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.
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A map of Resolution Guyot's bathymetric relief Resolution Guyot (formerly known as Huevo) is a guyot(tablemount) in the underwater Mid-Pacific Mountains in the Pacific Ocean. It is a circular flat mountain, rising 500 metres (1,600ft) above the seafloor to a depth of about 1,320 metres (4,330ft), with a 35-kilometre-wide (22-mile) summit platform. The Mid-Pacific Mountains lie west of Hawaii and northeast of the Marshall Islands, but at the time of its formation, the guyot was located in the Southern Hemisphere.
An earthquake occurred on 22 June 2002 with the epicenter near the city of Bou'in-Zahra in Iran's Qazvin province. The region is crossed by several major faults and known for destructive earthquakes. The shock measured 6.5 on the Mwc scale, had a maximum Mercalli intensity of VIII (Severe), and was followed by more than 20 aftershocks. At least 261 people were killed and 1,500 more were injured.
According to the International Institute of Earthquake Engineering and Seismology (IIEES), the earthquake was felt as far away as the capital city of Tehran, approximately 290 kilometres (180mi) east of the epicenter, although no damage was reported there. Most houses in the region were single-story masonry buildings, and virtually all of these collapsed. Public anger arose due to the slow official response to victims who needed supplies. Residents of the town of Avaj resorted to throwing stones at the car of a government minister. (Full article...)
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The Cretaceous–Paleogene (K–Pg) extinction event, formerly known as the Cretaceous–Tertiary (K–T) extinction event, was a major mass extinction of three-quarters (75%) of the plant and animal species on Earth which occurred around 66million years ago. The event caused the extinction of all the non-avian dinosaurs and most other tetrapods weighing more than 25kg (55lb), excepting some ectothermic species such as sea turtles and crocodilians. It marked the ends of both the Cretaceous period and the Mesozoic era, and logged the beginning of the current geological era, the Cenozoic era.
A magnitude 6.4 Msearthquake struck Ecuador's Tungurahua Province southeast of its capital Ambato and killed 5,050people on August 5, 1949. The nearby villages of Guano, Patate, Pelileo, and Pillaro were destroyed, and the city of Ambato suffered heavy damage. The earthquake flattened buildings and subsequent landslides caused damage throughout the Tungurahua, Chimborazo, and Cotopaxi Provinces. It disrupted water mains and communication lines and opened a fissure into which the small town of Libertad sank. Moderate shaking from the event extended as far away as Quito and Guayaquil.
Earthquakes in Ecuador stem from two major interrelated tectonic areas: the subduction of the Nazca plate under the South American plate and the Andean Volcanic Belt. The 1949 Ambato earthquake initially followed an intersection of several northwest–southeast-trending faults in the Inter-Andean Valley which were created by the subduction of the Carnegie Ridge. Strata of rock cracked as the earthquake ruptured the faults, sending out powerful shock waves. Today threats exist throughout the country from both interplate and intraplate seismicity. (Full article...)
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Kolob Canyons from the end of Kolob Canyons Road. Stream erosion has incised the Kolob Plateau to form canyons that expose the red-orange colored Navajo Sandstone and other formations.
The geology of the Zion and Kolob canyons area includes nine known exposed formations, all visible in Zion National Park in the U.S. state of Utah. Together, these formations represent about 150 million years of mostly Mesozoic-aged sedimentation in that part of North America. Part of a super-sequence of rock units called the Grand Staircase, the formations exposed in the Zion and Kolob area were deposited in several different environments that range from the warm shallow seas of the Kaibab and Moenkopi formations, streams and lakes of the Chinle, Moenave, and Kayenta formations to the large deserts of the Navajo and Temple Cap formations and dry near shore environments of the Carmel Formation.
Subsequent uplift of the Colorado Plateau slowly raised these formations much higher than where they were deposited. This steepened the stream gradient of the ancestral rivers and other streams on the plateau. The faster-moving streams took advantage of uplift-created joints in the rocks to remove all Cenozoic-aged formations and cut gorges into the plateaus. Zion Canyon was cut by the North Fork of the Virgin River in this way. Lava flows and cinder cones covered parts of the area during the later part of this process. (Full article...)
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An 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 (170mi) 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 50,000homeless and damaged or destroyed over 15,000homes—was described as the deadliest of 1997 by the United States Geological Survey. Some 155aftershocks 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 $100million, 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...)
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Io, with two plumes erupting from its surface, Galileo image, June 1997 Io, a moon of Jupiter, has a substantial presence of volcanoes, volcanic pits and lava flows on its surface. Volcanic activity on the moon was first 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 five known currently volcanically or cryovolcanically active worlds in the Solar System (the others being Earth, Venus, 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...)
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Isoseismal map for the event (I–III are Not felt to Weak, IV is Light, V is Moderate, VI is Strong, VII is Very strong)
The U.S. Midwestern state of Illinois was struck by its largest recorded earthquake (a New Madrid event) in 1968. Striking at 11:02a.m. on November9, it measured 5.3 on the Richter scale. Although no fatalities occurred, the event caused considerable structural damage to buildings, including the toppling of chimneys and shaking in Chicago, the region's largest city. The earthquake was one of the most widely felt in U.S. history, largely affecting 23states over an area of 580,000sqmi (1,500,000km2). In studying its cause, scientists discovered the Cottage Grove Fault in the Southern Illinois Basin.
Within the region, millions felt the rupture. Reactions to the earthquake varied; some people near the epicenter did not react to the shaking, while others panicked. A future earthquake in the region is extremely likely; in 2005, seismologists and geologists estimated a 90% chance of a magnitude 6–7 tremor before 2055, likely originating in the Wabash Valley seismic zone on the Illinois–Indiana border or the New Madrid fault zone. (Full 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 200million to nearly 2billion 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 lithifiedsand 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 75million 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 (3.2km). The adjacent Basin and Range Province to the west started to form about 18million 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...)
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Anning with her dog, Tray, painted before 1842; the hill Golden Cap can be seen in the background.
Anning searched for fossils in the area's Blue Lias and Charmouth Mudstone cliffs, particularly during the winter months when landslides exposed new fossils that had to be collected quickly before they were lost to the sea. Her discoveries included the first correctly identified ichthyosaur skeleton when she was twelve years old; the first two nearly complete plesiosaur skeletons; the first pterosaur skeleton located outside Germany; and fish fossils. Her observations played a key role in the discovery that coprolites, known as bezoar stones at the time, were fossilised faeces, and she also discovered that belemnite fossils contained fossilised ink sacs like those of modern cephalopods. (Full article...)
El Tatio is a geothermal field with many geysers located in the Andes Mountains of northern Chile at 4,320 metres (14,170ft) above mean sea level. It is the third-largest geyser field in the world and the largest in the Southern Hemisphere. Various meanings have been proposed for the name "El Tatio", including "oven" or "grandfather". The geothermal field has many geysers, hot springs, and associated sinter deposits. The water from these hot springs eventually forms the Rio Salado, a major tributary of the Rio Loa, significantly increasing the amount of arsenic in the river. The geothermal vents are sites of populations of extremophile microorganisms such as hyperthermophiles, and El Tatio has been studied as an analogue for the early Earth and possible past life on Mars. (Full article...)
Alfred Georg Hubertus Fischer (December 12, 1920 – July 2, 2017) was a German-Americangeologist. Among his influential work was the examination of the climate record over geological time scales and latitudinal gradients in species diversity and numbers across geological time. (Full article...)
... 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 WarI?
On 24 June 2026, doublet large strike-slip earthquakes affected northwestern and central Venezuela. The epicenter of the first earthquake was in Veroes Municipality, west of San Felipe, the capital city of Yaracuy. This earthquake, which measured Mw7.2, occurred at 18:04 VET and was classified as a foreshock. It was followed by a Mw7.5 mainshock 30 seconds later centered off the coast of La Guaira, west of Catia La Mar. The two earthquakes caused widespread damage across the country, particularly in the capital Caracas and especially the state of La Guaira, where 80% of buildings collapsed. As of August 2026, at least 6,500 fatalities were officially confirmed, about 226,700 were injured or hospitalized, and tens of thousands still remain missing. (Full article...)
Mount Everest (known in Nepali as Sagarmāthā, in Sherpa as Chamolangma, and in Tibetan as Jomolangma/Čhomolangma is the highest mountain on Earth above sea level. It lies in the Mahalangur Himal sub-range of the Himalayas and marks part of the China–Nepal border at its summit. Its height was most recently measured in 2020 through a joint survey by Nepalese and Chinese authorities as 8,848.86m (29,031ft 8+1⁄2in). (Full article...)
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Animated, colour-coded map showing four to seven continents – depending on the convention and model, some continents may be consolidated or subdivided.
A continent is any of several large terrestrial geographical regions. Continents are generally identified by convention rather than any strict criteria. A continent could be a single large landmass, a landmass and nearby islands either on or beyond its continental shelf, or a part of a larger landmass, as in the case of Asia and Europe within Eurasia. Due to these varying definitions, the number of continents varies, up to seven or as few as four. Most English-speaking countries recognize seven continents. In order from largest to smallest in area, these seven are Asia, Africa, North America, South America, Antarctica, Europe, and Australia (or Oceania or Australasia). Different variations with fewer continents merge some of these regions; examples of this are merging Asia and Europe into Eurasia, North America and South America into the Americas (or simply America), and Africa, Asia, and Europe into Afro-Eurasia. (Full article...)
Earthquakes (6.0+ Mw) between 1900 and 2017 Earthquakes are caused by movements within the Earth's crust and uppermost mantle. They range from weak events detectable only by seismometers, to sudden and violent events lasting many minutes which have caused some of the biggest disasters in human history. Below, there are earthquakes listed by period, region or country, year, magnitude, cost, fatalities, and number of scientific studies. (Full article...)
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Imaging from NASA's Shuttle Radar Topography Mission STS-99 reveals part of the diameter ring of the crater in the form of a shallow circular trough. Numerous cenotes (sinkholes) cluster around the trough marking the inner crater rim.
The Pacific Ring of Fire, with trenches marked with blue lines The Ring of Fire (also known as the Pacific Ring of Fire, the Rim of Fire, the Girdle of Fire or the Circum-Pacific belt) is a tectonic belt of earthquakes and volcanoes. (Full article...)
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Location of the Mariana Trench
The Mariana Trench is the deepest oceanic trench on Earth, located in the western Pacific Ocean, about 200 kilometers (124mi) east of the Mariana Islands. It is crescent-shaped and measures about 2,550km (1,580mi) in length and 69km (43mi) in width. The maximum known depth is 10,935±6 meters (35,876±20ft; 5,979.3±3.3 fathoms; 6.7947±0.0037mi) at the southern end of a small slot-shaped valley in its floor known as the Challenger Deep. This makes the deepest point of the trench more than 2km (1.2mi) farther from sea level than the peak of Mount Everest. (Full article...)
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 November2011 and landed on Aeolis Palus inside Gale on August6, 2012, at 05:17UTC. Curiosity's landing site, nicknamed Bradbury Landing, was less than 2.4km (1.5mi) from the center of the rover's touchdown target after a 560-millionkm (350-millionmi) 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 October2015. 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.
The 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.
A 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
This 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 Crisiumimpact 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.
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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.
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.
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.
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.
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