Coordinates | 15°00′N202°30′W / 15°N 202.5°W |
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The Elysium quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Elysium quadrangle is also referred to as MC-15 (Mars Chart-15). [1]
The name Elysium refers to a place of reward (Heaven), according to Homer in the Odyssey. [2]
The Elysium quadrangle covers the area between 180° to 225° west longitude and 0° to 30° north latitude on Mars. The northern part of Elysium Planitia, a broad plain, is in this quadrangle. The Elysium quadrangle includes a part of Lucus Planum. A small part of the Medusae Fossae Formation lies in this quadrangle. The largest craters in this quadrangle are Eddie, Lockyer, and Tombaugh. The quadrangle contains the major volcanoes Elysium Mons and Albor Tholus, part of a volcanic province of the same name, as well as river valleys—one of which, Athabasca Valles may be one of the youngest on Mars. On the east side is an elongated depression called Orcus Patera. A large lake may once have existed in the south near Lethe Vallis and Athabasca Valles. [3]
The InSight lander touched down in the southern part of this quadrangle in 2018 to conduct geophysical studies.
The Elysium quadrangle contains the volcanoes Elysium Mons and Albor Tholus.
David Susko and his colleagues at Louisiana State University analyzed geochemical and surface morphology data from Elysium using instruments on board NASA's Mars Odyssey Orbiter (2001) and Mars Reconnaissance Orbiter (2006). Through crater counting, they found differences in age between the northwest and the southeast regions of Elysium—about 850 million years of difference. They also found that the younger southeast regions are geochemically different from the older regions, and that these differences related to igneous processes, not secondary processes like the interaction of water or ice with the surface of Elysium in the past. "We determined that while there might have been water in this area in the past, the geochemical properties in the top meter throughout this volcanic province are indicative of igneous processes," Susko said. "We think levels of thorium and potassium here were depleted over time because of volcanic eruptions over billions of years. The radioactive elements were the first to go in the early eruptions. We are seeing changes in the mantle chemistry over time." "Long-lived volcanic systems with changing magma compositions are common on Earth, but an emerging story on Mars," said James Wray, study co-author and associate professor in the School of Earth and Atmospheric Sciences at Georgia Tech. Overall, these findings indicate that Mars is a much more geologically complex body than originally thought, perhaps due to various loading effects on the mantle caused by the weight of giant volcanoes. For decades, we saw Mars, as a lifeless rock, full of craters with a number of long inactive volcanoes. We had a very simple view of the red planet. Finding a variety of igneous rocks demonstrates that Mars has the potential for useful resource utilization and a capacity to sustain a human population on Mars. "It's much easier to survive on a complex planetary body bearing the mineral products of complex geology than on a simpler body like the moon or asteroids." [4] [5]
Much of the area near the volcanoes is covered with lava flows, some can even be shown approaching, then stopping upon reaching higher ground. (See pictures below for examples) Sometimes when lava flows the top cools quickly into a solid crust. However, the lava below often still flows, this action breaks up the top layer making it very rough. [6] Such rough flow is called aa.
Research, published in January 2010, described the discovery of a vast single lava flow, the size of the state of Oregon, that "was put in place turbulently over the span of several weeks at most." [7] This flow, near Athabasca Valles, is the youngest lava flow on Mars. It is thought to be of Late Amazonian Age. [8] Other researchers disagree with this idea. Under Martian conditions lava should not stay fluid very long. [3]
Some areas in the Elysium quadrangle are geological young and have surfaces that are hard to explain. Some have called them Platy-Ridged-Polygonized terrain. The surface has been suggested to be from pack ice, basalt lava, or a muddy flow. Using HiRISE images the heights of the ridges of the surface were measured. Most were less than 2 meters. This is far smaller than what is expected from lava flows. The high resolution photos demonstrated that the material seemed to flow which would not occur with pack ice. So, the researchers concluded that muddy flows cover the surface. [9]
So-called "rootless cones" are caused by explosions of lava with ground ice under the flow. [10] [11] [12] The ice melts and turns into a vapor that expands in an explosion that produces a cone or ring. Features like these are found in Iceland, when lavas cover water-saturated substrates. [13] [11] [14] [15] [16] [17]
The Elysium Fossae contain layers, also called strata. Many places on Mars show rocks arranged in layers. Sometimes the layers are of different colors. Light-toned rocks on Mars have been associated with hydrated minerals like sulfates. The Mars rover Opportunity examined such layers close-up with several instruments. Pictures taken from orbiting spacecraft show that some layers of rocks seem to break up into fine dust; consequently these rocks are probably composed of small particles. Other layers break up into large boulders, so they are probably much harder. Basalt, a volcanic rock, is thought comprise the layers that form boulders. Basalt has been identified on Mars in many places. Instruments on orbiting spacecraft have detected clay (also called phyllosilicates) in some layers. Scientists are excited about finding hydrated minerals such as sulfates and clays on Mars because they are usually formed in the presence of water. [18] Places that contain clays and/or other hydrated minerals would be good places to look for evidence of life. [19]
Rock can be formed into layers in a variety of ways. Volcanoes, wind, or water can produce layers. [20] Layers can be hardened by the action of groundwater. Martian ground water probably moved hundreds of kilometers, and in the process it dissolved many minerals from the rock it passed through. When ground water surfaces in low areas containing sediments, water evaporates in the thin atmosphere and leaves behind minerals as deposits and/or cementing agents. Consequently, layers of dust could not later easily erode away since they were cemented together.
The Elysium quadrangle is home to large troughs (long narrow depressions) called fossae in the geographical language used for Mars. Troughs are created when the crust is stretched until it breaks. The stretching can be due to the large weight of a nearby volcano. Fossae/pit craters are common near volcanoes in the Tharsis and Elysium system of volcanoes. [21] A trough often has two breaks with a middle section moving down, leaving steep cliffs along the sides; such a trough is called a graben. [22] Lake George, in northern New York State, is a lake that sits in a graben. Pits are produced when material collapses into the void that results from the stretching. Pit craters do not have rims or ejecta around them, like impact craters do. Studies have found that on Mars a fault may be as deep as 5 km (3.1 mi); that is, the break in the rock goes down to 5 km. Moreover, the crack or fault sometimes widens or dilates. This widening causes a void to form with a relatively high volume. When material slides into the void, a pit crater or a pit crater chain forms. On Mars, individual pit craters can join to form chains or even to form troughs that are sometimes scalloped. [23] Other ideas have been suggested for the formation of fossae and pit craters. There is evidence that they are associated with dikes of magma. Magma might move along, under the surface, breaking the rock, and more importantly melting ice. The resulting action would cause a crack to form at the surface. Pit craters are not common on Earth. Sinkholes, where the ground falls into a hole (sometimes in the middle of a town) resemble pit craters on Mars. However, on the Earth these holes are caused by subsurface limestone being dissolved, thereby causing a void. [23] [24] [25] The images below of the Cerberus Fossae, the Elysium Fossae and other troughs, as seen by HiRISE are examples of fossae.
Knowledge of the locations and formation mechanisms of pit craters and fossae is important for the future colonization of Mars because they may be reservoirs of water. [26]
Methane has been detected in three areas on Mars, one of which is in the Elysium quadrangle. [27] This is exciting because one possible source of methane is from the metabolism of living bacteria. [28] However, a recent study indicates that to match the observations of methane, there must be something that quickly destroys the gas, otherwise it would be spread all through the atmosphere instead of being concentrated in just a few locations. There may be something in the soil that oxidizes the gas before it has a chance to spread. If this is so, that same chemical would destroy organic compounds, thus life would be very difficult on Mars. [29]
Impact craters generally have a rim with ejecta around them, in contrast volcanic craters usually do not have a rim or ejecta deposits. As craters get larger (greater than 10 km in diameter) they usually have a central peak. [30] The peak is caused by a rebound of the crater floor following the impact. [31] Sometimes craters will display layers. Since the collision that produces a crater is like a powerful explosion, rocks from deep underground are tossed unto the surface. Hence, craters can show us what lies deep under the surface.
Research published in the journal Icarus has found pits in Zunil Crater that are caused by hot ejecta falling on ground containing ice. The pits are formed by heat forming steam that rushes out from groups of pits simultaneously, thereby blowing away from the pit ejecta. [32]
Some of the valleys in the Elysium quadrangle seem to start from grabens. Granicus Vallis and Tinjar Vallis begin at a graben that lies just to the west of Elysium Mons. Certain observations suggest that they may have been the location of lahars (mudflows). The graben may have formed because of volcanic dikes. Heat from the dikes would have melted a great deal of ice. [33] Two valley systems, the Hephaestus Fossae and Hebrus Valles, have sections that join and branch at high angles. [34]
The Athabasca Valles are perhaps the youngest outflow channel system on Mars. They lie 620 miles southeast of the large volcano Elysium Mons. Athabasca was formed by water that burst out of the Cerberus Fossae, a set of cracks or fissures in the ground. [35] [36] The Cerberus Fossae most likely were formed from the stress on the crust caused by the weight of both Elysium Mons and the Tharsis volcanoes. Current evidence suggests that Cerberus floods probably erupted in several stages. [37] Near the start of these channels (at one of the Cerberus Fossae), the system is called the Athabasca Valles; to the south and east it is called Marte Vallis. Flow rates in Marte Vallis have been estimated at around 100 times that of the Mississippi River. Eventually, the system just seems to fade out in the plains of Amazonis Planitia. [38]
Vallis or valles is the Latin word for valley. It is used in planetary geology to name landform features on other planets.
In planetary nomenclature, a fossa is a long, narrow depression (trough) on the surface of an extraterrestrial body, such as a planet or moon. The term, which means "ditch" or "trench" in Latin, is not a geological term as such but a descriptor term used by the United States Geological Survey (USGS) and the International Astronomical Union (IAU) for topographic features whose geology or geomorphology is uncertain due to lack of data or knowledge of the exact processes that formed them. Fossae are believed to be the result of a number of geological processes, such as faulting or subsidence. Many fossae on Mars are probably graben.
Cerberus is a large "dark spot" located on Mars and named after the mythical dog Cerberus. The arcuate (curved) markings in the upper right are in the Amazonis plains and may be sand drifts. The volcano Elysium Mons, a yellow area north of Cerberus, has several channels radiating from its flanks. The three bright spots, upper left, are volcanoes partially veiled by thin clouds.
Elysium, located in the Elysium and Cebrenia quadrangles, is the second largest volcanic region on Mars, after Tharsis. The region includes the volcanoes Hecates Tholus, Elysium Mons and Albor Tholus. The province is centered roughly on Elysium Mons at 24.7°N 150°E. Elysium Planitia is a broad plain to the south of Elysium, centered at 3.0°N 154.7°E. Another large volcano, Apollinaris Mons, lies south of Elysium Planitia and is not part of the province. Besides having large volcanoes, Elysium has several areas with long trenches, called fossa or fossae (plural) on Mars. They include the Cerberus Fossae, Elysium Fossae, Galaxias Fossae, Hephaestus Fossae, Hyblaeus Fossae, Stygis Fossae and Zephyrus Fossae.
The Memnonia quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Memnonia quadrangle is also referred to as MC-16.
Tempe Terra is a heavily cratered highland region in the northern hemisphere of the planet Mars. Located at the northeastern edge of the Tharsis volcanic province, Tempe Terra is notable for its high degree of crustal fracturing and deformation. The region also contains many small shield volcanoes, lava flows, and other volcanic structures.
The Cerberus Fossae are a series of semi-parallel fissures on Mars formed by faults which pulled the crust apart in the Cerberus region. They are 1235 km across and centered at 11.28 °N and 166.37 °E. Their northernmost latitude is 16.16 °N and their southernmost latitude 6.23 °N. Their easternmost and westernmost longitudes are 174.72 °E and 154.43 °E, respectively. They can be seen in the Elysium quadrangle.
The Athabasca Valles are a late Amazonian-period outflow channel system in the central Elysium Planitia region of Mars, located to the south of the Elysium Rise. They are part of a network of outflow channels in this region that are understood to emanate from large fissures in the Martian surface rather than the chaos terrains that source the circum-Chryse outflow channels. The Athabasca Valles in particular emanate from one of the Cerberus Fossae fissures and flow downstream to the southwest, constrained to the south by a wrinkle ridge for over 100 km, before debouching into the Cerberus Palus volcanic plain. The Athabasca Valles are widely understood to be the youngest outflow channel system on the planet.
The Cebrenia quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The quadrangle is located in the northeastern portion of Mars' eastern hemisphere and covers 120° to 180° east longitude and 30° to 65° north latitude. The quadrangle uses a Lambert conformal conic projection at a nominal scale of 1:5,000,000 (1:5M). The Cebrenia quadrangle is also referred to as MC-7. It includes part of Utopia Planitia and Arcadia Planitia. The southern and northern borders of the Cebrenia quadrangle are approximately 3,065 km (1,905 mi) and 1,500 km (930 mi) wide, respectively. The north to south distance is about 2,050 km (1,270 mi). The quadrangle covers an approximate area of 4.9 million square km, or a little over 3% of Mars' surface area.
The Arcadia quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The quadrangle is located in the north-central portion of Mars’ western hemisphere and covers 240° to 300° east longitude and 30° to 65° north latitude. The quadrangle uses a Lambert conformal conic projection at a nominal scale of 1:5,000,000 (1:5M). The Arcadia quadrangle is also referred to as MC-3. The name comes from a mountainous region in southern Greece. It was adopted by IAU, in 1958.
The Amenthes quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Amenthes quadrangle is also referred to as MC-14. The quadrangle covers the area from 225° to 270° west longitude and from 0° to 30° north latitude on Mars. Amenthes quadrangle contains parts of Utopia Planitia, Isidis Planitia, Terra Cimmeria, and Tyrrhena Terra.
The Amazonis quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Amazonis quadrangle is also referred to as MC-8.
The Iapygia quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Iapygia quadrangle is also referred to as MC-21. It was named after the heel of the boot of Italy. That name was given by the Greeks It is part of a region of Italy named Apulia. The name Iapygia was approved in 1958.
The Mare Tyrrhenum quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. This quadrangle is also referred to as MC-22. It contains parts of the regions Tyrrhena Terra, Hesperia Planum, and Terra Cimmeria.
The Phoenicis Lacus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Phoenicis Lacus quadrangle is also referred to as MC-17. Parts of Daedalia Planum, Sinai Planum, and Solis Planum are found in this quadrangle. Phoenicis Lacus is named after the phoenix which according to myth burns itself up every 500 years and then is reborn.
The Ceraunius Fossae are a set of fractures in the northern Tharsis region of Mars. They lie directly south of the large volcano Alba Mons and consist of numerous parallel faults and tension cracks that deform the ancient highland crust. In places, younger lava flows cover the fractured terrain, dividing it into several large patches or islands. They are found in the Tharsis quadrangle.
Outflow channels are extremely long, wide swathes of scoured ground on Mars. They extend many hundreds of kilometers in length and are typically greater than one kilometer in width. They are thought to have been carved by huge outburst floods.
HiWish is a program created by NASA so that anyone can suggest a place for the HiRISE camera on the Mars Reconnaissance Orbiter to photograph. It was started in January 2010. In the first few months of the program 3000 people signed up to use HiRISE. The first images were released in April 2010. Over 12,000 suggestions were made by the public; suggestions were made for targets in each of the 30 quadrangles of Mars. Selected images released were used for three talks at the 16th Annual International Mars Society Convention. Below are some of the over 4,224 images that have been released from the HiWish program as of March 2016.
Elysium Planitia, located in the Elysium and Aeolis quadrangles, is a broad plain that straddles the equator of Mars, centered at 3.0°N 154.7°E. It lies to the south of the volcanic province of Elysium, the second largest volcanic region on the planet, after Tharsis. Elysium contains the major volcanoes Elysium Mons, Albor Tholus and Hecates Tholus. Another more ancient shield volcano, Apollinaris Mons, is situated just to the south of eastern Elysium Planitia. Within the plains, Cerberus Fossae is the only Mars location with recent volcanic eruptions. Lava flows dated no older than 0.2 million years from the present have been found, and evidence has been found that volcanic activity may have occurred as recently as 53,000 years ago. Such activity could have provided the environment, in terms of energy and chemicals, needed to support life forms.
In summer 1965, the first close-up images from Mars showed a cratered desert with no signs of water. However, over the decades, as more parts of the planet were imaged with better cameras on more sophisticated satellites, Mars showed evidence of past river valleys, lakes and present ice in glaciers and in the ground. It was discovered that the climate of Mars displays huge changes over geologic time because its axis is not stabilized by a large moon, as Earth's is. Also, some researchers maintain that surface liquid water could have existed for periods of time due to geothermal effects, chemical composition, or asteroid impacts. This article describes some of the places that could have held large lakes.