The Geology Portal
Geology (from Ancient Greek γῆ (gê) 'earth' and λoγία (-logía) 'study of, discourse') is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology. It is integrated with Earth system science and planetary science.
Geology describes the structure of the Earth on and beneath its surface and the processes that have shaped that structure. Geologists study the mineralogical composition of rocks in order to get insight into their history of formation. Geology determines the relative ages of rocks found at a given location; geochemistry (a branch of geology) determines their absolute ages. By combining various petrological, crystallographic, and paleontological tools, geologists are able to chronicle the geological history of the Earth as a whole. One aspect is to demonstrate the age of the Earth. Geology provides evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates.
Geologists broadly study the properties and processes of Earth and other terrestrial planets. Geologists use a wide variety of methods to understand the Earth's structure and evolution, including fieldwork, rock description, geophysical techniques, chemical analysis, physical experiments, and numerical modelling. In practical terms, geology is important for mineral and hydrocarbon exploration and exploitation, evaluating water resources, understanding natural hazards, remediating environmental problems, and providing insights into past climate change. Geology is a major academic discipline, and it is central to geological engineering and plays an important role in geotechnical engineering. (Full article...)
Recognized content -
Entries here consist of Good and Featured articles, which meet a core set of high editorial standards.
-
The 1867 Manhattan earthquake struck Riley County, Kansas, in the United States on April 24, 1867, at 20:22 UTC, or about 14:30 local time. The strongest earthquake to originate in the state, it measured 5.1 on a seismic scale that is based on an isoseismal map or the event's felt area. The earthquake's epicenter was near the town of Manhattan.
The earthquake had a maximum perceived intensity of VII (Very strong) on the Mercalli intensity scale. It caused minor damage, reports of which were confined to Kansas, Iowa, and Missouri, according to the United States Geological Survey. Felt over an area of 200,000 square miles (520,000 km2), the earthquake reached the states of Indiana, Illinois, and possibly Ohio, though the latter reports have been questioned. (Full article...) -
The ACFEL ice auger showing an ice core pushed up into the core remover barrel.
Ice drilling allows scientists studying glaciers and ice sheets to gain access to what is beneath the ice, to take measurements along the interior of the ice, and to retrieve samples. Instruments can be placed in the drilled holes to record temperature, pressure, speed, direction of movement, and for other scientific research, such as neutrino detection.
Many different methods have been used since 1840, when the first scientific ice drilling expedition attempted to drill through the Unteraargletscher in the Alps. Two early methods were percussion, in which the ice is fractured and pulverized, and rotary drilling, a method often used in mineral exploration for rock drilling. In the 1940s, thermal drills began to be used; these drills melt the ice by heating the drill. Drills that use jets of hot water or steam to bore through ice soon followed. A growing interest in ice cores, used for palaeoclimatological research, led to ice coring drills being developed in the 1950s and 1960s, and there are now many different coring drills in use. For obtaining ice cores from deep holes, most investigators use cable-suspended electromechanical drills, which use an armoured cable to carry electrical power to a mechanical drill at the bottom of the borehole. (Full article...) -
David Alexander Johnston (December 18, 1949 – May 18, 1980) was an American United States Geological Survey (USGS) volcanologist who was killed by the 1980 eruption of Mount St. Helens in the U.S. state of Washington. A principal scientist on the USGS monitoring team, Johnston was killed in the eruption while manning an observation post six miles (10 km) away on the morning of May 18, 1980. He was the first to report the eruption, transmitting "Vancouver! Vancouver! This is it!" before he was swept away by a lateral blast; despite a thorough search, Johnston's body was never found, but state highway workers discovered remnants of his USGS trailer in 1993.
Johnston's career took him across the United States, where he studied the Augustine Volcano in Alaska, the San Juan volcanic field in Colorado, and long-extinct volcanoes in Michigan. Johnston was a meticulous and talented scientist, known for his analyses of volcanic gases and their relationship to eruptions. This, along with his enthusiasm and positive attitude, made him liked and respected by many co-workers. After his death, other scientists lauded his character, both verbally and in dedications and letters. Johnston felt scientists must do what is necessary, including taking risks, to help protect the public from natural disasters. His work, and that of fellow USGS scientists, convinced authorities to close Mount St. Helens to the public before the 1980 eruption. They maintained the closure despite heavy pressure to re-open the area; their work saved thousands of lives. His story became intertwined with the popular image of volcanic eruptions and their threat to society, and a part of volcanology's history. To date, Johnston, along with his mentee Harry Glicken, is one of two American volcanologists known to have died in a volcanic eruption. (Full article...) -
The Grand Canyon from Navajo Point. The Colorado River is to the right and the North Rim is visible at all in the distance. The view shows nearly every sedimentary layer described in this article.
The geology of the Grand Canyon area includes one of the most complete and studied sequences of rock on Earth. The nearly 40 major sedimentary rock layers exposed in the Grand Canyon and in the Grand Canyon National Park area range in age from about 200 million to nearly 2 billion years old. Most were deposited in warm, shallow seas and near ancient, long-gone sea shores in western North America. Both marine and terrestrial sediments are represented, including lithified sand dunes from an extinct desert. There are at least 14 known unconformities in the geologic record found in the Grand Canyon.
Uplift of the region started about 75 million years ago during the Laramide orogeny; a mountain-building event that is largely responsible for creating the Rocky Mountains to the east. In total, the Colorado Plateau was uplifted an estimated 2 miles (3.2 km). The adjacent Basin and Range Province to the west started to form about 18 million years ago as the result of crustal stretching. A drainage system that flowed through what is today the eastern Grand Canyon emptied into the now lower Basin and Range province. The opening of the Gulf of California around 6 million years ago enabled a large river to cut its way northeast from the gulf. The new river captured the older drainage to form the ancestral Colorado River, which in turn started to form the Grand Canyon. (Full article...) -
The Mono–Inyo Craters are a volcanic chain of craters, domes and lava flows in Mono County, Eastern California. The chain stretches 25 miles (40 km) from the northwest shore of Mono Lake to the south of Mammoth Mountain. The Mono Lake Volcanic Field forms the northernmost part of the chain and consists of two volcanic islands in the lake and one cinder cone volcano on its northwest shore. Most of the Mono Craters, which make up the bulk of the northern part of the Mono–Inyo chain, are phreatic (steam explosion) volcanoes that have since been either plugged or over-topped by rhyolite domes and lava flows. The Inyo volcanic chain form much of the southern part of the chain and consist of phreatic explosion pits, and rhyolitic lava flows and domes. The southernmost part of the chain consists of fumaroles and explosion pits on Mammoth Mountain and a set of cinder cones south of the mountain; the latter are called the Red Cones.
Eruptions along the narrow fissure system under the chain began in the west moat of Long Valley Caldera 400,000 to 60,000 years ago. Mammoth Mountain was formed during this period. Multiple eruptions from 40,000 to 600 years ago created the Mono Craters and eruptions 5,000 to 500 years ago formed the Inyo volcanic chain. Lava flows 5,000 years ago built the Red Cones, and explosion pits on Mammoth Mountain were excavated in the last 1,000 years. Uplift of Paoha Island in Mono Lake about 250 years ago is the most recent activity. These eruptions most likely originated from small magma bodies rather than from a single, large magma chamber like the one that produced the massive Long Valley Caldera eruption 760,000 years ago. During the past 3,000 years, eruptions have occurred every 250 to 700 years. In 1980, a series of earthquakes and uplift within and south of Long Valley Caldera indicated renewed activity in the area. (Full article...) -
Map of SSSIs in Cornwall within the UK
There are 167 Sites of Special Scientific Interest (SSSIs) in Cornwall (including the Isles of Scilly). Cornwall, in the south-west of England, UK, has a population of 575,413 (2022) across an area of 3,545 km2 (875,988.6 acres), making it one of the least densely populated counties within England. The north coast of Cornwall falls on the Celtic Sea in the Atlantic Ocean, which also surrounds the Isles of Scilly, the south coast falls on the English Channel and the county is bounded by the River Tamar, forming the border with Devon, to the east. Cornish geology consists mainly of rocks from the Devonian and Carboniferous geological periods. Granite forms a large part of these, with mineralisations of tin, copper, lead and arsenic having been mined in the area. This gives rise to many distinct habitats, with strong marine influences, including sand dunes, rocky reefs, stacks and headlands as well as heathland, moorland and unusual river profiles.
In England the body responsible for designating SSSIs is Natural England, which chooses a site "because of its flora, fauna, or geological or physiographical features". Natural England took over the role of designating and managing SSSIs from English Nature in October 2006 when it was formed from the amalgamation of English Nature, parts of the Countryside Agency and the Rural Development Service. Natural England, like its predecessor, uses the 1974–96 county system and as such the same approach is followed here, rather than adopting the current local government or ceremonial county boundaries. (Full article...) -
The Qayen earthquake, also known as the Ardekul or Qaen earthquake, struck northern Iran's Khorasan Province in the vicinity of Qaen on May 10, 1997, at 07:57 UTC (12:57 local time). The largest in the area since 1990, the earthquake registered 7.3 on the moment magnitude scale and was centered approximately 270 kilometers (170 mi) south of Mashhad on the village of Ardekul. The third earthquake that year to cause severe damage, it devastated the Birjand–Qayen region, killing 1,567 and injuring more than 2,300. The earthquake—which left 50,000 homeless and damaged or destroyed over 15,000 homes—was described as the deadliest of 1997 by the United States Geological Survey. Some 155 aftershocks caused further destruction and drove away survivors. The earthquake was later discovered to have been caused by a rupture along a fault that runs underneath the Iran–Afghanistan border.
Damage was eventually estimated at $100 million, and many countries responded to the emergency with donations of blankets, tents, clothing, and food. Rescue teams were also dispatched to assist local volunteers in finding survivors trapped under the debris. The destruction around the earthquake's epicenter was, in places, almost total; this has been attributed to poor construction practices in rural areas, and imparted momentum to a growing movement for changes in building codes for earthquake-safe buildings. With 1 in 3,000 deaths in Iran attributable to earthquakes, a US geophysicist has suggested that a country-wide rebuilding program would be needed to address the ongoing public safety concerns. (Full article...) -
Io, with two plumes erupting from its surface, Galileo image, June 1997
Volcanism on Io, a moon of Jupiter, is represented by the presence of volcanoes, volcanic pits and lava flows on the surface. Io's volcanic activity was discovered in 1979 by Linda Morabito, an imaging scientist working on Voyager 1. Observations of Io by passing spacecraft and Earth-based astronomers have revealed more than 150 active volcanoes. As of 2024[update], up to 400 such volcanoes are predicted to exist based on these observations. Io's volcanism makes the satellite one of only four known currently volcanically or cryovolcanically active worlds in the Solar System (the others being Earth, Saturn's moon Enceladus, and Neptune's moon Triton.)
First predicted shortly before the Voyager 1 flyby, the heat source for Io's volcanism comes from tidal heating produced by its forced orbital eccentricity. This differs from Earth's internal heating, which is derived primarily from radioactive isotope decay and primordial heat of accretion. Io's eccentric orbit leads to a slight difference in Jupiter's gravitational pull on the satellite between its closest and farthest points on its orbit, causing a varying tidal bulge. This variation in the shape of Io causes frictional heating in its interior. Without this tidal heating, Io might have been similar to the Moon, a world of similar size and mass, geologically dead and covered with numerous impact craters. (Full article...) -
The 1991 eruption of Mount Pinatubo, the largest eruption since 1912, is dwarfed by the eruptions in this list.
In a volcanic eruption, lava, volcanic bombs, ash, and various gases are expelled from a volcanic vent and fissure. While many eruptions only pose dangers to the immediately surrounding area, Earth's largest eruptions can have a major regional or even global impact, with some affecting the climate and contributing to mass extinctions. Volcanic eruptions can generally be characterized as either explosive eruptions, sudden ejections of rock and ash, or effusive eruptions, relatively gentle outpourings of lava. A separate list is given below for each type.
There have probably been many such eruptions during Earth's history beyond those shown in these lists. However erosion and plate tectonics have taken their toll, and many eruptions have not left enough evidence for geologists to establish their size. Even for the eruptions listed here, estimates of the volume erupted can be subject to considerable uncertainty. (Full article...) -
Cerro Azul (Spanish pronunciation: [ˈsero aˈsul], blue hill in Spanish), sometimes referred to as Quizapu, is an active stratovolcano in the Maule Region of central Chile, immediately south of Descabezado Grande. Part of the South Volcanic Zone of the Andes, its summit is 3,788 meters (12,428 ft) above sea level, and is capped by a summit crater that is 500 meters (1,600 ft) wide and opens to the north. Beneath the summit, the volcano features numerous scoria cones and flank vents.
Cerro Azul is responsible for several of South America's largest recorded eruptions, in 1846 and 1932. In 1846, an effusive eruption formed the vent at the site of present-day Quizapu crater on the northern flank of Cerro Azul and sent lava flowing down the sides of the volcano, creating a lava field 8–9 square kilometres (3–3.5 square miles) in area. Phreatic and Strombolian volcanism between 1907 and 1932 excavated this crater. In 1932, one of the largest explosive eruptions of the 20th century occurred at Quizapu Crater and sent 9.5 cubic kilometers (2.3 cu mi) of ash into the atmosphere. The volcano's most recent eruption was in 1967. (Full article...)
Vital article
Vital articles to understand Geology.
The geology of the Grand Canyon area includes one of the most complete and studied sequences of rock on Earth. The nearly 40 major sedimentary rock layers exposed in the Grand Canyon and in the Grand Canyon National Park area range in age from about 200 million to nearly 2 billion years old. Most were deposited in warm, shallow seas and near ancient, long-gone sea shores in western North America. Both marine and terrestrial sediments are represented, including lithified sand dunes from an extinct desert. There are at least 14 known unconformities in the geologic record found in the Grand Canyon. (Full article...)
Related portals
Get involved
For editor resources and to collaborate with other editors on improving Wikipedia's Geology-related articles, visit WikiProject Geology.
Featured biography
Featured biography articles in Geology
Ali Mehmet Celâl Şengör (Turkish: [ˈali ˈmehmet ˈdʒeɫal ˈʃænɟœɾ]; born 24 March 1955) is a Turkish geologist. He is retired from the faculty at Istanbul Technical University, Department of Geological Engineering.
Şengör is a (foreign) member of the American Philosophical Society, the United States National Academy of Sciences, the Russian Academy of Sciences and the Serbian Academy of Sciences and Arts. He is a foreign member of the Russian Academy of Science. He is a recipient of Gustav-Steinmann-Medaille — the highest distinction of the Geologische Vereinigung e.V. (Full article...)
Did you know
Did you know it about Geology?
- ... that the groundwater level of a coastal aquifer system changes with the tide?
- ... that from 1904 to 1911 Arthur Lewis Hall covered 17,479 miles (28,130 km), mostly on foot, to map the geology of the Transvaal?
- ... that the Apollo 12 Solar Wind Spectrometer detected a gas-ion shockwave produced by the impact of the Apollo 13 S-IVB stage on the lunar surface?
- ... that the Danish geologist Tove Birkelund received a gold medal for her early work on fossils of Scaphites in Greenland?
- ... that Frederick Murray Trotter had a distinguished career as a field geologist despite losing a part of his skull and an eye to shrapnel during World War I?
- ... that English amateur geologist Charlotte Eyton wrote a number of papers and pamphlets on the geology of the Wrekin, a part of Shropshire, between 1862 and 1870?
- ... that Karen Hanghøj, the 2023 winner of the William Smith Medal for applied geology, became the first female director of the British Geological Survey, 183 years after it was founded?
- ... that the geology of the Ellsworth Mountains was explored by geologists using motor toboggans in 1961?
Top 10 WikiProject Geology Popular articles of the month
This following Geology-related articles is a most visited articles of WikiProject Geology, See complete list at Wikipedia:WikiProject Geology/Popular pages.
-
Earth is the third planet from the Sun and the only astronomical object known to harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all of Earth's water is contained in its global ocean, covering 70.8% of Earth's crust. The remaining 29.2% of Earth's crust is land, most of which is located in the form of continental landmasses within Earth's land hemisphere. Most of Earth's land is somewhat humid and covered by vegetation, while large sheets of ice at Earth's polar deserts retain more water than Earth's groundwater, lakes, rivers and atmospheric water combined. Earth's crust consists of slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Earth has a liquid outer core that generates a magnetosphere capable of deflecting most of the destructive solar winds and cosmic radiation. (Full article...) -
Mount Everest, known locally as Sagarmatha or Qomolangma, is Earth's highest mountain above sea level, located in the Mahalangur Himal sub-range of the Himalayas. The China–Nepal border runs across its summit point. Its elevation (snow height) of 8,848.86 m (29,031 ft 8+1⁄2 in) was most recently established in 2020 by the Chinese and Nepali authorities. (Full article...) -
Animated, colour-coded map showing some continents and the region of Oceania (purple), which includes the continent of Australia. Depending on the convention and model, some continents may be consolidated or subdivided.
A continent is any of several large geographical regions. Continents are generally identified by convention rather than any strict criteria. A continent could be a single landmass or a part of a very large landmass, as in the case of Asia or Europe. Due to this, the number of continents varies; up to seven or as few as four geographical regions are commonly regarded as continents. Most English-speaking countries recognize seven regions as continents. In order from largest to smallest in area, these seven regions are Asia, Africa, North America, South America, Antarctica, Europe, and Australia. Different variations with fewer continents merge some of these regions; examples of this are merging North America and South America into America, Asia and Europe into Eurasia, and Africa, Asia, and Europe into Afro-Eurasia. (Full article...) -
The Chicxulub crater (IPA: [t͡ʃikʃuˈluɓ] cheek-shoo-LOOB) is an impact crater buried underneath the Yucatán Peninsula in Mexico. Its center is offshore, but the crater is named after the onshore community of Chicxulub Pueblo (not the larger coastal town of Chicxulub Puerto). It was formed slightly over 66 million years ago when an asteroid, about ten kilometers (six miles) in diameter, struck Earth. The crater is estimated to be 200 kilometers (120 miles) in diameter and 1 kilometer (0.62 miles) in depth. It is believed to be the second largest impact structure on Earth, and the only one whose peak ring is intact and directly accessible for scientific research. (Full article...) -
Charles Robert Darwin FRS FRGS FLS FZS JP (/ˈdɑːrwɪn/ DAR-win; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended from a common ancestor is now generally accepted and considered a fundamental scientific concept. In a joint publication with Alfred Russel Wallace, he introduced his scientific theory that this branching pattern of evolution resulted from a process he called natural selection, in which the struggle for existence has a similar effect to the artificial selection involved in selective breeding. Darwin has been described as one of the most influential figures in human history and was honoured by burial in Westminster Abbey. (Full article...) -
Changes in surface air temperature over the past 50 years. The Arctic has warmed the most, and temperatures on land have generally increased more than sea surface temperatures.
Present-day climate change includes both global warming—the ongoing increase in global average temperature—and its wider effects on Earth's climate. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global temperatures is driven by human activities, especially fossil fuel burning since the Industrial Revolution. Fossil fuel use, deforestation, and some agricultural and industrial practices release greenhouse gases. These gases absorb some of the heat that the Earth radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary greenhouse gas driving global warming, has grown by about 50% and is at levels unseen for millions of years. (Full article...) -
Gold is a chemical element with the chemical symbol Au (from Latin aurum) and atomic number 79. In its pure form, it is a bright, slightly orange-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal, a group 11 element, and one of the noble metals. It is one of the least reactive chemical elements, being the second-lowest in the reactivity series. It is solid under standard conditions. (Full article...)
-
Location of the Mariana Trench
The Mariana Trench is an oceanic trench located in the western Pacific Ocean, about 200 kilometres (124 mi) east of the Mariana Islands; it is the deepest oceanic trench on Earth. It is crescent-shaped and measures about 2,550 km (1,580 mi) in length and 69 km (43 mi) in width. The maximum known depth is 10,984 ± 25 metres (36,037 ± 82 ft; 6,006 ± 14 fathoms; 6.825 ± 0.016 mi) at the southern end of a small slot-shaped valley in its floor known as the Challenger Deep. The deepest point of the trench is more than 2 km (1.2 mi) farther from sea level than the peak of Mount Everest. (Full article...) -
Asbestos (/æsˈbɛstəs, æz-, -tɒs/ ass-BES-təs, az-, -toss) is a naturally occurring, carcinogenic, fibrous silicate mineral. There are six types, all of which are composed of long and thin fibrous crystals, each fibre (particulate with length substantially greater than width) being composed of many microscopic "fibrils" that can be released into the atmosphere by abrasion and other processes. Inhalation of asbestos fibres can lead to various dangerous lung conditions, including mesothelioma, asbestosis, and lung cancer. As a result of these health effects, asbestos is considered a serious health and safety hazard. (Full article...) -
The 2004 Indian Ocean tsunami at Ao Nang, Krabi Province, Thailand
A tsunami (/(t)suːˈnɑːmi, (t)sʊˈ-/ (t)soo-NAH-mee, (t)suu-; from Japanese: 津波, lit. 'harbour wave', pronounced [tsɯnami]) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and underwater explosions (including detonations, landslides, glacier calvings, meteorite impacts and other disturbances) above or below water all have the potential to generate a tsunami. Unlike normal ocean waves, which are generated by wind, or tides, which are in turn generated by the gravitational pull of the Moon and the Sun, a tsunami is generated by the displacement of water from a large event. (Full article...)
Featured pictures
Click to enlarge and view description.
Main articles
| Overviews |  | |
|---|---|---|
| History of geology | ||
| Composition and structure | ||
| Historical geology | ||
| Dynamic Earth | ||
| Water | ||
| Geodesy | ||
| Geophysics | ||
| Applications | ||
| Occupations | ||
Categories
Select [►] to view subcategories.
Selected pictures
-
Curiosity is a car-sized rover designed to explore the crater Gale on Mars as part of NASA's Mars Science Laboratory mission. It was launched from Cape Canaveral in November 2011 and landed on Aeolis Palus inside Gale on August 6, 2012, at 05:17 UTC. Curiosity's landing site, nicknamed Bradbury Landing, was less than 2.4 km (1.5 mi) from the center of the rover's touchdown target after a 560-million km (350-million mi) journey. The rover's goals include an investigation of the Martian climate and geology; assessment of whether the selected field site inside Gale has ever offered environmental conditions favorable for microbial life, including investigation of the role of water; as well as planetary habitability studies in preparation for human exploration.
This picture is a self-portrait of Curiosity on Mars at the "Big Sky" drilling site, where it collected a rock sample at the foothills of Aeolis Mons (Mount Sharp) in October 2015. The photograph combines dozens of images taken by the Mars Hand Lens Imager (MAHLI) camera at the end of the rover's robotic arm; the arm itself is not included, although its shadow is visible on the ground. Wrist motions and turret rotations on the arm allowed MAHLI to acquire the mosaic's component images. -
Map: Grandiose, based on a map by the United States Geological SurveyA geological map of Yosemite National Park (full size), showing the Cathedral Peak Granodiorite, the largest unit in the Tuolumne Intrusive Suite, which in turn is the largest granitic suite in the park.
Cathedral Peak Granodiorite
Rest of the Tuolumne Intrusive Suite -
Map: Strebe, using GeocartThe Lambert azimuthal equal-area projection is a projection used for mapping a sphere to a disk. It accurately represents area in all regions of the sphere, but it does not accurately represent angles. It is used in scientific disciplines such as geology for plotting the orientations of lines in three-dimensional space, and by the National Atlas of the US in its online map-making application. -
Cartographic relief depiction showing the varying age of bedrock underlying North America. This image combines a geologic map and a shaded relief image. This combination reveals the geologic history of North America through the interrelation of rock type, topography and time. Regional surface processes as well as continent-scale tectonic events are exposed in the three dimensions of space and the fourth dimension, geologic time. From most recent to oldest, age is indicated by color: yellow, green, blue, red. -
Image credit: Galileo spacecraftThis false-color mosaic showing compositional variations in the geology of the Moon was constructed from a series of 53 images taken through three spectral filters by the imaging system of the Galileo spacecraft. Bright pinkish areas are highlands materials, such as those surrounding the oval lava-filled Mare Crisium impact basin toward the bottom. Blue to orange shades indicate volcanic lava flows. To the left of Crisium, the dark blue Mare Tranquillitatis is richer in titanium than the green and orange maria above it. Thin mineral-rich soils associated with relatively recent impacts are represented by light blue colors. The monochrome band on the right edge shows the unretouched surface of the moon.
Associated Wikimedia
The following Wikimedia Foundation sister projects provide more on this subject:
-
Commons
Free media repository -
Wikibooks
Free textbooks and manuals -
Wikidata
Free knowledge base -
Wikinews
Free-content news -
Wikiquote
Collection of quotations -
Wikisource
Free-content library -
Wikiversity
Free learning tools -
Wikivoyage
Free travel guide -
Wiktionary
Dictionary and thesaurus
Discover Wikipedia using portals
