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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Bryce Canyon National Park (/braɪs/) is a national park of the United States located in southwestern Utah. The major feature of the park is Bryce Canyon, which, despite its name, is not a canyon but a collection of giant natural amphitheaters along the eastern side of the Paunsaugunt Plateau. Bryce is distinctive due to geological structures called hoodoos, formed by frost weathering and stream erosion of the river and lake bed sedimentary rock. The red, orange, and white colors of the rocks provide distinctive views for park visitors. Bryce Canyon National Park is much smaller and sits at a much higher elevation than nearby Zion National Park. The rim at Bryce varies from 8,000 to 9,000 feet (2,400 to 2,700 m).
The area is in portions of Garfield County and Kane County. It was settled by Mormon pioneers in the 1850s and was named after Ebenezer Bryce, who homesteaded in the area in 1874. The area was originally designated as a national monument by President Warren G. Harding in 1923 and was redesignated as a national park by Congress in 1928. The park covers 35,835 acres (55.992 sq mi; 14,502 ha; 145.02 km2) and receives substantially fewer visitors than Zion National Park (nearly 4.3 million in 2016) or Grand Canyon National Park (almost 6 million in 2016), largely due to Bryce's more remote location. In 2024, Bryce Canyon received almost 2.5million visitors. (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 Chicxulub crater is an impact crater buried underneath the Yucatán Peninsula in Mexico. The crater is named after the onshore inland community of Chicxulub Pueblo. 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 two hundred kilometers (120 mi) in diameter and is buried to a depth of about one kilometer (0.6 mi) beneath younger sedimentary rocks. It is one of the largest impact structures on Earth, alongside the much older Sudbury and Vredefort impact structures, and the only one whose peak ring is intact and directly accessible for scientific research.
The crater was discovered by Antonio Camargo and Glen Penfield, geophysicists who had been looking for petroleum in the Yucatán Peninsula during the late 1970s. Penfield was initially unable to obtain evidence that the geological feature was a crater and gave up his search. Later, through contact with Alan R. Hildebrand in 1990, Penfield obtained samples that suggested it was an impact feature. Evidence for the crater's impact origin includes shocked quartz, a gravity anomaly, and tektites in surrounding areas. (Full article...)
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Artist's concept of the Earth 5–7.5 billion years from now, when the Sun has become a red giant
While the future cannot be predicted with certainty, present understanding in various scientific fields allows for the prediction of some far-future events, if only in the broadest outline. These fields include astrophysics, which studies how planets and stars form, interact and die; particle physics, which has revealed how matter behaves at the smallest scales; evolutionary biology, which studies how life evolves over time; plate tectonics, which shows how continents shift over millennia; and sociology, which examines how human societies and cultures evolve.
These timelines begin at the start of the 4th millennium in 3001 CE, and continue until the furthest and most remote reaches of future time. They include alternative future events that address unresolved scientific questions, such as whether humans will become extinct, whether the Earth survives when the Sun expands to become a red giant and whether proton decay will be the eventual end of all matter in the universe. (Full article...)
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Tourists in a sea cave in the Galápagos Islands The following outline provides an overview of and topical guide to natural caves. The word cave is loosely defined, but most commonly refers to a natural opening large enough to be entered by a human. These landforms are common around the world, and have even been detected on the Moon and Mars. This outline's scope is limited to these natural formations, specifically excluding the rock-cut features which are often referred to as caves in Eastern Asia. (Full article...)
The first magmatic cycle took place between 7.5 and 6 million years ago and is represented by the Raspberry, Little Iskut and Armadillo formations, each of which is the product of a different eruptive period. Three distinct periods of eruptive activity also characterized the second magmatic cycle between 6 and 1 million years ago; they are represented by the Nido, Spectrum and Pyramid geological formations. The third magmatic cycle about 1 million years ago is represented by the Ice Peak, Pillow Ridge and Edziza geological formations, each of which is also the product of a distinct eruptive period. Three distinct periods of eruptive activity also characterized the fourth magmatic cycle between 0.8 and 0.2 million years ago which are represented by the Arctic Lake, Klastline and Kakiddi geological formations. The fifth magmatic cycle began at least 20,000 years ago and may be ongoing; the single distinct eruptive period of this magmatic cycle is represented by the Big Raven Formation. (Full article...)
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A magnitude 6.4 Msearthquake struck Ecuador's Tungurahua Province southeast of its capital Ambato and killed 5,050 people 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...)
The last picture taken of Johnston on May 17, 1980, 13 hours before his death at the eruption site
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. 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 is one of two American volcanologists known to have died in a volcanic eruption; the other is his student Harry Glicken. (Full article...)
The eruption was preceded by a series of earthquakes and steam-venting episodes caused by an injection of magma at shallow depth below the volcano that created a large bulge and a fracture system on the mountain's north slope. An earthquake at 8:32:11am PDT (UTC−7) on May 18, 1980, caused the entire weakened north face to slide away, a sector collapse which was the largest subaerial landslide in recorded history. This allowed the partly molten rock, rich in high-pressure gas and steam, to suddenly explode northward toward Spirit Lake in a hot mix of lava and pulverized rock, overtaking the landslide. An eruption column rose 80,000 feet (24 km; 15 mi) into the atmosphere and deposited ash in 11 U.S. states and various Canadian provinces. At the same time, snow, ice, and several entire glaciers on the volcano melted, forming a series of large lahars (volcanic mudslides) that reached as far as the Columbia River, nearly 50 miles (80 km; 260,000 ft) to the southwest. Less severe outbursts continued into the next day, only to be followed by other large, but not as destructive, eruptions later that year. The thermal energy released during the eruption was equal to 26 megatons of TNT. (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 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 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 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...)
A mudpot, or mud pool, is a type of acidic hot spring, or fumarole, with limited water. It usually takes the form of a pool of bubbling mud, as a result of the acid and microorganisms decomposing surrounding rock into clay and mud. (Full article...)
Hans Wilhelm Stille (8 October 1876 – 26 December 1966) was an influential Germangeologist working primarily on tectonics and the collation of tectonic events during the Phanerozoic. Stille adhered to the contracting Earthhypothesis and together with Leopold Kober he worked on the geosyncline theory to explain orogeny. Stille's ideas emerged in the aftermath of Eduard Suess' book Das Antlitz der Erde (1883–1909). Stille's and Kober's school of thought was one of two that emerged in the post-Suess era (the other being headed by Alfred Wegener and Émile Argand.) Their competing view rejected Earth contraction and argued for continental drift. As Stille opposed continental drift he came to be labelled a "fixist".
... that geologist E. Dale Jackson conducted experiments with Jello to test theories on the formation of the Hawaiian islands?
... 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?
On 24 June 2026, two 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 Mw 7.2, occurred at 18:04 VET and was classified as a foreshock. It was followed by a Mw 7.5 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 July 2026, it has been confirmed that more than 5,500 people were killed, 16,700 were injured, and tens of thousands still remain missing. (Full article...)
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 sometimes 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 kilometres (124 mi) east of the Mariana Islands. 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 10,935 ± 6 metres (35,876 ± 20 ft; 5,979.3 ± 3.3 fathoms; 6.7947 ± 0.0037 mi) 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 2 km (1.2 mi) 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 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.
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.
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
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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.
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.
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: 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.
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.
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