around the edges of Melas Chasma is also a lot of slide material. This is also the deepest part of the Valles Marineris system at eleven kilometers deep from the surrounding surface, from here to the outflow channels are about a 0.03 degree slope upward to the northern plains, which means that if you filled the canyon with fluid, it would have a lake with a depth of one kilometer before the fluid would flow out onto the northern plains.
To the south of Melas Chasma as is the Nia Fossae at 14°S 287°E.
The Nia Fossae are the semi- circular troughs below Melas Chasma in this image by Themis
Going South of there we come to the Melas Dorsa at 18.5°S 287°E.
Shallowed Crater on Plains in the Melas Dorsa Region
The Melas Dorsa area is composed of a series or Wrinkle Ridges some of which you can see in this picture.
To the north of the western part Coprates Chasma is the Southern Ophir Planum Area at 10°S 295°E.
Potential Paleolake in Crater in Ophir Planum
Coprates Chasma is a huge canyon in the Coprates Region of Mars, located at 13.4° south latitude and 301°E longitude, part of the Valles Marineris canyon system. It is 966 km (600 mi) long and was named after a classical albedo feature name:
Coprates Chasma from 290.9 - 306.6°E.
Coprates Chasma fault as seen by HIRISE.
Layers in the rock face may be from volcanic, lacustrine, and/or Aeolian sediments deposited in Valles Marineris.
South Coprates Chasma Dune Changes HiRISE DTM
East Coprates Chasma Dune Fields and Wall Rock HiRISE DTM
South of Coprates Chasma is the Coprates Catena stretching from to 293°E to 303°E. at about 15°S.
Collapsed structures in the Coprates Catena
The Coprates Catena is a chain of collapsed structures, which run parallel to the main valley of Coprates Chasma. These collapsed structures vary between 2500 and 3000 meters deep, which is far less than the depth of the main valley at 8000 meters. A few landslides can be seen on the valley walls. The valley chains have no connection to the lowland plains as compared to the main valleys. This indicates that their origin is solely due to the expansion of the surface, or collapse, with removal of underlying material (possibly water or ice). On the valley floor, brighter layers are exposed, which could be material of the same composition as seen in other parts of Valles Marineris, where sulphates have been measured by the OMEGA spectrometer instrument on board Mars Express.
South of Coprates Catena is Arima Crater at 296°E 16°S.
Arima Crater
A perspective view of Arima Crater a 50 km diameter crater in Thaumasia Planum. The image was made by combining data from the High-Resolution Stereo Camera on ESA’s Mars Express with digital terrain models. The image was taken on 4 January 2013, during orbit 11467, and shows a close up view of the central ‘pit’ of this crater, which likely formed by a subsurface explosion as the heat from the impact event rapidly vaporized water or ice lying below the surface.
South of the eastern end of Coprates Chasma we come to Saravan Crater at 306°E 17°S
Saravan Crater is in the center of the Picture
Saravan Crater is 48 km in diameter and is named after a Laos place name.
The eastern end of the Coprates Chasma lets out into the Capri Chasma which goes north into the next Region to the East.
Hematite in Capri Chasma
Coarsely crystalline gray hematite is an iron oxide (Fe2O3) initially discovered from orbit by the instrument TES (Thermal Emission Spectrometer). TES has detected gray hematite in this area of Capri Chasma, one of several large depressions that make up the Valles Marineris canyon system. This HiRISE image shows light-toned units beneath darker mantles. At the Opportunity landing site in Meridiani Planum, the same gray hematite is found in millimeter size globules that have weathered out of the sulfate outcrop and become concentrated along upper soils. It is likely that the same scenario is taking place here in Capri with the hematite grains forming in the light-toned sulfates and then eroding out and concentrating in the darker mantle soils.
Possible Hematite in Capri Chasma HiRISE DTM
Capri Mensa
Capri Mensa is a mesa in the Coprates quadrangle of Mars at 14° south latitude and 313° East longitude. It is about 275 km in area and was named after a classical albedo feature name. It separates the Capri Chasma in the north from the Eos Chasma to the south.
Eos Chasma is a Chasma in the southern part of the Valles Marineris canyon system south of the Capri Mensa.
Eos Chasma
Eos Chasma’s western floor is mainly composed of an etched massive material composed of either volcanic or Aeolian deposits later eroded by the Martian wind.
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Bedrock on the floor of Eos Chasma
The eastern end of the Eos Chasma has a large area of streamlined bars and longitudinal striations. This is interpreted to be stream-carved plateau deposits and material transported and deposited by flowing fluid. Ganges Chasma is an offshoot of Eos Chasma. MRO discovered sulfate, hydrated sulfate, and iron oxides in Eos Chasma.
Hematite In Eos Chasma HiRISE DTM
Going further east we come to Eos Chaos. Eos Chaos is a rough, collapsed area in the Coprates Region on Mars at 16.8° south latitude and 311° East longitude. It is about 490 km long and was named after the Greek name of Aurora, an albedo feature.
Light-toned Layers in Eos Chaos
This image shows an outcrop of light-toned rock in Eos Chaos, a knobby region which transitions into the Eos Chasma. The outcrop is exposed in the wall of a mesa (a flat-topped, steep-sided plateau). The outcrop is prominent in the eastern part of the image. Most of the material is light and shows many small scarps or benches. In places these appear to indicate boundaries between layers, but they are often discontinuous. The light material is buried by a thin mantle of dark material in places; the dark material is from other rock layers.
Smooth Rounded Feature in Eos Chaos
Ultimately, the mesa is capped by a thin veneer of dark material with a rippled texture, forming most of the southern part of the image. These ripples likely formed by wind blowing sand or dust, but they may have become indurated (hardened) enough to become inactive, since they are not found within small craters on the mesa top.
We now Change direction and head back west between 20-30°S:
The area south of Eos Chasma and Eos Chaos is known as the Noachis Terra Area. This area extends all the way to the southern and eastern borders of the Coprates Region and is bordered on the west by the Thaumasia Planum.
Noachis Terra
Noachis Terra (lit. "Land of Noah") is an extensive southern landmass (terra) of the planet Mars. It lies west of the giant Hellas impact basin, roughly between the latitudes -20° and -80° and longitudes 30° west and 30° east, centered on 45°S 350°E. It covers an area of 4, 800 km.
At 25°S 312°E we come to Her Desher Vallis.
Source Region for Her Desher Vallis
Her Desher Vallis is 107 km in length and is the word for "Mars" in Egyptian Arabic.
Nirgal Vallis in Coprates Region
Nirgal Vallis is a long river channel bordering the Coprates Region, Phoenicis Lacus Region and Margaritifer Sinus Region of Mars at 28.4° south latitude and 42° west longitude. It is 496 km long and is named after the word for "Mars" in Babylonian. The western half of Nirgal Valles is a branched system, but the eastern half is a tightly sinuous, deeply entrenched valley. Nirgal Valles ends at Uzboi Vallis. Tributaries are very short and end in steep-walled valley heads, often called "amphitheater-headed valleys." The shape of these valley heads is like cirques on the Earth.
Ritchey Crater is a crater in the Coprates Region on Mars, located at 28.8° South and 309° East almost on the southern border of the Region.
Ritchey Crater
This image shows eroding layered deposits in Ritchey Crater, a large impact crater in the Southern highlands. Three general units are visible: a relatively dark upper layer, a light middle unit, and the floor material, which may be mostly obscured by dust. The dark cap layer appears to be relatively hard and resistant, while the light material is weak. Once the upper layer is removed, the light layer does not last long. If one looks at the sub image from the top center part of the image it shows this stack.
Sub Image of Ritchey Crater
The dark unit is thin and breaking into boulders. The light material is actually divided into smaller layers, and is pervasively fractured. However, the boulders falling from the edge are mostly small and rarely remain intact if they move more than a few meters. The cracking of the layer could be due to water loss from the layer, or to regional tectonic effects such as stresses from burial and erosion. The base unit is partially covered by wind-blown ripples. It is unclear how each of these layers formed. Volcanic ash layers, lake or stream deposits, or sandstone deposited by dunes can all produce horizontal layers. Unraveling the origin would provide important clues to Mars' past.
Colorful Rocks in Ritchey Crater
The Crater is 79 km in diameter and was named after George W. Ritchey, an American astronomer (1864-1945). Ritchey Crater is interesting to scientists because it displays several different layers. A dark layer at the top forms a cap rock that protects the underlying layers from erosion. Under this hard, dark layer is a softer, light-toned rock, that breaks into small boulders. The layers might be formed of volcanic ash, lake or stream deposits, or sand dunes.
Ritchey Crater HiRISE DTM
The area that separates the Noachis Terra from the Thaumasia Planum is the Nectaris Fossae, which is on the up hill slope leading to the Thaumasia Planum. Planum is Latin for Plateau, which puts the Thaumasia Planum at a higher elevation- roughly about 3000 meters higher.
Thermally Distinct Area in the Nectaris Fossae on upslope to Plateau
The Nectaris Fossae stretches from 17-29°S and 300-304°E. It is 637 km in length and is named after a classical albedo feature.
Thaumasia Planum and Vicinity
The Thaumasia Planum covers and area of 799 km and is named after a classic albedo feature. It extends from 15°S -28°S and 290°W to 299°E.
The first major Crater we come to on the Plateau heading west is Ibragimov Crater.
Ibragimov Crater
Ibragimov crater is named after the Azerbaijani and Soviet astrophysicist Nadir Baba Ogly Ibragimov. It is located at 26°S 300°E and is 86 km in diameter.
Going further west we come to the Felis Dorsa Area.
Felis Dorsa Area
The Felis Dorsa area is covered by ridges as seen in this photo. There seems to be a whole series of lateral ridges in this image going from west to east. Felis Dorsa is 753 km in area and is named after a classical albedo feature.
Going to the southeast we come to Mazamba Crater at 28°S 290°E.
Layers in Mazamba Crater
Mazamba Crater is 53.5 km in diameter and its name comes from a Mozambique place name.
Going west from Mazamba Crater we come to Melas Fossae, which roughly runs along 287°E from 23°S to 30°S.
Melas Fossae
Melas Fossae is about 568 km in diameter and is named after a classical albedo feature.
To the northwest is Toconao Crater at 21°S 285.5 E.
Distant Rampart of Toconao Crater
Toconao Crater is a small crater only 17.7 km in diameter it is named after a Chilean place name.
Going further west we enter the Solis Planum Area 280°E. It covers and area of about 1700 km and extends all the way to the western border of the Coprates Region. If we turn around and look back to the east in the direction we have come from we might see the following images:
The Solis Planum looking Southeast
The Solis Planum looking Northeast
How A Mission to Mars could really Happen:
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