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The Earth Sciences Portal

Earth seen from Moon

Earth science orgeoscience includes all fields ofnatural science related to the planetEarth. This is a branch of science dealing with the physical, chemical, and biological complex constitutions and synergistic linkages of Earth's four spheres: thebiosphere,hydrosphere/cryosphere,atmosphere, andgeosphere (orlithosphere). Earth science can be considered to be a branch ofplanetary science but with a much older history. (Full article...)

Selected articles

Image 1

Grand Canyon of the Yellowstone

Yellowstone National Park is anational park of the United States located in the northwest corner ofWyoming and extending intoMontana andIdaho. It was established by the42nd U.S. Congress through theYellowstone National Park Protection Act and signed into law byPresident Ulysses S. Grant on March 1, 1872. Yellowstone was the first national park in the U.S. and is also widely held to be the first national park in the world. The park is known forits wildlife andits many geothermal features, especially theOld Faithful geyser, one of its most popular. While it represents many types ofbiomes, thesubalpine forest is the most abundant. It is part of theSouth Central Rockies forests ecoregion.

While Native Americans have lived in the Yellowstone region for at least 11,000 years, aside from visits bymountain men during the early-to-mid-19th century, organized exploration did not begin until the late 1860s. Management and control of the park originally fell under the jurisdiction of theU.S. Department of the Interior, the firstsecretary of the interior to supervise the park beingColumbus Delano. However, the U.S. Army was eventually commissioned to oversee the management of Yellowstone for 30 years between 1886 and 1916. In 1917, the administration of the park was transferred to theNational Park Service, which had been created the previous year. Hundreds of structures have been built and are protected for their architectural andhistorical significance, and researchers have examined more than a thousand indigenousarchaeological sites. (Full article...)
Image 2
Changes insurface air temperature over the past 50 years. TheArctic has warmed the most, and temperatures on land have generally increased more thansea surface temperatures.

Present-dayclimate change includes bothglobal warming—the ongoing increase inglobal average temperature—and its wider effects on Earth’sclimate system.Climate change in a broader sense also includes previous long-term changes to Earth'sclimate. The current rise in global temperatures isdriven by human activities, especiallyfossil fuel burning since theIndustrial Revolution. Fossil fuel use,deforestation, and someagricultural andindustrial practices releasegreenhouse gases. These gasesabsorb some of the heat that the Earthradiates after it warms fromsunlight, warming the lower atmosphere.Carbon dioxide, the primary gas driving global warming,has increased in concentration by about 50% since the pre-industrial era to levels not seen for millions of years.

Climate change has an increasingly largeimpact on the environment.Deserts are expanding, whileheat waves andwildfires are becoming more common.Amplified warming in the Arctic has contributed to thawingpermafrost,retreat of glaciers andsea ice decline. Higher temperatures are also causingmore intense storms, droughts, and otherweather extremes. Rapid environmental change inmountains,coral reefs, andthe Arctic is forcing many species to relocate orbecome extinct. Even if efforts to minimize future warming are successful, some effects will continue for centuries. These includeocean heating,ocean acidification andsea level rise. (Full article...)
Image 3

The BerlinArchaeopteryx specimen (A. siemensii)

Archaeopteryx (/ˌɑːrkiːˈɒptərɪks/;lit. 'old-wing'), sometimes referred to by its German name, "Urvogel" (lit.Primeval Bird) is a genus ofbird-likedinosaurs. The name derives from theancient Greekἀρχαῖος (archaîos), meaning "ancient", andπτέρυξ (ptéryx), meaning "feather" or "wing". Between the late 19th century and the early 21st century,Archaeopteryx was generally accepted bypalaeontologists and popular reference books as the oldest known bird (member of the groupAvialae). Older potentialavialans have since been identified, includingAnchiornis,Xiaotingia,Aurornis, andBaminornis.

Archaeopteryx lived in theLate Jurassic around 150 million years ago, in what is now southern Germany, during a time when Europe was anarchipelago of islands in a shallow warm tropical sea, much closer to theequator than it is now. Similar in size to aEurasian magpie, with the largest individuals possibly attaining the size of araven, the largest species ofArchaeopteryx could grow to about 0.5 m (1 ft 8 in) in length. Despite their small size, broad wings, and inferred ability to fly or glide,Archaeopteryx had more in common with other smallMesozoic dinosaurs than with modern birds. In particular, they shared the following features with thedromaeosaurids andtroodontids: jaws with sharpteeth, three fingers withclaws, a long bony tail, hyperextensible second toes ("killing claw"), feathers (which also suggestwarm-bloodedness), and various features of theskeleton. (Full article...)
Image 4

The Blue Marble,Apollo 17, December 1972

Earth is the thirdplanet from theSun and the onlyastronomical object known toharbor life. This is enabled by Earth being anocean world, the only one in theSolar System sustaining liquidsurface water. Almost all of Earth's water is contained in its global ocean, covering70.8% ofEarth's crust. The remaining 29.2% of Earth's crust is land, most of which is located in the form ofcontinental landmasses within Earth'sland hemisphere. Most of Earth's land is at least somewhathumid and covered by vegetation, while largesheets of ice atEarth's polar deserts retain more water than Earth'sgroundwater, lakes, rivers, andatmospheric water combined. Earth's crust consists of slowly movingtectonic plates, which interact to produce mountain ranges,volcanoes, and earthquakes.Earth has a liquid outer core that generates amagnetosphere capable of deflecting most of the destructivesolar winds andcosmic radiation.

Earth hasa dynamic atmosphere, which sustains Earth's surface conditions and protects it from mostmeteoroids andUV-light at entry. It has a composition of primarilynitrogen andoxygen.Water vapor is widely present in the atmosphere,forming clouds that cover most of the planet. The water vapor acts as agreenhouse gas and, together with other greenhouse gases in the atmosphere, particularlycarbon dioxide (CO₂), creates the conditions for both liquid surface water and water vapor to persist via the capturing ofenergy from the Sun's light. This process maintains the current average surface temperature of 14.76 °C (58.57 °F), at which water is liquid under normal atmospheric pressure. Differences in the amount of captured energy between geographic regions (as with theequatorial region receiving more sunlight than the polar regions) driveatmospheric andocean currents, producing a globalclimate system with differentclimate regions, and a range of weather phenomena such asprecipitation, allowing components such asnitrogen tocycle. (Full article...)
Image 5
Old Faithful erupting atYellowstone National Park

Ageyser (/ˈɡaɪzər/,UK:/ˈɡiːzər/) is aspring with an intermittent water discharge ejected turbulently and accompanied by steam. The formation of geysers is fairly rare and is caused by particularhydrogeological conditions that exist only in a few places on Earth.

Generally, geyser field sites are located near activevolcanic areas, and the geyser effect is due to the proximity ofmagma. Surface water works its way down to an average depth of around 2,000 metres (6,600 ft) where it contacts hot rocks. The pressurized water boils, and this causes the geyser effect of hot water and steam spraying out of the geyser's surface vent. (Full article...)
Image 6
Thetornado outbreak of April 6–8, 2006, was a majortornado outbreak in thecentral and parts of the southern United States that began on April 6, 2006, in theGreat Plains and continued until April 8 inSouth Carolina, with most of the activity on April 7. The hardest-hit region wasMiddle Tennessee, where several strong tornadoes devastated entire neighborhoods and left ten people dead. Some of the worst damage took place inGallatin, Tennessee, and other communities north ofNashville also sustained significant damage.

There were 73 tornadoes confirmed across 13 states, with the bulk of them coming on the afternoon and evening of April 7 across the South, particularly inTennessee. In total, 10 deaths were reported as a result of the tornadoes, and over $650 million in damage was reported, of which over $630 million was in Middle Tennessee. It was the third major outbreak of 2006, occurring just days afteranother major outbreak on April 2. It was also considered by some to be the worst disaster event in Middle Tennessee since the1998 tornado outbreak. (Full article...)
Image 7

The2002 Bou'in-Zahra earthquake (also known as the2002 Avaj earthquake or the2002 Changureh earthquake) occurred on 22 June 2002. Theepicenter was near the city ofBou'in-Zahra inQazvin province, a region of northwesternIran which is crossed by several majorfaults that is known for destructive earthquakes. The shock measured 6.5 on theM_wc scale, had a maximumMercalli intensity of VIII (Severe), and was followed by more than 20aftershocks. At least 230 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 ofTehran, approximately 290 kilometres (180 mi) east of the epicenter, although no damage was reported there. Most houses in the region were single-storymasonry buildings, and virtually all of these collapsed. The public became angry due to the slow official response to victims who needed supplies. Residents of the town ofAvaj resorted to throwing stones at the car of a government minister. (Full article...)
Image 8
Calabozos is aHolocene caldera in centralChile'sMaule Region (7th Region). Part of the ChileanAndes' volcanic segment, it is considered a member of theSouthern Volcanic Zone (SVZ), one of the three distinct volcanic belts of South America. This most active section of the Andes runs along central Chile's western edge, and includes more than 70 of Chile'sstratovolcanoes and volcanic fields. Calabozos lies in an extremely remote area of poorly glaciated mountains.

Calabozos and the majority of the Andean volcanoes formed from thesubduction of the oceanicNazca Plate under the continentalSouth American continental lithosphere. The caldera is in a transitional region between thick and thinlithosphere, and is probably supplied by a pool ofandesitic andrhyolitic magma. It sits on a historic bed of volcanic andplutonic sedimentary rock (rock formed within the Earth) that in turn sits on top of a layer of merged sedimentary andmetamorphic rock. (Full article...)
Image 9

View of Mount Samalas along with Mount Rinjani

In 1257, a catastrophic eruption occurred at Samalas, avolcano on the Indonesian island ofLombok. The event had a probableVolcanic Explosivity Index of 7, making it one of the largest volcanic eruptions during theHolocene epoch. It left behind a largecaldera that containsLake Segara Anak. Later volcanic activity created more volcanic centres in the caldera, including the Barujari cone, which remains active.

The event createderuption columns reaching tens of kilometres into the atmosphere andpyroclastic flows that buried much of Lombok and crossed the sea to reach the neighbouring island ofSumbawa. The flows destroyed human habitations, including the city ofPamatan, which was the capital of a kingdom on Lombok. Ash from the eruption fell as far as 340 kilometres (210 mi) away inJava; the volcano deposited more than 10 cubic kilometres (2.4 cu mi) of rocks and ash. (Full article...)
Image 10
Life in the Ediacaran Period as imagined by researchers in 1980.

TheEdiacaran (/ˌiːdiˈækərən/; formerlyVendian)biota is ataxonomic period classification that consists of all life forms that were present on Earth during theEdiacaran Period (c. 635–538.8 Mya). These were enigmatic tubular and frond-shaped, mostlysessile, organisms.Trace fossils of these organisms have been found worldwide, and represent the earliest known complexmulticellular organisms. The term "Ediacara biota" has received criticism from some scientists due to its alleged inconsistency, arbitrary exclusion of certain fossils, and inability to be precisely defined.

The Ediacaran biota may have undergoneevolutionary radiation in a proposed event called theAvalon explosion,575 million years ago. This was after the Earth had thawed from theCryogenian period'sextensive glaciation. This biota largely disappeared with the rapid increase inbiodiversity known as theCambrian explosion. Most of the currently existingbody plans ofanimals first appeared in thefossil record of theCambrian rather than the Ediacaran. For macroorganisms, the Cambrian biota appears to have almost completely replaced the organisms that dominated the Ediacaran fossil record, although relationships are still a matter of debate. (Full article...)
Image 11

Turquoise is anopaque,blue-to-green mineral that is ahydrous phosphate ofcopper andaluminium, with thechemical formulaCu Al₆(PO₄)₄(OH)₈·4H₂O. It is rare and valuable in finer grades and has been prized as agemstone for millennia due to its hue.

Like most other opaque gems, turquoise has been devalued by the introduction of treatments, imitations, and synthetics into the market. Therobin egg blue orsky blue color of thePersian turquoise mined near the modern city ofNishapur,Iran, has been used as a guiding reference for evaluating turquoise quality. (Full article...)
Image 12

Lili near peak intensity in theGulf of Mexico on October 2

Hurricane Lili was the second costliest, deadliest, and most intensehurricane of the2002 Atlantic hurricane season, only surpassed byHurricane Isidore, which affected the same areas around a week before Lili. Lili was the twelfth named storm, fourth hurricane, and second major hurricane of the 2002 Atlantic hurricane season. The storm developed from a tropical disturbance in the open Atlantic on September 21. It continued westward, affecting theLesser Antilles as a tropical storm, then entered the Caribbean. As it moved west, the storm dissipated while being affected bywind shear south ofCuba, and regenerated when the vertical wind shear weakened. It turned to the northwest and strengthened up tocategory 2 strength on October 1. Lili made twolandfalls in western Cuba later that day, and then entered theGulf of Mexico. The hurricane rapidly strengthened on October 2, reaching Category 4 strength that afternoon. It weakened rapidly thereafter, and hitLouisiana as a Category 1 hurricane on October 3. It moved inland and dissipated on October 6.

Lili caused extensive damage through the Caribbean, particularly to crops and poorly built homes. Mudslides were common on the more mountainous islands, particularly Haiti and Jamaica. In the United States, the storm cut off the production of oil within the Gulf of Mexico, and caused severe damage in parts of Louisiana. Lili was also responsible for severe damage to the barrier islands and marshes in the southern portion of the state. Total damage amounted to $925 million (2002 USD), and the storm killed 15 people during its existence. (Full article...)
$Image 13 Map of Earth's 16 principal tectonic plates Divergent:   Extension zone Convergent:   Collision zone Transform:   Sinistral transform Plate tectonics (from Latin tectonicus, from Ancient Greek τεκτονικός (tektonikós) 'pertaining to building') is the scientific theory that the Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of continental drift, an idea developed during the first decades of the 20th century. Plate tectonics came to be accepted by geoscientists after seafloor spreading was validated in the mid-to-late 1960s. The processes that result in plates and shape Earth's crust are called tectonics. Tectonic plates also occur in other planets and moons. Earth's lithosphere, the rigid outer shell of the planet including the crust and upper mantle, is fractured into seven or eight major plates (depending on how they are defined) and many minor plates or "platelets". Where the plates meet, their relative motion determines the type of plate boundary (or fault): convergent, divergent, or transform. The relative movement of the plates typically ranges from zero to 10 cm annually. Faults tend to be geologically active, experiencing earthquakes, volcanic activity, mountain-building, and oceanic trench formation. (Full article...)$
Image 13
Map of Earth's 16 principal tectonic plates

Divergent:
  Extension zone
Convergent:
  Collision zone
Transform:
  Sinistral transform

Plate tectonics (from Latin tectonicus, from Ancient Greek τεκτονικός (tektonikós) 'pertaining to building') is thescientific theory that theEarth'slithosphere comprises a number of largetectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept ofcontinental drift, an idea developed during the first decades of the 20th century. Plate tectonics came to be accepted bygeoscientists afterseafloor spreading was validated in the mid-to-late 1960s. The processes that result in plates and shapeEarth's crust are calledtectonics.
Tectonic plates also occur in other planets and moons.

Earth's lithosphere, the rigid outer shell of the planet including thecrust andupper mantle, is fractured into seven or eight major plates (depending on how they are defined) and many minor plates or "platelets". Where the plates meet, their relative motion determines the type ofplate boundary (orfault):convergent,divergent, ortransform. The relative movement of the plates typically ranges from zero to 10 cm annually. Faults tend to be geologically active, experiencingearthquakes,volcanic activity,mountain-building, andoceanic trench formation. (Full article...)
$Image 14 The ACFEL ice auger showing an ice core pushed up into the core remover barrel. Ice drilling allows scientists studying glaciers and ice sheets to gain access to what is beneath the ice, to take measurements along the interior of the ice, and to retrieve samples. Instruments can be placed in the drilled holes to record temperature, pressure, speed, direction of movement, and for other scientific research, such as neutrino detection. Many different methods have been used since 1840, when the first scientific ice drilling expedition attempted to drill through the Unteraargletscher in the Alps. Two early methods were percussion, in which the ice is fractured and pulverized, and rotary drilling, a method often used in mineral exploration for rock drilling. In the 1940s, thermal drills began to be used; these drills melt the ice by heating the drill. Drills that use jets of hot water or steam to bore through ice soon followed. A growing interest in ice cores, used for palaeoclimatological research, led to ice coring drills being developed in the 1950s and 1960s, and there are now many different coring drills in use. For obtaining ice cores from deep holes, most investigators use cable-suspended electromechanical drills, which use an armoured cable to carry electrical power to a mechanical drill at the bottom of the borehole. (Full article...)$
Image 14
The ACFEL ice auger showing an ice core pushed up into the core remover barrel.

Ice drilling allows scientists studyingglaciers andice 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 asneutrino detection.

Many different methods have been used since 1840, when the first scientific ice drilling expedition attempted to drill through theUnteraargletscher in theAlps. 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 inice cores, used forpalaeoclimatological 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...)
Image 15

Imaging fromNASA's Shuttle Radar Topography MissionSTS-99 reveals part of the diameter ring of the crater in the form of a shallow circular trough. Numerouscenotes (sinkholes) cluster around the trough marking the inner crater rim.

TheChicxulub crater (/tʃiːkʃuːˈluːb/cheek-shoo-LOOB;Spanish:[tʃikʃuˈlub]^ⓘ) is animpact crater buried underneath theYucatán Peninsula in Mexico. Its center is offshore, but the crater is named after the onshore community ofChicxulub Pueblo (not the larger coastal town ofChicxulub Puerto). It was formed slightly over 66million years ago when anasteroid, about ten kilometers (six miles) in diameter, struckEarth. The crater is estimated to be 200 kilometers (120 miles) in diameter and 1 kilometer (0.62 miles) in depth. It is believed to bethe second largest impact structure on Earth, and the only one whosepeak 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 withAlan R. Hildebrand in 1990, Penfield obtained samples that suggested it was an impact feature. Evidence for the crater's impact origin includesshocked quartz, agravity anomaly, andtektites in surrounding areas. (Full article...)
Image 16

Anning with her dog, Tray, painted before 1842; the hillGolden Cap can be seen in the background

Mary Anning (21 May 1799 – 9 March 1847) was an Englishfossil collector,dealer, andpalaeontologist. She became known internationally for her discoveries inJurassic marinefossil beds in the cliffs along theEnglish Channel atLyme Regis in the county ofDorset,Southwest England. Anning's findings contributed to changes in scientific thinking aboutprehistoric life and thehistory of the Earth.

Anning searched for fossils in the area'sBlue Lias andCharmouth 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 identifiedichthyosaur skeleton when she was twelve years old; the first two nearly completeplesiosaur skeletons; the firstpterosaur skeleton located outside Germany; and fish fossils. Her observations played a key role in the discovery thatcoprolites, known asbezoar stones at the time, were fossilisedfaeces, and she also discovered thatbelemnite fossils contained fossilisedink sacs like those of moderncephalopods. (Full article...)
Image 17

Gloria near peak intensity north ofHispaniola on September 24

Hurricane Gloria was a powerfultropical cyclone that caused significant damage along theEast Coast of the United States and inAtlantic Canada during the1985 Atlantic hurricane season. It was the first significant tropical cyclone to strike the northeastern United States sinceHurricane Agnes in1972 and the first major storm to affect New York City andLong Island directly sinceHurricane Donna in1960. Gloria was aCape Verde hurricane originating from atropical wave on September 16 in the eastern Atlantic Ocean. After remaining a weak tropical cyclone for several days, Gloria intensified into a hurricane on September 22 north of theLesser Antilles. During that time, the storm had moved generally westward, although it turned to the northwest due to a weakening of theridge. Gloria quickly intensified on September 24, and the next day reached peak winds of 145 mph (233 km/h). The hurricane weakened before striking theOuter Banks of North Carolina on September 27. Later that day, Gloria made two subsequent landfalls onLong Island and across the coastline of westernConnecticut, before becomingextratropical on September 28 over New England. The remnants moved through Atlantic Canada and went on to impact Western Europe, eventually dissipating on October 4.

Before Gloria made landfall, theNational Hurricane Center issuedhurricane warnings at some point for theEast Coast of the United States from South Carolina to Maine. Hundreds of thousands of people evacuated, and the hurricane was described as the "storm of the century." In general, Gloria's strongest winds remained east of the center, which largely spared locations from North Carolina to New Jersey, and the passage at low tide reducedstorm surge. Hurricane-force winds and gusts affected much of the path, which knocked down trees and power lines. This left over 4 million people without power, causing the worst power outage in Connecticut history related to a natural disaster. Fallen trees caused six of the storm's fourteen deaths. (Full article...)
Image 18

Yosemite Valley fromTunnel View

Yosemite National Park (/joʊˈsɛmɪti/yoh-SEM-ih-tee) is anational park of the United States inCalifornia. It is bordered on the southeast bySierra National Forest and on the northwest byStanislaus National Forest. The park is managed by theNational Park Service and covers 759,620 acres (1,187 sq mi; 3,074 km²) in fourcounties – centered inTuolumne andMariposa, extending north and east toMono and south toMadera. Designated aWorld Heritage Site in 1984, Yosemite is internationally recognized for its granite cliffs, waterfalls, clear streams, groves ofgiant sequoia, lakes, mountains, meadows, glaciers, andbiological diversity. Almost 95 percent of the park is designatedwilderness. Yosemite is one of the largest and least fragmented habitat blocks in theSierra Nevada.

Itsgeology is characterized bygranite and remnants of older rock. About 10 million years ago, the Sierra Nevada wasuplifted and tilted to form its unique slopes, which increased the steepness of stream and river beds, forming deep, narrow canyons. About one million years agoglaciers formed at higher elevations. They moved downslope, cutting and sculpting the U-shapedYosemite Valley. (Full article...)
Image 19
Alaska'sMcCarty Glacier retreated about 15 kilometres (9.3 mi) in less than a century, and dense, diverse vegetation has become established on the slopes.

Theretreat of glaciers since 1850 is a well-documentedeffect of climate change. The retreat ofmountain glaciers provide evidence for therise in global temperatures since the late 19th century. Examples include mountain glaciers in western North America, Asia,the Alps in central Europe, andtropical andsubtropical regions of South America and Africa. Since glacial mass is affected by long-term climatic changes, e.g.precipitation,mean temperature, andcloud cover, glacial mass changes are one of the most sensitive indicators ofclimate change. The retreat of glaciers is also a major reason forsea level rise. Excluding peripheral glaciers ofice sheets, the total cumulated global glacial losses over the 26 years from 1993 to 2018 were likely 5500 gigatons, or 210 gigatons per year.

On Earth, 99% of glacial ice is contained within vastice sheets (also known as "continental glaciers") in thepolar regions. Glaciers also exist inmountain ranges on every continent other than the Australian mainland, including Oceania's high-latitudeoceanic island countries such asNew Zealand. Glacial bodies larger than 50,000 km² (19,000 sq mi) are calledice sheets. They are several kilometers deep and obscure the underlying topography. (Full article...)
Image 20
Ice core sample taken from drill

Anice core is acore sample that is typically removed from anice sheet or a high mountainglacier. Since the ice forms from the incremental buildup of annual layers of snow, lower layers are older than upper ones, and an ice core contains ice formed over a range of years. Cores aredrilled with handaugers (for shallow holes) or powered drills; they can reach depths of over two miles (3.2 km), and contain ice up to 800,000 years old.

The physical properties of the ice and of material trapped in it can be used to reconstruct the climate over the age range of the core. The proportions of different oxygen and hydrogenisotopes provide information aboutancient temperatures, and theair trapped in tiny bubbles can be analysed to determine the level of atmospheric gases such ascarbon dioxide. Sinceheat flow in a large ice sheet is very slow, the borehole temperature is another indicator of temperature in the past. This data can be combined to find theclimate model that best fits all the available data. (Full article...)
Image 21
Geologic time shown in a diagram called a geological clock, showing the relative lengths of the eons of Earth's history and noting major events

Thegeological history of Earth follows the major geological events in Earth's past based on thegeologic time scale, a system ofchronological measurement based on the study of the planet's rock layers (stratigraphy). Earth formedapproximately 4.54 billion years ago through accretion from thesolar nebula, a disk-shaped mass of dust and gas remaining from the formation of the Sun, which also formed the rest of theSolar System.

Initially, Earth was molten due to extremevolcanism and frequent collisions with other bodies. Eventually, the outer layer of the planet cooled to form a solidcrust when water began accumulating in the atmosphere. TheMoon formed soon afterwards, possibly as a result of the impact of a planetoid with Earth.Outgassing and volcanic activity produced the primordial atmosphere.Condensing water vapor, augmented by ice delivered fromasteroids,produced the oceans. However, in 2020, researchers reported thatsufficient water to fill the oceans may have always been onEarth since the beginning of the planet's formation. (Full article...)
Image 22

Isabel at peak intensity, northeast of theLeeward Islands, on September 11

Hurricane Isabel was aCategory 5 Atlantic hurricane that struck theeast coast of the United States in September 2003. The ninthnamed storm, fifth hurricane, and second major hurricane of theseason, Isabelformed in the easternAtlantic Ocean on September 6 from atropical wave. It moved northwestward through an area with light wind shea and warm waters, resulting in strengthening. Isabel reached peak winds of 165 mph (266 km/h) on September 11. After fluctuating in intensity for four days, Isabel gradually weakened and made landfall on theOuter Banks ofNorth Carolina, with winds of 105 mph (169 km/h) on September 18, or a Category 2 on theSaffir-Simpson scale. Isabel quickly weakened over land and becameextratropical over westernPennsylvania on the next day. On September 20, the extratropical remnants of Isabel were absorbed into another system overEastern Canada.

In North Carolina, the storm surge from Isabel washed out a portion ofHatteras Island to form what was unofficially known asIsabel Inlet. Damage was greatest along the Outer Banks, where thousands of homes were damaged or even destroyed. The worst of the effects of Isabel occurred inVirginia, especially in theHampton Roads area and along the shores of rivers as far west and north asRichmond andBaltimore. Virginia reported the most deaths and damage from the hurricane. About 64% of the damage and 69% of the deaths occurred in North Carolina and Virginia. Electric service was disrupted in areas of Virginia for several days, some more rural areas were without electricity for weeks, and local flooding caused thousands of dollars in damage. (Full article...)
Image 23

Bryce Canyon National Park (/braɪs/) is anational park of the United States located in southwesternUtah. The major feature of the park is Bryce Canyon, which despite its name, is not acanyon, but a collection of giant naturalamphitheaters along the eastern side of thePaunsaugunt Plateau. Bryce is distinctive due to geological structures calledhoodoos, formed byfrost weathering and stream erosion of the river and lake bedsedimentary rock. The red, orange, and white colors of the rocks provide spectacular views for park visitors. Bryce Canyon National Park is much smaller and sits at a much higher elevation than nearbyZion 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 ofGarfield County andKane County. (Full article...)
Image 24

A map of Earth as it appeared during the mid-Ediacaran,c. 600 Ma

TheEdiacaran (/ˌiːdiˈækərən,ˌɛdi-/EE-dee-AK-ər-ən,ED-ee-) is ageological period of theNeoproterozoic Era that spans 96 million years from the end of theCryogenian Period at 635Mya to the beginning of theCambrian Period at 538.8 Mya. It is the last period of theProterozoic Eon as well as the last of the so-called "Precambrian supereon", before the beginning of the subsequent Cambrian Period marks the start of thePhanerozoic Eon, where recognizablefossil evidence oflife becomes common.

The Ediacaran Period is named after theEdiacara Hills ofSouth Australia, wheretrace fossils of a diverse community of previously unrecognized lifeforms (later named theEdiacaran biota) were first discovered by geologistReg Sprigg in 1946. Its status as an official geological period was ratified in 2004 by theInternational Union of Geological Sciences (IUGS), making it the first new geological period declared in 120 years. Although the period tooknamesake from the Ediacara Hills in theNilpena Ediacara National Park, thetype section is actually located in the bed of the Enorama Creek within the Brachina Gorge in theIkara-Flinders Ranges National Park, at , approximately 55 km (34 mi) southeast of the Ediacara Hills fossil site. (Full article...)
Image 25

Map showing location ofepicenter of earthquake relative toAmbato; the bullseye is the epicenter; small blue lines are rivers

The1949 Ambato earthquake was a magnitude 6.4M_s earthquake that on August 5, 1949, struck Ecuador'sTungurahua Province southeast of its capitalAmbato and killed 5,050 people. The nearby villages ofGuano,Patate,Pelileo, andPillaro were destroyed, and the city of Ambato suffered heavy damage. The earthquake flattened buildings and subsequentlandslides caused damage throughout the Tungurahua,Chimborazo, andCotopaxi Provinces. It disrupted water mains and communication lines and opened a fissure into which the small town ofLibertad sank. Moderate shaking from the event extended as far away asQuito andGuayaquil.

Earthquakes in Ecuador stem from two major interrelated tectonic areas: thesubduction of theNazca plate under theSouth American plate and theAndean 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 theCarnegie Ridge. Strata of rock cracked as the earthquake ruptured the faults, sending out powerful shock waves. Today threats exist throughout the country from bothinterplate andintraplate seismicity. (Full article...)

Did you know(auto-generated)

... that thegeology of the Ellsworth Mountains was explored by geologists using motor toboggans in 1961?
... that geologistGilbert Wilson was the fifth Wilson at school, so he was known as "Quintus"?
... that the Danish geologistTove Birkelund received a gold medal for her early work on fossils ofScaphites in Greenland?
... that theApollo 12Solar Wind Spectrometer detected a gas-ionshockwave produced by the impact of the Apollo 13S-IVB stage on thelunar surface?
... thatKenshi Yonezu's song "Dune" describes his perception of a "desert-like atmosphere" on the video-sharing websiteNiconico?
... that theIowa Colored Cowboys played softball for audiences of over a thousand people, in an atmosphere similar to aHarlem Globetrotters show?
... thatFrederick 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?
... thatlife exists in every part of thebiosphere, from the deepest parts of the ocean to altitudes of up to 64 km (40 miles) in the atmosphere?

More did you know? -show different entries

...thatOjos del Salado(pictured) is the highest volcano on Earth?
...that theToronto Magnetic and Meteorological Observatory was originally built to study fluctuations inEarth's magnetic field?
...thatAtlantic hurricane reanalysis is an ongoing project within theNational Oceanic and Atmospheric Administration which seeks to correct and add new information about pastAtlantic tropical cyclones?
...thatRobert Case, aNational Weather Service meteorologist, dubbed the1991 Halloween Nor'easter "The Perfect Storm"?
...that the 1912Novarupta eruption ofMount Katmai was the largest of the 20th century?
... that the Northgeomagnetic pole is not the same as themagnetic North Pole, and that acompass points at neither?

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Image 1Bultfonteinite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 2Athunderstorm is a form ofsevere weather involvinglightning andthunder. Thunderstorms have had a lasting and powerful influence on mankind. Romans thought them to be battles waged byJupiter. Thunderstorms were associated with theThunderbird, held byNative Americans to be a servant of theGreat Spirit. (Credit: John Kerstholt.) (fromPortal:Earth sciences/Selected pictures)
Image 3Petrified wood, byDaniel Schwen (fromWikipedia:Featured pictures/Sciences/Geology)
Image 4Erg Chebbi (Arabic:عرج شبّي) is the soleSaharan erg inMorocco. It is 22 km long (North-South) and 5 km wide. Its dunes reach a maximum height of 150 meters. It is located roughly 40 kilometers south-east ofErfoud. The local center for tourists is the village ofMerzouga. (Credit:Rosa Cabecinhas and Alcino Cunha.) (fromPortal:Earth sciences/Selected pictures)
Image 5Platinum, byAlchemist-hp (fromWikipedia:Featured pictures/Sciences/Geology)
Image 6Hurricane Katrina was the third most powerful storm of the2005 Atlantic hurricane season. It first madelandfall as a Category 1hurricane just north ofMiami, Florida on August 25, 2005, then again onAugust 29 along the Central Gulf Coast nearBuras-Triumph, Louisiana as a Category 4 storm. This photograph of the eye of the hurricane was taken from aNOAA Hurricane Hunter aircraft on August 28, 2005. (Credit:NOAA.) (fromPortal:Earth sciences/Selected pictures)
Image 7Atmospheric gases scatter blue wavelengths of visible light more than other wavelengths, giving the Earth’s visible edge a blue halo. At higher and higher altitudes, the atmosphere becomes so thin that it essentially ceases to exist. Gradually, the atmospheric halo fades into the blackness of space. (Credit:NASA's Earth Observatory.) (fromPortal:Earth sciences/Selected pictures)
Image 8Gypsum, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 9Vanadinite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 10Creedite, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 11Hemimorphite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 12Azurite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 13This map shows the tracks of alltropical cyclones that formed worldwide from 1985 to 2005. The points show the locations of the storms at six-hourly intervals and use the color scheme shown on the right from theSaffir-Simpson Hurricane Scale. (Credit:Nilfanion.) (fromPortal:Earth sciences/Selected pictures)
Image 14Himalayan salt, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 15Thin section scan, byKallerna (fromWikipedia:Featured pictures/Sciences/Geology)
Image 16Wulfenite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 17Amethyst, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 18Northern shoremeadows ofSihlsee, anartificial lake nearEinsiedeln in theCanton of Schwyz,Switzerland. (Credit:Markus Bernet.) (fromPortal:Earth sciences/Selected pictures)
Image 19Mount Hood reflected inMirror Lake,Oregon. (Credit: Oregon's Mt. Hood Territory.) (fromPortal:Earth sciences/Selected pictures)
Image 20Smoky quartz, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 21Rhodochrosite, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 22Mount Redoubt eruption, by R. Clucas (USGS) (edited byJanke) (fromWikipedia:Featured pictures/Sciences/Geology)
Image 23Concretions, byMbz1 (fromWikipedia:Featured pictures/Sciences/Geology)
Image 24Cassiterite, byAlchemist-hp (fromWikipedia:Featured pictures/Sciences/Geology)
Image 25Incandescent Pahoeoe Fountain atShield volcano, by J.D. Griggs,USGS (fromWikipedia:Featured pictures/Sciences/Geology)
Image 26Azurite, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 27Glacier retreat is a type ofglacial motion in which more materialablates from its terminus of theglacier than is replenished by flow into that region. In this region of theBhutan-Himalaya, glacial lakes have been rapidly forming on the surface of thedebris-covered glaciers and researchers have found a strongcorrelation betweenincreasing temperatures and glacial retreat. (Credit:NASA &USGS.) (fromPortal:Earth sciences/Selected pictures)
Image 28Mohawkite, byAlchemist-hp (fromWikipedia:Featured pictures/Sciences/Geology)
Image 29TheRichat Structure is adepression in the country ofMauritania, almost 50 km (30 mi) across. It was originally thought to be the impact of ameteorite. Now it is thought to be a symmetricaluplift (circularanticline or dome) that has been exposed toerosion. In thisfalse-color photo,bedrock is brown, sand is yellow and white, vegetation is green, and saltysediments are blue. (Credit:Landsat 7.) (fromPortal:Earth sciences/Selected pictures)
Image 30Diatomaceous earth, byRichard Wheeler (fromWikipedia:Featured pictures/Sciences/Geology)
Image 31Cinnabar, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 32Pressure release ofgranite in theEnchanted Rock State Natural Area ofTexas,United States. The photo shows the geological exfoliation of granite dome rock. (Taken byWing-Chi Poon on 2nd April 2005.) (fromPortal:Earth sciences/Selected pictures)
Image 33An October 2002 eruption ofMount Etna, avolcano on theItalian island ofSicily, as seen from theInternational Space Station. Etna is the largest of Italy'sthree active volcanoes and one of the most active in the whole entire world. This eruption, one of Etna's most vigorous in years, was triggered by a series ofearthquakes.Ashfall was reported as far away asLibya, 600 km (373 mi) to the south. (Credit:Expedition 5 crew.) (fromPortal:Earth sciences/Selected pictures)
Image 34Specimen from a palaeontological site of Lebanon atPaleontology in Lebanon, byMila Zinkova (fromWikipedia:Featured pictures/Sciences/Geology)
Image 35Malachite, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 36Volcanictephra, byGodot13 (fromWikipedia:Featured pictures/Sciences/Geology)
Image 37Sand particles, bySiim (fromWikipedia:Featured pictures/Sciences/Geology)
Image 38Cirrus clouds are composed ofice crystals and shaped like hairlike filaments. They are formed at an altitudes above 5000 metres (16,500 feet). The streaks are made ofsnowflakes that are falling from the cloud and being caught by the high level winds. The streaks point in the direction of the wind and may appear straight giving the clouds the appearance of a comma (cirrus uncinus), or may by seem tangled, an indication of high levelturbulence. (Credit:Piccolo Namek.) (fromPortal:Earth sciences/Selected pictures)
Image 39Winter is one of the fourseasons of temperate zones.Meteorological winter is the season having the shortest days (which vary greatly according tolatitude) and the lowest temperatures. (Credit:Richard Fabi.) (fromPortal:Earth sciences/Selected pictures)
Image 40A true-color picture ofIreland, as seen from space, with theAtlantic Ocean to the west and theIrish Sea to the east. (fromPortal:Earth sciences/Selected pictures)
Image 41Aragonite, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 42The world's largestcompass rose, drawn on the desert floor atEdwards Air Force Base inCalifornia,United States. Painted on theplaya nearDryden Flight Research Center, it is inclined tomagnetic north and is used by pilots for calibratingheading indicators. (Credit:NASA.) (fromPortal:Earth sciences/Selected pictures)
Image 43Atacamite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 44Erosion of the bluff in Pacifica, bymbz1 (fromWikipedia:Featured pictures/Sciences/Geology)
Image 45Mimetite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 46Cerussite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 47Prehnite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 48Sulfur, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 49Wulfenite, byDidier Descouens (fromWikipedia:Featured pictures/Sciences/Geology)
Image 50Acanthite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 51Sarychev Peak atExplosive eruption, byNASA (fromWikipedia:Featured pictures/Sciences/Geology)
Image 52Tsunami in Thailand at2004 Indian Ocean earthquake and tsunami, by David Rydevik (fromWikipedia:Featured pictures/Sciences/Geology)
Image 53Crocoite, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 54Opal, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 55Dundasite byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 56Blairmorite, by Paul Glombick (edited byBammesk) (fromWikipedia:Featured pictures/Sciences/Geology)
Image 57Quartz, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 58Pyromorphite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 59Petrified log atPetrified Forest National Park, byMoondigger (fromWikipedia:Featured pictures/Sciences/Geology)
Image 60Sandstone, byMoondigger (fromWikipedia:Featured pictures/Sciences/Geology)
Image 61Baryte, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 62A 2002 eruption ofMount Etna, avolcano on theItalian island ofSicily, viewed from theInternational Space Station. (Credit: NASA, with image edits byUser:Darkone.) (fromPortal:Earth sciences/Selected pictures)
Image 63Pyrite, byJJ Harrison (fromWikipedia:Featured pictures/Sciences/Geology)
Image 64Aegirine, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 65Weathered rocks atJoshua Tree National Park, byMila Zinkova (fromWikipedia:Featured pictures/Sciences/Geology)
Image 66Antarctica, thecontinent surrounding theEarth'sSouth Pole, is thecoldest place on earth and is almost entirely covered byice. Antarctica was discovered in late January1820. Too cold and dry to support virtually any vascular plants, Antarctica's flora presently consists of around 250lichens, 100mosses, 25-30liverworts, and around 700 terrestrial and aquaticalgal species. (Credit:NASA.) (fromPortal:Earth sciences/Selected pictures)
Image 67Stellerite, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 68Astronauts aboard the Space Shuttle Discovery recorded this rarely seen phenomenon of the fullMoon partially obscured by theatmosphere of Earth. The image was recorded with an electronic still camera at 15:15:15 GMT, Dec. 21, 1999. (Credit:NASA.) (fromPortal:Earth sciences/Selected pictures)
Image 69Crystallinedolomite and magnesite, byDidier Descouens (fromWikipedia:Featured pictures/Sciences/Geology)
Image 70Celestine, byIifar (fromWikipedia:Featured pictures/Sciences/Geology)
Image 71Satellite image ofCyclone Gafilo, a powerfulCategory 5 tropical cyclone which struckMadagascar in March 2004, causing devastating damage. This was taken just before landfall, when the system was at its peak intensity about 333 km (207 mi) east of Madagascar, with sustained windspeed of 260 km/h (160 mph). At least 250 people were listed dead, with more missing, and 300,000 people were left homeless due to Gafilo. (Credit:Terra satellite,NASA.) (fromPortal:Earth sciences/Selected pictures)
Image 72Desert rose, byDidier Descouens (fromWikipedia:Featured pictures/Sciences/Geology)
Image 73Ant trapped in Balticamber, byBaltic-amber-beetle (edited byAmericanXplorer13) (fromWikipedia:Featured pictures/Sciences/Geology)
Image 742004 Indian Ocean Earthquake tsunami at2004 Indian Ocean earthquake and tsunami, by Vasily V. Titov,NOAA (edited byVeledan) (fromWikipedia:Featured pictures/Sciences/Geology)
Image 75Oceans cover almost three quarters (71%) of the surface of theEarth, and nearly half of the world's marine waters are over 3000 m deep. This global, interconnected body ofsalt water, called the World Ocean, is divided by thecontinents andarchipelagos into the following five bodies, from the largest to the smallest: thePacific Ocean, theAtlantic Ocean, theIndian Ocean, theSouthern Ocean, and theArctic Ocean. Official boundaries are defined by theInternational Hydrographic Organization. (Credit:Alexandre Van de Sande.) (fromPortal:Earth sciences/Selected pictures)

In the news

4 April 2025 –Democratic Republic of the Congo–United States relations: Lamuka opposition coalition spokesperson Prince Epenge criticizes the proposed minerals-for-security deal between theDemocratic Republic of Congo and theUnited States, describing it as a "sell-off."(Critical Threats)
2 April 2025 –Myanmar civil war: TheMyanmar government declares a temporaryceasefire with theNational Unity Government-in-exile and its various alliedethnic armed organizations to facilitaterelief efforts following theM_W 7.7 earthquake in the country several days ago. The ceasefire is expected to last until April 22.(DW)
1 April 2025 –2023–2025 Sundhnúkur eruptions: Seismic activity increases nearGrindavík,Iceland, with theIcelandic Meteorological Office reporting that avolcanic eruption has occurred and a earthquake is being registered. People visiting theBlue Lagoon are evacuated rapidly.(The Watchers)
1 April 2025 –Private spaceflight: SpaceX successfully launches fourhumans intoorbit over Earth’s poles for the first time for thehuman spaceflight missionFram2. The journey will last three to five days.(The New York Times)
31 March 2025 –2025 Myanmar earthquake: TheMyanmar government declares a period ofnational mourning inMyanmar to last until April 6 as the death toll from theearthquake last week rises to over 3,050 people.(AFP viaBarron's)
30 March 2025 –2025 Myanmar earthquake: Structures and infrastructure affected by the 2025 Myanmar earthquake

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