Syrtis Major quadrangle
Encyclopedia
The Syrtis Major quadrangle
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 Syrtis Major quadrangle is also referred to as MC-13 (Mars Chart-13).

The quadrangle covers longitudes 270° to 315° west and latitudes 0° to 30° north 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...

.

Syrtis Major is an old shield volcano with a central depression that is elongated in a north-south direction. It contains the calderas Meroe Patera and Nili Patera.

Discovery and name

The name Syrtis Major is derived from the classical Roman
Ancient Rome
Ancient Rome was a thriving civilization that grew on the Italian Peninsula as early as the 8th century BC. Located along the Mediterranean Sea and centered on the city of Rome, it expanded to one of the largest empires in the ancient world....

 name Syrtis maior for the Gulf of Sidra
Gulf of Sidra
Gulf of Sidra is a body of water in the Mediterranean Sea on the northern coast of Libya; it is also known as Gulf of Sirte or the Great Sirte or Greater Syrtis .- Geography :The Gulf of Sidra has been a major centre for tuna fishing in the Mediterranean for centuries...

 on the coast of Libya
Libya
Libya is an African country in the Maghreb region of North Africa bordered by the Mediterranean Sea to the north, Egypt to the east, Sudan to the southeast, Chad and Niger to the south, and Algeria and Tunisia to the west....

 (classical Cyrenaica
Cyrenaica
Cyrenaica is the eastern coastal region of Libya.Also known as Pentapolis in antiquity, it was part of the Creta et Cyrenaica province during the Roman period, later divided in Libia Pentapolis and Libia Sicca...

).

Syrtis Major was the first documented surface feature of another planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...

. It was discovered by Christiaan Huygens, who included it in a drawing of Mars in 1659. The feature was originally known as the Hourglass Sea but has been given different names by different cartographers. In 1840, Johann Heinrich von Mädler
Johann Heinrich von Mädler
Johann Heinrich von Mädler was a German astronomer.He was orphaned at age 19 by an outbreak of typhus, and found himself responsible for raising three younger sisters...

 compiled a map of Mars from his observations and called the feature Atlantic Canale. In Richard Proctor's 1867 map it is called then Kaiser Sea (after Frederik Kaiser
Frederik Kaiser
Frederik Kaiser was a Dutch astronomer.He was director of the Leiden Observatory from 1838 until his death....

 of the Leiden Observatory
Leiden Observatory
Leiden Observatory is an astronomical observatory in the city of Leiden, Netherlands. It was established by Leiden University in 1633, to house the quadrant of Snellius, and is the oldest operating University observatory in the world Leiden Observatory (Sterrewacht Leiden in Dutch) is an...

). Camille Flammarion
Camille Flammarion
Nicolas Camille Flammarion was a French astronomer and author. He was a prolific author of more than fifty titles, including popular science works about astronomy, several notable early science fiction novels, and several works about Spiritism and related topics. He also published the magazine...

 called it the Mer du Sablier (French for "Hourglass Sea") when he revised Proctor's nomenclature in 1876. The name "Syrtis Major" was chosen by Giovanni Schiaparelli
Giovanni Schiaparelli
Giovanni Virginio Schiaparelli was an Italian astronomer and science historian. He studied at the University of Turin and Berlin Observatory. In 1859-1860 he worked in Pulkovo Observatory and then worked for over forty years at Brera Observatory...

 when he created a map based on observations made during Mars' close approach to Earth in 1877.

Igneous Rocks

Syrtis Major is of great interest to geologists because several types of igneous rocks have been found there with orbiting spacecraft. Besides 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...

, dacite
Dacite
Dacite is an igneous, volcanic rock. It has an aphanitic to porphyritic texture and is intermediate in composition between andesite and rhyolite. The relative proportions of feldspars and quartz in dacite, and in many other volcanic rocks, are illustrated in the QAPF diagram...

 and granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

 have been found there. Dacite originates under volcanoes in magma
Magma
Magma is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and dissolved gas and sometimes also gas bubbles. Magma often collects in...

 chambers. Dacites form at the top of the chamber, after heavy minerals (olivine
Olivine
The mineral olivine is a magnesium iron silicate with the formula 2SiO4. It is a common mineral in the Earth's subsurface but weathers quickly on the surface....

 and pyroxene
Pyroxene
The pyroxenes are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. They share a common structure consisting of single chains of silica tetrahedra and they crystallize in the monoclinic and orthorhombic systems...

) containing iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 and magnesium
Magnesium
Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...

 have settled to the bottom. Granite is formed by an even more complex process.

Some areas of Syrtis Major contain large amounts of the mineral olivine
Olivine
The mineral olivine is a magnesium iron silicate with the formula 2SiO4. It is a common mineral in the Earth's subsurface but weathers quickly on the surface....

. Olivine turns into other minerals very rapidly in the presence of water, so a high abundance of olivine suggests that for a long time little water has been there.

Minerals

A variety of important minerals have been discovered near Nili Fossae
Nili Fossae
Nili Fossae is a fracture in the surface of Mars that has been eroded and partly filled in by sediments and clay-rich ejecta from a nearby crater. It is located at approximately 22°N, 75°E, and has an elevation of...

, a major trough system in Syrtis major. Besides a large exposure of olivine
Olivine
The mineral olivine is a magnesium iron silicate with the formula 2SiO4. It is a common mineral in the Earth's subsurface but weathers quickly on the surface....

 located in Nili Fossae. Other minerals found there include carbonates, aluminum smectite, iron/magnesium smecite, hydrated silica, kaolinite group minerals, and iron oxides. In December 2008, NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

's Mars Reconnaissance Orbiter
Mars Reconnaissance Orbiter
Mars Reconnaissance Orbiter is a NASA multipurpose spacecraft designed to conduct reconnaissance and Exploration of Mars from orbit...

 found that rocks at Nili Fossae contain carbonate minerals
Carbonate minerals
Carbonate minerals are those minerals containing the carbonate ion: CO32-.-Anhydrous carbonates:*Calcite group: Trigonal**Calcite CaCO3**Gaspeite CO3**Magnesite MgCO3**Otavite CdCO3**Rhodochrosite MnCO3**Siderite FeCO3**Smithsonite ZnCO3...

, a geologically significant discovery. Later research published in October 2010, described a large deposit of carbonate rocks found inside Leighton Crater at a level that was once buried 4 miles (6 km) below the surface. Finding carbonates in an underground location strongly suggests that Mars was warmer and had more atmospheric carbon dioxide and ancient seas. Because the carbonates were near silicate minerals and clays hydrothermal systems like the deep sea vents on Earth may have been present.

Other minerals found by MRO
MRO
-Operations:* maintenance, repair, and operations -Companies:...

 are aluminum smectite, iron/magnesium smecite, hydrated silica, kaolinite group minerals, iron oxides, and talc.
NASA scientists discovered that Nili Fossae is the source of plumes of methane, raising the question of whether this source originates from biological sources.

Research, published in the fall of 2010, describes the discovery of hydrated silica on the flanks of a volcanic cone. The deposit was from a steam fumarole
Fumarole
A fumarole is an opening in a planet's crust, often in the neighborhood of volcanoes, which emits steam and gases such as carbon dioxide, sulfur dioxide, hydrochloric acid, and hydrogen sulfide. The steam is created when superheated water turns to steam as its pressure drops when it emerges from...

 or hot spring, and it represents a recent habitable microenvironment. The 100 meter high cone rests on the floor of Nili Patera. Observations were obtained with NASA's Mars Reconnaissance Orbiter
Mars Reconnaissance Orbiter
Mars Reconnaissance Orbiter is a NASA multipurpose spacecraft designed to conduct reconnaissance and Exploration of Mars from orbit...

.

Dikes

Narrow ridges occur in some places on Mars. They may be formed by different means, but some are probably caused by molten rock moving underground, cooling into hard rock, then being exposed by the erosion of softer, surrounding materials. Such a feature is termed a dike. They are common on Earth—some famous ones are Shiprock
Shiprock
Shiprock is a rock formation rising nearly above the high-desert plain on the Navajo Nation in San Juan County, New Mexico, USA. It has a peak elevation of above the sea level. It lies about southwest of the town of Shiprock, which is named for the peak...

, New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...

; around Spanish Peaks
Spanish Peaks
The Spanish Peaks are a pair of volcanic mountains located in southwestern Huerfano County, Colorado. The Ute indians named them Huajatolla , meaning "two breasts". The Spanish name translates as "Breasts of the Earth". The two peaks, West Spanish Peak and East Spanish Peak, are the easternmost...

, Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...

; and the "Iron Dike" in Rocky Mountain National Park
Rocky Mountain National Park
Rocky Mountain National Park is a national park located in the north-central region of the U.S. state of Colorado.It features majestic mountain views, a variety of wildlife, varied climates and environments—from wooded forests to mountain tundra—and easy access to back-country trails...

, Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...

.
The discovery on Mars of dikes that were formed from molten rock is highly significant because dikes indicate the existence of intrusive igneous activity. On the Earth such activity is associated with precious metals like gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...

, silver
Silver
Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...

, and tellurium. Dikes and other intrusive structures are common in the Cripple Creek Mining District of Colorado; the Battle Mountain-Eureka area in north-central Nevada, famous for gold and molybdenum
Molybdenum
Molybdenum , is a Group 6 chemical element with the symbol Mo and atomic number 42. The name is from Neo-Latin Molybdaenum, from Ancient Greek , meaning lead, itself proposed as a loanword from Anatolian Luvian and Lydian languages, since its ores were confused with lead ores...

 deposits; and around the Franklin dike swarm
Franklin dike swarm
The Franklin dike swarm, also called the Franklin dikes, is a Proterozoic dike swarm of the Franklin Large Igneous Province in Northern Canada. It is one of the several major magmatic events in the Canadian Shield and it was formed 723 million years ago...

 in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

.
Mapping the presence of dikes allows us to understand how magma
Magma
Magma is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and dissolved gas and sometimes also gas bubbles. Magma often collects in...

 (molten rock under the ground) travels and where it could have interacted with surrounding rock, thus producing valuable ores
Orés
Orés is a municipality in the Cinco Villas, in the province of Zaragoza, in the autonomous community of Aragon, Spain. It belongs to the comarca of Cinco Villas. It is placed 104 km to the northwest of the provincial capital city, Zaragoza. Its coordinates are: 42° 17' N, 1° 00' W, and is...

. Deposits of important minerals are also made by dikes and other igneous intrusion
Intrusion
An intrusion is liquid rock that forms under Earth's surface. Magma from under the surface is slowly pushed up from deep within the earth into any cracks or spaces it can find, sometimes pushing existing country rock out of the way, a process that can take millions of years. As the rock slowly...

s heating water which then dissolves minerals that are deposited in cracks in nearby rock. One would expect a great deal of intrusive igneous activity to occur on Mars because it is believed there is more igneous activity under the ground than on top, and Mars has many huge volcanoes.
Some crater floors in the Syrtis Major area show elongated ridges in a lattice-like pattern. Such patterns are typical of faults and breccia dikes
Dike (geology)
A dike or dyke in geology is a type of sheet intrusion referring to any geologic body that cuts discordantly across* planar wall rock structures, such as bedding or foliation...

 formed as a result of an impact. The ridges are found where there has been enhanced erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

. Pictures below show examples of these dikes. Water may flow along faults. The water often carries minerals that serve to cement rock materials thus making them harder. Later when the whole area undergoes erosion the dikes will remain as ridges because they are more resistant to erosion. This discovery may be of great importance for future colonization of Mars because these types of faults and breccia dikes on earth are associated with key mineral resources. It has been estimated that 25% of the Earth's impacts are connected to mineral production. The largest gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...

 deposit on Earth is the Vredefort
Vredefort
Vredefort is a small farming town in the Free State province of South Africa with cattle, peanuts, sorghum, sunflowers and maize being farmed. It is home to 3,000 residents....

 300 km diameter impact structure in South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

. Perhaps, when people live on Mars these kinds of areas will be mined as they are on earth.

Buttes

Many places on Mars have buttes that are similar to buttes on Earth, such as the famous ones in Monument Valley
Monument Valley
Monument Valley is a region of the Colorado Plateau characterized by a cluster of vast sandstone buttes, the largest reaching above the valley floor. It is located on the northern border of Arizona with southern Utah , near the Four Corners area...

, Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...

. Buttes are formed when most of a layer(s) of rocks are removed from an area. Buttes usually have a hard, erosion resistant cap rock on the top. The cap rock causes the top of a butte to be flat. An example of a butte in the Syrtis Major quadrangle is shown below.

Dunes

Sand dunes are found all over Mars. Often sand dunes will form in low areas, for example on the floor of ancient river valleys. Dunes on the floor of Arnus Vallis
Arnus Vallis
Arnus Vallis is an ancient river valley in the Syrtis Major quadrangle of Mars, located at 14.1° north latitude and 289.5° west longitude. It is 280 km long and was named after the classical and present day Arno River in Tuscany, Italy .Arnus Vallis is an ancient river valley in the Syrtis...

, an old river valley are visible in a picture below. Dunes in valleys on Mars usually lie at right angles to the valley walls.

Streaks

Many areas of Mars change their shape and/or coloration. For many years, astronomers observing regular changes on Mars when the seasons changed, thought that what they saw was evidence of vegetation growing. After close-up inspection with a number of spacecraft, other causes were discovered. Basically, the changes are caused by the effects of the wind blowing dust around. Sometimes, fine bright dust settles on the dark basalt rock making the surface appear lighter, at other times the light-toned dust will be blown away; thus making the surface darken—just as if vegetation were growing. Mars has frequent regional or global dust storms that coat the surface with fine bright dust. In the THEMIS
Themis
Themis is an ancient Greek Titaness. She is described as "of good counsel", and is the embodiment of divine order, law, and custom. Themis means "divine law" rather than human ordinance, literally "that which is put in place", from the verb τίθημι, títhēmi, "to put"...

 image below, white streaks are seen downwind of craters. The streaks are not too bright; they appear bright because of contrast with the dark volcanic rock 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...

 which makes up the surface.

Inverted Relief

Some places on Mars show inverted relief. In these locations, a stream bed may be a raised feature, instead of a valley. The inverted former stream channels may be caused by the deposition of large rocks or due to cementation. In either case erosion would erode the surrounding land and leave the old channel as a raised ridge because the ridge would be more resistant to erosion. Images below, taken with 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....

 show sinuous ridges that are old channels that have become inverted.

Methane

For several years, researchers have found methane in the atmosphere of Mars. After study, it was determined to be coming from a point in Syrtis Major, located at 10° N and 50° E.
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 one location. 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.

See also

  • Water on Mars
    Water on Mars
    Water 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 Mars
    Geology of Mars
    The 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...

  • Inverted Relief
    Inverted Relief
    Inverted relief is a landscape that is part of a planet's surface, e.g. Mars, that contains positive landforms, i.e. hills and ridges, that were once depressions in its surface...

  • Vallis
    Vallis
    Vallis is the Latin word for valley. It is used in planetary geology for the naming of landform features on other planets....

  • Vredefort crater
    Vredefort crater
    Vredefort crater is the largest verified impact crater on Earth. It is located in the Free State Province of South Africa and named after the town of Vredefort, which is situated near its centre. The site is also known as the Vredefort dome or Vredefort impact structure...

  • Ore genesis
    Ore genesis
    The various theories of ore genesis explain how the various types of mineral deposits form within the Earth's crust. Ore genesis theories are very dependent on the mineral or commodity....

  • hydrothermal circulation
    Hydrothermal circulation
    Hydrothermal circulation in its most general sense is the circulation of hot water; 'hydros' in the Greek meaning water and 'thermos' meaning heat. Hydrothermal circulation occurs most often in the vicinity of sources of heat within the Earth's crust...

  • Igneous differentiation
    Igneous differentiation
    In geology, igneous differentiation is an umbrella term for the various processes by which magmas undergo bulk chemical change during the partial melting process, cooling, emplacement or eruption.-Primary melts:...

  • Dike (geology)
    Dike (geology)
    A dike or dyke in geology is a type of sheet intrusion referring to any geologic body that cuts discordantly across* planar wall rock structures, such as bedding or foliation...

  • Ore resources on Mars
    Ore resources on Mars
    Mars may contain valuable ores that will be very useful to future colonists. The abundance of volcanic features together with widespread cratering are strong evidence for a variety of ores.- How deposits are made :...

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