Elysium quadrangle
Encyclopedia
Quadrangle (geography)
In geology or geography, the word "quadrangle" usually refers to a United States Geological Survey 7.5-minute quadrangle map, which are usually named after a local physiographic feature. The shorthand "quad" is also used, especially with the name of the map; for example, "the Ranger Creek, Texas...
is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey
United States Geological Survey
The United States Geological Survey is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization has four major science disciplines, concerning biology,...
(USGS) Astrogeology Research Program
Astrogeology Research Program
The USGS Astrogeology Science Center has a rich history of participation in space exploration efforts and planetary mapping, starting in 1963 when the Flagstaff Science Center was established by Gene Shoemaker to provide lunar geologic mapping and assist in training astronauts destined for the...
. The Elysium quadrangle is also referred to as MC-15 (Mars Chart-15).
The Elysium quadrangle covers the area 180° to 225° west longitude and 0° to 30° north latitude on Mars
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
.
Volcanoes
The Elysium quadrangle contains the volcanoes Elysium Mons and Albor Tholus. Much of this area 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. 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
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
, that "was put in place turbulently over the span of several weeks at most." This flow, near Athabasca Valles
Athabasca Valles
Athabasca Valles is an outflow channel on Mars, cut into its surface by catastrophic flooding. It is one of the youngest known of these structures, probably forming only in the geologically recent past of Mars. The flood produced distinctive "teardrop" landforms similar to those found in the...
, is the youngest lava flow on Mars. It is thought to be of Late Amazonian Age.
Layers
Elysium Fossae contains 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 RoverMars Rover
A Mars rover is an automated motor vehicle which propels itself across the surface of the planet Mars after landing.Rovers have several advantages over stationary landers: they examine more territory, they can be directed to interesting features, they can place themselves in sunny positions to...
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
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
, 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. Places that contain clays and/or other hydrated minerals would be good places to look for evidence of life.
Rock can be formed into layers in a variety of ways. Volcanoes, wind, or water can produce layers.
Fossa/pit craters
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. 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. Lake GeorgeLake George (New York)
Lake George, nicknamed the Queen of American Lakes, is a long, narrow oligotrophic lake draining northwards into Lake Champlain and the St. Lawrence River Drainage basin located at the southeast base of the Adirondack Mountains in northern New York, U.S.A.. It lies within the upper region of the...
, 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, 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. 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. The images below of Cerberus Fossae
Cerberus Fossae
The Cerberus Fossae are a series of semi-parallel fissures on Mars formed by faults which pulled the crust apart in the Cerberus region . Ripples seen at the bottom of the fault are sand blown by the wind ....
, Elysium Fossae
Elysium Fossae
Elysium Fossae is a large trough in the Elysium quadrangle of Mars at 24.8° north latitude and 213.7° west longitude. It is about 1,175 km long and is named after a classical albedo feature name.- Layers :...
and other troughs, as seen by HiRISE
HiRISE
High Resolution Imaging Science Experiment is a camera on board the Mars Reconnaissance Orbiter. The 65 kg , $40 million instrument was built under the direction of the University of Arizona's Lunar and Planetary Laboratory by Ball Aerospace & Technologies Corp....
are examples of fossa.
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.
Methane
MethaneMethane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...
has been detected in three areas on Mars; one of which is in the Elysium quadrangle.
This is exciting because one possible source of methane is from the metabolism of living bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
. 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 atmospehre 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.
Craters
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. The peak is caused by a rebound of the crater floor following the impact. 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.Vallis in the Elysium quadrangle
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 gread deal of ice. Two valleys, Hephaestus Fossae and Hebrus Valles, have sections that join and branch at high angles.Perhaps the youngest outflow channel on Mars is Athabasca Valles
Athabasca Valles
Athabasca Valles is an outflow channel on Mars, cut into its surface by catastrophic flooding. It is one of the youngest known of these structures, probably forming only in the geologically recent past of Mars. The flood produced distinctive "teardrop" landforms similar to those found in the...
. It lies 620 miles southeast of the large volcano Elysium Mons
Elysium Mons
Elysium Mons is a volcano on Mars located in the Elysium Planitia, at , in the Martian eastern hemisphere. It stands about 13.9 km above the surrounding lava plains, and about 16 km above the Martian datum. Its diameter is about 240 km, with a summit caldera about 14 km across...
. Athabasca was formed by water that burst out of Cerberus Fossae
Cerberus Fossae
The Cerberus Fossae are a series of semi-parallel fissures on Mars formed by faults which pulled the crust apart in the Cerberus region . Ripples seen at the bottom of the fault are sand blown by the wind ....
, a set of cracks or fissures in the ground. Cerberus Fossae
Cerberus Fossae
The Cerberus Fossae are a series of semi-parallel fissures on Mars formed by faults which pulled the crust apart in the Cerberus region . Ripples seen at the bottom of the fault are sand blown by the wind ....
most likely was formed from the stress on the crust caused by the weight of both Elysium Mons and Tharsis volcanoes. Current evidence suggests that Cerberus floods probably erupted in several stages. Near the start of these channels (Cerberus Fossae), the system is called 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.
See also
- Climate of MarsClimate of MarsThe climate of Mars has been an issue of scientific curiosity for centuries, not least because Mars is the only terrestrial planet whose surface can be directly observed in detail from the Earth....
- Water on MarsWater on MarsWater on Mars is a psychedelic rock and electronic music group from Quebec City, Québec, Canada. The music trio is led by Philippe Navarro, guitarist, vocalist, arranger, producer, principal lyricist, and music composer....
- Geology of MarsGeology of MarsThe geology of Mars is the scientific study of the surface, crust, and interior of the planet Mars. It emphasizes the composition, structure, history, and physical processes that shape the planet. It is fully analogous to the field of terrestrial geology. In planetary science, the term geology is...
- Impact craterImpact craterIn the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
- VallisVallisVallis is the Latin word for valley. It is used in planetary geology for the naming of landform features on other planets....
- Fossa (geology)Fossa (geology)Fossa is a term used in planetary geology to describe a long, narrow depression on the surface of an extraterrestrial body, such as a planet or moon...