Portal:Earth sciences

Source: Wikipedia, the free encyclopedia.

Portal topics - (Random portal)

Activities
Culture
Geography
Health
History
Mathematics
Nature
People
Philosophy
Religion
Society
Technology

The Earth Sciences Portal

Earth seen from Moon
Earth seen from Moon

Earth science or geoscience includes all fields of natural science related to the planet Earth. This is a branch of science dealing with the physical, chemical, and biological complex constitutions and synergistic linkages of Earth's four spheres: the biosphere, hydrosphere/cryosphere, atmosphere, and geosphere (or lithosphere). Earth science can be considered to be a branch of planetary science but with a much older history. (Full article...)

Selected articles

  • Image 1 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...)
    mountain-building, and oceanic trench formation. (Full article...
    )
  • Image 2 The Berlin Archaeopteryx specimen (A. siemensii) Archaeopteryx (/ˌɑːrkiːˈɒptərɪks/ ⓘ; lit. 'ancient wing'), sometimes referred to by its German name, "Urvogel" (lit. Primeval Bird) is a genus of bird-like dinosaurs. The name derives from the ancient Greek ἀρχαῖος (archaîos), meaning "ancient", and πτέρυξ (ptéryx), meaning "feather" or "wing". Between the late 19th century and the early 21st century, Archaeopteryx was generally accepted by palaeontologists and popular reference books as the oldest known bird (member of the group Avialae). Older potential avialans have since been identified, including Anchiornis, Xiaotingia, Aurornis, and Baminornis. Archaeopteryx lived in the Late Jurassic around 150 million years ago, in what is now southern Germany, during a time when Europe was an archipelago of islands in a shallow warm tropical sea, much closer to the equator than it is now. Similar in size to a Eurasian magpie, with the largest individuals possibly attaining the size of a raven, the largest species of Archaeopteryx 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 small Mesozoic dinosaurs than with modern birds. In particular, they shared the following features with the dromaeosaurids and troodontids: jaws with sharp teeth, three fingers with claws, a long bony tail, hyperextensible second toes ("killing claw"), feathers (which also suggest warm-bloodedness), and various features of the skeleton. (Full article...)

    avialans have since been identified, including Anchiornis, Xiaotingia, Aurornis, and Baminornis.

    Archaeopteryx lived in the Late Jurassic around 150 million years ago, in what is now southern Germany, during a time when Europe was an archipelago of islands in a shallow warm tropical sea, much closer to the equator than it is now. Similar in size to a Eurasian magpie, with the largest individuals possibly attaining the size of a raven, the largest species of Archaeopteryx 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 small Mesozoic dinosaurs than with modern birds. In particular, they shared the following features with the dromaeosaurids and troodontids: jaws with sharp teeth, three fingers with claws, a long bony tail, hyperextensible second toes ("killing claw"), feathers (which also suggest warm-bloodedness), and various features of the skeleton. (Full article...
    )
  • Image 3 The 1867 Manhattan earthquake struck Riley County, Kansas, in the United States on April 24, 1867, at 20:22 UTC, or about 14:30 local time. The strongest earthquake to originate in the state, it measured 5.1 on a seismic scale that is based on an isoseismal map or the event's felt area. The earthquake's epicenter was near the town of Manhattan. The earthquake had a maximum perceived intensity of VII (Very strong) on the Mercalli intensity scale. It caused minor damage, reports of which were confined to Kansas, Iowa, and Missouri, according to the United States Geological Survey. Felt over an area of 200,000 square miles (520,000 km2), the earthquake reached the states of Indiana, Illinois, and possibly Ohio, though the latter reports have been questioned. (Full article...)
    Mercalli intensity scale. It caused minor damage, reports of which were confined to Kansas, Iowa, and Missouri, according to the United States Geological Survey. Felt over an area of 200,000 square miles (520,000 km2), the earthquake reached the states of Indiana, Illinois, and possibly Ohio, though the latter reports have been questioned. (Full article...
    )
  • Image 4 Map showing location of epicenter of earthquake relative to Ambato; the bullseye is the epicenter; small blue lines are rivers The 1949 Ambato earthquake was a magnitude 6.4 Ms earthquake that on August 5, 1949, struck Ecuador's Tungurahua Province southeast of its capital Ambato and killed 5,050 people. 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...)

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

    The 1949 Ambato earthquake was a magnitude 6.4 Ms earthquake that on August 5, 1949, struck Ecuador's Tungurahua Province southeast of its capital Ambato and killed 5,050 people. 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...)
  • Image 5 Old Faithful erupting at Yellowstone National Park A geyser (/ˈɡaɪzər/, UK: /ˈɡiːzər/) is a spring with an intermittent water discharge ejected turbulently and accompanied by steam. The formation of geysers is fairly rare and is caused by particular hydrogeological conditions that exist only in a few places on Earth. Generally, geyser field sites are located near active volcanic areas, and the geyser effect is due to the proximity of magma. 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...)
    volcanic areas, and the geyser effect is due to the proximity of magma. 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 Turquoise is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium, with the chemical formula CuAl6(PO4)4(OH)8·4H2O. It is rare and valuable in finer grades and has been prized as a gemstone for millennia due to its hue. The robin egg blue or sky blue color of the Persian turquoise mined near the modern city of Nishapur, Iran, has been used as a guiding reference for evaluating turquoise quality. (Full article...)
    opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium, with the chemical formula CuAl6(PO4)4(OH)8·4H2O. It is rare and valuable in finer grades and has been prized as a gemstone for millennia due to its hue.

    The robin egg blue or sky blue color of the Persian turquoise mined near the modern city of Nishapur, Iran, has been used as a guiding reference for evaluating turquoise quality. (Full article...
    )
  • Image 7 Lili near peak intensity in the Gulf of Mexico on October 2 Hurricane Lili was the second costliest, deadliest, and most intense hurricane of the 2002 Atlantic hurricane season, only surpassed by Hurricane 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 the Lesser Antilles as a tropical storm, then entered the Caribbean. As it moved west, the storm dissipated while being affected by wind shear south of Cuba, and regenerated when the vertical wind shear weakened. It turned to the northwest and strengthened up to category 2 strength on October 1. Lili made two landfalls in western Cuba later that day, and then entered the Gulf of Mexico. The hurricane rapidly strengthened on October 2, reaching Category 4 strength that afternoon. It weakened rapidly thereafter, and hit Louisiana 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...)

    landfalls in western Cuba later that day, and then entered the Gulf of Mexico. The hurricane rapidly strengthened on October 2, reaching Category 4 strength that afternoon. It weakened rapidly thereafter, and hit Louisiana 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 8 Grand Canyon of the Yellowstone Yellowstone National Park is a national park of the United States located in the northwest corner of Wyoming, with small portions extending into Montana and Idaho. It was established by the 42nd U.S. Congress through the Yellowstone National Park Protection Act and signed into law by President Ulysses S. Grant on March 1, 1872. Yellowstone was the first national park in the US, and is also widely understood to be the first national park in the world. The park is known for its wildlife and its many geothermal features, especially the Old Faithful geyser, one of its most popular. While it represents many types of biomes, the subalpine forest is the most abundant. It is part of the South Central Rockies forests ecoregion. While Native Americans have lived in the Yellowstone region for at least 11,000 years, aside from visits by mountain 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 the U.S. Department of the Interior, the first secretary of the interior to supervise the park being Columbus 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 the National Park Service, which had been created the previous year. Hundreds of structures have been built and are protected for their architectural and historical significance, and researchers have examined more than one thousand indigenous archaeological sites. (Full article...)

    subalpine forest is the most abundant. It is part of the South Central Rockies forests ecoregion.

    While Native Americans have lived in the Yellowstone region for at least 11,000 years, aside from visits by mountain 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 the U.S. Department of the Interior, the first secretary of the interior to supervise the park being Columbus 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 the National Park Service, which had been created the previous year. Hundreds of structures have been built and are protected for their architectural and historical significance, and researchers have examined more than one thousand indigenous archaeological sites. (Full article...
    )
  • Image 9 A map of Earth as it appeared during the mid-Ediacaran, c. 600 Ma The Ediacaran ( /ˌiːdiˈækərən, ˌɛdi-/ EE-dee-AK-ər-ən, ED-ee-) is a geological period of the Neoproterozoic Era that spans 96 million years from the end of the Cryogenian Period at 635 Mya to the beginning of the Cambrian Period at 538.8 Mya. It is the last period of the Proterozoic Eon as well as the last of the so-called "Precambrian supereon", before the beginning of the subsequent Cambrian Period marks the start of the Phanerozoic Eon, where recognizable fossil evidence of life becomes common. The Ediacaran Period is named after the Ediacara Hills of South Australia, where trace fossils of a diverse community of previously unrecognized lifeforms (later named the Ediacaran biota) were first discovered by geologist Reg Sprigg in 1946. Its status as an official geological period was ratified in 2004 by the International Union of Geological Sciences (IUGS), making it the first new geological period declared in 120 years. Although the period took namesake from the Ediacara Hills in the Nilpena Ediacara National Park, the type section is actually located in the bed of the Enorama Creek within the Brachina Gorge in the Ikara-Flinders Ranges National Park, at , approximately 55 km (34 mi) southeast of the Ediacara Hills fossil site. (Full article...)

    Ikara-Flinders Ranges National Park, at , approximately 55 km (34 mi) southeast of the Ediacara Hills fossil site. (Full article...
    )
  • Image 10 Life in the Ediacaran Period as imagined by researchers in 1980. The Ediacaran (/ˌiːdiˈækərən/; formerly Vendian) biota is a taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period (c. 635–538.8 Mya). These were enigmatic tubular and frond-shaped, mostly sessile, organisms. Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular 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 undergone evolutionary radiation in a proposed event called the Avalon explosion, 575 million years ago. This was after the Earth had thawed from the Cryogenian period's extensive glaciation. This biota largely disappeared with the rapid increase in biodiversity known as the Cambrian explosion. Most of the currently existing body plans of animals first appeared in the fossil record of the Cambrian 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...)
    sessile, organisms. Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular 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 undergone evolutionary radiation in a proposed event called the Avalon explosion, 575 million years ago. This was after the Earth had thawed from the Cryogenian period's extensive glaciation. This biota largely disappeared with the rapid increase in biodiversity known as the Cambrian explosion. Most of the currently existing body plans of animals first appeared in the fossil record of the Cambrian 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 Eruptions in the Lassen volcanic area in the last 70,000 years. Circle shows base of Mount Tehama. See timeline image. The Lassen volcanic area presents a geological record of sedimentation and volcanic activity in and around Lassen Volcanic National Park in Northern California, U.S. The park is located in the southernmost part of the Cascade Mountain Range in the Pacific Northwest region of the United States. Pacific Oceanic tectonic plates have plunged below the North American Plate in this part of North America for hundreds of millions of years. Heat and molten rock from these subducting plates has fed scores of volcanoes in California, Oregon, Washington and British Columbia over at least the past 30 million years, including these in the Lassen volcanic areas. Between 3 and 4 million years ago, volcanic-derived mud flows called lahars streamed down several major mountains that included nearby but now extinct Mount Yana and Mount Maidu to become the Tuscan Formation. Basaltic and later andesitic to dacitic flows of lava covered increasingly larger areas of this formation to eventually form the lava plateau upon which the park is situated. About 600,000 years ago, Mount Tehama started to rise as a stratovolcano in the southwestern corner of the park, eventually reaching an estimated 11,000 ft (3,400 m) in height. (Full article...)
    North American Plate in this part of North America for hundreds of millions of years. Heat and molten rock from these subducting plates has fed scores of volcanoes in California, Oregon, Washington and British Columbia over at least the past 30 million years, including these in the Lassen volcanic areas.

    Between 3 and 4 million years ago, volcanic-derived mud flows called lahars streamed down several major mountains that included nearby but now extinct Mount Yana and Mount Maidu to become the Tuscan Formation. Basaltic and later andesitic to dacitic flows of lava covered increasingly larger areas of this formation to eventually form the lava plateau upon which the park is situated. About 600,000 years ago, Mount Tehama started to rise as a stratovolcano in the southwestern corner of the park, eventually reaching an estimated 11,000 ft (3,400 m) in height. (Full article...
    )
  • Image 12 Panoramic winter view of Crater Lake from Rim Village Crater Lake (Klamath: Giiwas) is a volcanic crater lake in south-central Oregon in the Western United States. It is the main feature of Crater Lake National Park and is a tourist attraction for its deep blue color and water clarity. The lake partly fills a 2,148-foot-deep (655 m) caldera that was formed around 7,700 (± 150) years ago by the collapse of the volcano Mount Mazama. No rivers flow into or out of the lake; the evaporation is compensated for by rain and snowfall at a rate such that the total amount of water is replaced every 150 years. With a depth of 1,949 feet (594 m), the lake is the deepest in the United States. In the world, it ranks eleventh for maximum depth, as well as fifth for mean depth. Crater Lake features two small islands. Wizard Island, located near the western shore of the lake, is a cinder cone about 316 acres (128 hectares) in size. Phantom Ship, a natural rock pillar, is located near the southern shore. (Full article...)

    Panoramic winter view of Crater Lake from Rim Village

    Crater Lake (Klamath: Giiwas) is a volcanic crater lake in south-central Oregon in the Western United States. It is the main feature of Crater Lake National Park and is a tourist attraction for its deep blue color and water clarity. The lake partly fills a 2,148-foot-deep (655 m) caldera that was formed around 7,700 (± 150) years ago
    by the collapse of the volcano Mount Mazama. No rivers flow into or out of the lake; the evaporation is compensated for by rain and snowfall at a rate such that the total amount of water is replaced every 150 years. With a depth of 1,949 feet (594 m), the lake is the deepest in the United States. In the world, it ranks eleventh for maximum depth, as well as fifth for mean depth.

    Crater Lake features two small islands. Wizard Island, located near the western shore of the lake, is a cinder cone about 316 acres (128 hectares) in size. Phantom Ship, a natural rock pillar, is located near the southern shore. (Full article...)
  • Image 13 View of Mount Samalas along with Mount Rinjani In 1257, a catastrophic eruption occurred at Samalas, a volcano on the Indonesian island of Lombok. The event had a probable Volcanic Explosivity Index of 7, making it one of the largest volcanic eruptions during the Holocene epoch. It left behind a large caldera that contains Lake Segara Anak. Later volcanic activity created more volcanic centres in the caldera, including the Barujari cone, which remains active. The event created eruption columns reaching tens of kilometres into the atmosphere and pyroclastic flows that buried much of Lombok and crossed the sea to reach the neighbouring island of Sumbawa. The flows destroyed human habitations, including the city of Pamatan, which was the capital of a kingdom on Lombok. Ash from the eruption fell as far as 340 kilometres (210 mi) away in Java; the volcano deposited more than 10 cubic kilometres (2.4 cu mi) of rocks and ash. (Full article...)

    Volcanic Explosivity Index of 7, making it one of the largest volcanic eruptions during the Holocene epoch. It left behind a large caldera that contains Lake Segara Anak. Later volcanic activity created more volcanic centres in the caldera, including the Barujari cone, which remains active.

    The event created eruption columns reaching tens of kilometres into the atmosphere and pyroclastic flows that buried much of Lombok and crossed the sea to reach the neighbouring island of Sumbawa. The flows destroyed human habitations, including the city of Pamatan, which was the capital of a kingdom on Lombok. Ash from the eruption fell as far as 340 kilometres (210 mi) away in Java; the volcano deposited more than 10 cubic kilometres (2.4 cu mi) of rocks and ash. (Full article...
    )
  • Image 14 The inner planets. From left to right: Mercury, Venus, Earth, Mars and terrestrial dwarf planet, Ceres (sizes to scale) The geology of solar terrestrial planets mainly deals with the geological aspects of the four terrestrial planets of the Solar System – Mercury, Venus, Earth, and Mars – and one terrestrial dwarf planet: Ceres. Earth is the only terrestrial planet known to have an active hydrosphere. Terrestrial planets are substantially different from the giant planets, which might not have solid surfaces and are composed mostly of some combination of hydrogen, helium, and water existing in various physical states. Terrestrial planets have a compact, rocky surfaces, and Venus, Earth, and Mars each also has an atmosphere. Their size, radius, and density are all similar. (Full article...)
    The inner planets. From left to right: Mercury, Venus, Earth, Mars and terrestrial dwarf planet, Ceres (sizes to scale)

    The geology of solar terrestrial planets mainly deals with the geological aspects of the four terrestrial planets of the Solar System – Mercury, Venus, Earth, and Mars – and one terrestrial dwarf planet: Ceres. Earth is the only terrestrial planet known to have an active hydrosphere.

    Terrestrial planets are substantially different from the giant planets, which might not have solid surfaces and are composed mostly of some combination of hydrogen, helium, and water existing in various physical states. Terrestrial planets have a compact, rocky surfaces, and Venus, Earth, and Mars each also has an atmosphere. Their size, radius, and density are all similar. (Full article...)
  • Image 15 Yosemite Valley from Tunnel View Yosemite National Park (/joʊˈsɛmɪti/ yoh-SEM-ih-tee) is a national park of the United States in California. It is bordered on the southeast by Sierra National Forest and on the northwest by Stanislaus National Forest. The park is managed by the National Park Service and covers 759,620 acres (1,187 sq mi; 3,074 km2) in four counties – centered in Tuolumne and Mariposa, extending north and east to Mono and south to Madera. Designated a World Heritage Site in 1984, Yosemite is internationally recognized for its granite cliffs, waterfalls, clear streams, groves of giant sequoia, lakes, mountains, meadows, glaciers, and biological diversity. Almost 95 percent of the park is designated wilderness. Yosemite is one of the largest and least fragmented habitat blocks in the Sierra Nevada mountain range. Its geology is characterized by granite and remnants of older rock. About 10 million years ago, the Sierra Nevada was uplifted and tilted to form its unique slopes, which increased the steepness of stream and river beds, forming deep, narrow canyons. About one million years ago glaciers formed at higher elevations. They moved downslope, cutting and sculpting the U-shaped Yosemite Valley. (Full article...)

    Yosemite Valley from Tunnel View

    Yosemite National Park (/joʊˈsɛmɪti/ yoh-SEM-ih-tee) is a national park of the United States in California. It is bordered on the southeast by Sierra National Forest and on the northwest by Stanislaus National Forest. The park is managed by the National Park Service and covers 759,620 acres (1,187 sq mi; 3,074 km2) in four counties – centered in Tuolumne and Mariposa, extending north and east to Mono and south to Madera. Designated a World Heritage Site in 1984, Yosemite is internationally recognized for its granite cliffs, waterfalls, clear streams, groves of giant sequoia, lakes, mountains, meadows, glaciers, and biological diversity. Almost 95 percent of the park is designated wilderness. Yosemite is one of the largest and least fragmented habitat blocks in the Sierra Nevada mountain range.

    Its geology is characterized by granite and remnants of older rock. About 10 million years ago, the Sierra Nevada was uplifted and tilted to form its unique slopes, which increased the steepness of stream and river beds, forming deep, narrow canyons. About one million years ago glaciers formed at higher elevations. They moved downslope, cutting and sculpting the U-shaped Yosemite Valley. (Full article...)
  • Image 16 Mahameru (Semeru) above Mount Bromo, East Java. The geography of Indonesia is dominated by volcanoes that are formed due to subduction zones between the Eurasian plate and the Indo-Australian plate. Some of the volcanoes are notable for their eruptions, for instance, Krakatoa for its global effects in 1883, the Lake Toba Caldera for its supervolcanic eruption estimated to have occurred 74,000 years before present which was responsible for six years of volcanic winter, and Mount Tambora for the most violent eruption in recorded history in 1815. (Full article...)
    Lake Toba Caldera for its supervolcanic eruption estimated to have occurred 74,000 years before present which was responsible for six years of volcanic winter, and Mount Tambora for the most violent eruption in recorded history in 1815. (Full article...
    )
  • Image 17 Changes in surface air temperature over the past 50 years. The Arctic has warmed the most, and temperatures on land have generally increased more than sea surface temperatures. Present-day climate change includes both global warming—the ongoing increase in global average temperature—and its wider effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global temperatures is driven by human activities, especially fossil fuel burning since the Industrial Revolution. Fossil fuel use, deforestation, and some agricultural and industrial practices release greenhouse gases. These gases absorb some of the heat that the Earth radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary 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 large impact on the environment. Deserts are expanding, while heat waves and wildfires are becoming more common. Amplified warming in the Arctic has contributed to thawing permafrost, retreat of glaciers and sea ice decline. Higher temperatures are also causing more intense storms, droughts, and other weather extremes. Rapid environmental change in mountains, coral reefs, and the Arctic is forcing many species to relocate or become extinct. Even if efforts to minimize future warming are successful, some effects will continue for centuries. These include ocean heating, ocean acidification and sea level rise. (Full article...)

    Full article...
    )
  • Image 18 A scene in Uttarakhand's Valley of Flowers National Park. In contrast to the rain shadow region of Tirunelveli, the park receives ample orographic precipitation due to its location in a mountainous windward-facing region wedged between the Zanskars and the Greater Himalayas. The climate of India consists of a wide range of weather conditions across a vast geographic scale and varied topography. Based on the Köppen system, India encompasses a diverse array of climatic subtypes. These range from arid and semi-arid regions in the west to highland, sub-arctic, tundra, and ice cap climates in the northern Himalayan regions, varying with elevation. The northern lowlands experience subtropical conditions which become more temperate at higher altitudes, like the Sivalik Hills, or continental in some areas like Gulmarg. In contrast, much of the south and the east exhibit tropical climate conditions, which support lush rainforests in parts of these territories. Many regions have starkly different microclimates, making it one of the most climatically diverse countries in the world. The country's meteorological department follows four seasons with some local adjustments: winter (December to February), summer (March to May), monsoon or south-west monsoon (June to September) and post-monsoon or north-east monsoon (October to November). Some parts of the country with subtropical, temperate or continental climates also experience spring and autumn. (Full article...)
    continental in some areas like Gulmarg. In contrast, much of the south and the east exhibit tropical climate conditions, which support lush rainforests in parts of these territories. Many regions have starkly different microclimates, making it one of the most climatically diverse countries in the world. The country's meteorological department follows four seasons with some local adjustments: winter (December to February), summer (March to May), monsoon or south-west monsoon (June to September) and post-monsoon or north-east monsoon (October to November). Some parts of the country with subtropical, temperate or continental climates also experience spring and autumn. (Full article...
    )
  • Image 19 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. Its center is offshore, but the crater is named after the onshore community of Chicxulub Pueblo (not the larger coastal town of Chicxulub Puerto). It was formed slightly over 66 million years ago when an asteroid, about ten kilometers (six miles) in diameter, struck Earth. The crater is estimated to be 200 kilometers (120 miles) in diameter and 30 kilometers (19 miles) in depth. 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...)

    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. Its center is offshore, but the crater is named after the onshore community of Chicxulub Pueblo (not the larger coastal town of Chicxulub Puerto). It was formed slightly over 66 million years ago when an asteroid, about ten kilometers (six miles) in diameter, struck Earth. The crater is estimated to be 200 kilometers (120 miles) in diameter and 30 kilometers (19 miles) in depth. 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...)
  • Image 20 Radiocarbon dating helped verify the authenticity of the Dead Sea scrolls. Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon. The method was developed in the late 1940s at the University of Chicago by Willard Libby. It is based on the fact that radiocarbon (14 C) is constantly being created in the Earth's atmosphere by the interaction of cosmic rays with atmospheric nitrogen. The resulting 14 C combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire 14 C by eating the plants. When the animal or plant dies, it stops exchanging carbon with its environment, and thereafter the amount of 14 C it contains begins to decrease as the 14 C undergoes radioactive decay. Measuring the amount of 14 C in a sample from a dead plant or animal, such as a piece of wood or a fragment of bone, provides information that can be used to calculate when the animal or plant died. The older a sample is, the less 14 C there is to be detected, and because the half-life of 14 C (the period of time after which half of a given sample will have decayed) is about 5,730 years, the oldest dates that can be reliably measured by this process date to approximately 50,000 years ago, although special preparation methods occasionally make an accurate analysis of older samples possible. Libby received the Nobel Prize in Chemistry for his work in 1960. (Full article...)
    radioactive isotope of carbon.

    The method was developed in the late 1940s at the University of Chicago by Willard Libby. It is based on the fact that radiocarbon (14
    C    ) is constantly being created in the Earth's atmosphere by the interaction of cosmic rays with atmospheric nitrogen. The resulting 14
    C     combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire 14
    C     by eating the plants. When the animal or plant dies, it stops exchanging carbon with its environment, and thereafter the amount of 14
    C     it contains begins to decrease as the 14
    C     undergoes radioactive decay. Measuring the amount of 14
    C     in a sample from a dead plant or animal, such as a piece of wood or a fragment of bone, provides information that can be used to calculate when the animal or plant died. The older a sample is, the less 14
    C     there is to be detected, and because the half-life of 14
    C     (the period of time after which half of a given sample will have decayed) is about 5,730 years, the oldest dates that can be reliably measured by this process date to approximately 50,000 years ago, although special preparation methods occasionally make an accurate analysis of older samples possible. Libby received the Nobel Prize in Chemistry for his work in 1960. (Full article...
    )
  • Image 21 A map of Earth as it appeared 60 million years ago during the Paleocene Epoch, Selandian Age The Paleocene (IPA: /ˈpæli.əsiːn, -i.oʊ-, ˈpeɪli-/ PAL-ee-ə-seen, -⁠ee-oh-, PAY-lee-), or Palaeocene, is a geological epoch that lasted from about 66 to 56 Ma (million years ago). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek παλαιός palaiós meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by an asteroid impact (Chicxulub impact) and possibly volcanism (Deccan Traps), marked the beginning of the Paleocene and killed off 75% of species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. (Full article...)

    Chicxulub impact) and possibly volcanism (Deccan Traps), marked the beginning of the Paleocene and killed off 75% of species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. (Full article...
    )
  • Image 22 Gloria near peak intensity north of Hispaniola on September 24 Hurricane Gloria was a powerful tropical cyclone that caused significant damage along the East Coast of the United States and in Atlantic Canada during the 1985 Atlantic hurricane season. It was the first significant tropical cyclone to strike the northeastern United States since Hurricane Agnes in 1972 and the first major storm to affect New York City and Long Island directly since Hurricane Donna in 1960. Gloria was a Cape Verde hurricane originating from a tropical 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 the Lesser Antilles. During that time, the storm had moved generally westward, although it turned to the northwest due to a weakening of the ridge. Gloria quickly intensified on September 24, and the next day reached peak winds of 145 mph (233 km/h). The hurricane weakened before striking the Outer Banks of North Carolina on September 27. Later that day, Gloria made two subsequent landfalls on Long Island and across the coastline of western Connecticut, before becoming extratropical 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, the National Hurricane Center issued hurricane warnings at some point for the East 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 reduced storm 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...)

    extratropical 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, the National Hurricane Center issued hurricane warnings at some point for the East 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 reduced storm 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 23 The tornado outbreak of April 6–8, 2006, was a major tornado outbreak in the central and parts of the southern United States that began on April 6, 2006, in the Great Plains and continued until April 8 in South Carolina, with most of the activity on April 7. The hardest-hit region was Middle Tennessee, where several strong tornadoes devastated entire neighborhoods and left ten people dead. Some of the worst damage took place in Gallatin, Tennessee, and other communities north of Nashville 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 in Tennessee. 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 after another major outbreak on April 2. It was also considered by some to be the worst disaster event in Middle Tennessee since the 1998 tornado outbreak. (Full article...)
    The
    another major outbreak on April 2. It was also considered by some to be the worst disaster event in Middle Tennessee since the 1998 tornado outbreak. (Full article...
    )
  • Image 24 🜨 and Earth is the third planet from the Sun and the only astronomical object known to harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all of Earth's water is contained in its global ocean, covering 70.8% of Earth's crust. The remaining 29.2% of Earth's crust is land, most of which is located in the form of continental landmasses within Earth's land hemisphere. Most of Earth's land is at least somewhat humid and covered by vegetation, while large sheets of ice at Earth's polar deserts retain more water than Earth's groundwater, lakes, rivers, and atmospheric water combined. Earth's crust consists of slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Earth has a liquid outer core that generates a magnetosphere capable of deflecting most of the destructive solar winds and cosmic radiation. Earth has a dynamic atmosphere, which sustains Earth's surface conditions and protects it from most meteoroids and UV-light at entry. It has a composition of primarily nitrogen and oxygen. Water vapor is widely present in the atmosphere, forming clouds that cover most of the planet. The water vapor acts as a greenhouse gas and, together with other greenhouse gases in the atmosphere, particularly carbon dioxide (CO2), creates the conditions for both liquid surface water and water vapor to persist via the capturing of energy 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 the equatorial region receiving more sunlight than the polar regions) drive atmospheric and ocean currents, producing a global climate system with different climate regions, and a range of weather phenomena such as precipitation, allowing components such as nitrogen to cycle. (Full article...)
    climate regions, and a range of weather phenomena such as precipitation, allowing components such as nitrogen to cycle. (Full article...
    )
  • Image 25 Isabel at peak intensity, northeast of the Leeward Islands, on September 11 Hurricane Isabel was a Category 5 Atlantic hurricane that struck the east coast of the United States in September 2003. The ninth named storm, fifth hurricane, and second major hurricane of the season, Isabel formed in the eastern Atlantic Ocean on September 6 from a tropical wave. It moved northwestward through an area with light wind shear 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 the Outer Banks of North Carolina, with winds of 105 mph (169 km/h) on September 18, or a Category 2 on the Saffir-Simpson scale. Isabel quickly weakened over land and became extratropical over western Pennsylvania on the next day. On September 20, the extratropical remnants of Isabel were absorbed into another system over Eastern Canada. In North Carolina, the storm surge from Isabel washed out a portion of Hatteras Island to form what was unofficially known as Isabel 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 in Virginia, especially in the Hampton Roads area and along the shores of rivers as far west and north as Richmond and Baltimore. 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...)

    Saffir-Simpson scale. Isabel quickly weakened over land and became extratropical over western Pennsylvania on the next day. On September 20, the extratropical remnants of Isabel were absorbed into another system over Eastern Canada.

    In North Carolina, the storm surge from Isabel washed out a portion of Hatteras Island to form what was unofficially known as Isabel 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 in Virginia, especially in the Hampton Roads area and along the shores of rivers as far west and north as Richmond and Baltimore. 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...
    )

Did you know (auto-generated)

More did you know? - show different entries

Start a new article...

Selected images

In the news

6 July 2025 –
Five
methane gas exposure in a cave in northern Iraq during an operation to search for a fellow soldier's remains. (AP)
2 July 2025 – Quadrilateral Security Dialogue
minerals necessary for new technologies and reduce reliance on Chinese sources. (DW) (The Guardian)
15 June 2025 – 2025 Callao earthquake
A Mw 6.1 earthquake hits Lima, Peru, killing one person and injuring at least five others. (Agencia EFE)
10 June 2025 – Fossil fuel phase-out
The
nuclear power station in Suffolk, England, to reduce the country's reliance on fossil fuels. (AP) (Reuters)

Subcategories

Category puzzle
Category puzzle
Select [►] to view subcategories
Earth sciences
Earth
Earth scientists
Chronology
Earth sciences awards
Earth science conferences
Cryosphere
Earth and atmospheric sciences journals
Earth science conspiracy theories
Earth sciences textbooks
Earth system sciences
Environmental science
Geography
Geology
Geomathematics
History of Earth science
Earth observation
Earth sciences organizations
Palynology
Physical geography
Earth sciences publications
Soil science
Earth sciences software
Speleology
For a more comprehensive treatment of topics, see
Index of earth science articles
Atmosphere Hydrosphere Lithosphere
Biosphere Systems Others
Categories

Earth sciences • Atmospheric sciences • Ecology • Environmental science • Geography • Geology • Geomorphology • Geophysics • Glaciology • History of Earth science • Hydrology • Limnology • Oceanography • Paleoclimatology • Palynology • Physical geography • Soil science • Space science • Speleology 

Quality content

Featured articles
Climate change (More...)

Global warming
· Rachel Carson · Retreat of glaciers since 1850

Earthquakes (More...)

1949 Ambato earthquake · 1968 Illinois earthquake · 1980 eruption of Mount St. Helens · 1997 Qayen earthquake · 2002 Bou'in-Zahra earthquake · 2005 Qeshm earthquake · 2007–2008 Nazko earthquakes

Volcanoes (More...)

1980 eruption of Mount St. Helens · 2007–2008 Nazko earthquakes · Amchitka · Armero tragedy · Calabozos · Cerro Azul (Chile volcano) · Craters of the Moon National Monument and Preserve · David A. Johnston · Geology of the Lassen volcanic area ·

Loihi Seamount
· Mauna Kea · Mauna Loa · Metacomet Ridge · Mono–Inyo Craters · Mount Cayley volcanic field · Mount St. Helens · Mount Tambora · Nevado del Ruiz · Surtsey · The Volcano (British Columbia) · Upper and Lower Table Rock · Volcano (South Park) · Yellowstone National Park

Other geology (More...)

Mary Anning · Archaea · Archaeopteryx · Cerro Azul (Chile volcano) · Bryce Canyon National Park · Calabozos · Chicxulub crater · Cretaceous–Paleogene extinction event · Charles Darwin · Earth · Ediacaran biota · Geology of the Bryce Canyon area · Geology of the Capitol Reef area · Geology of the Death Valley area · Geology of the Grand Canyon area · Geology of the Lassen volcanic area · Geology of the Zion and Kolob canyons area ·

Global warming
· Iridium · Oil shale · The Volcano (British Columbia) · Toronto Magnetic and Meteorological Observatory ·
Volcanology of Io
· Yellowstone National Park

Geography (More...)

Antarctica · Australia · Bryce Canyon National Park · Carlsbad Caverns National Park · Craters of the Moon National Monument and Preserve · Death Valley National Park · Geography of India · Geography of Ireland ·

National parks of England and Wales
· Niagara Falls · Rondane National Park · Shoshone National Forest · Yellowstone National Park · Yosemite National Park · Zion National Park

Featured topics

1941 Atlantic hurricane season · 1991 Atlantic hurricane season · 1995 Pacific hurricane season · 1998 Pacific hurricane season · 2002 Atlantic hurricane season · 2003 Atlantic hurricane season · Category 5 Pacific hurricanes · Hurricane Isabel · Lists of Florida hurricanes · Lists of North Carolina hurricanes

·
Retired Pacific hurricanes
Featured pictures
Views of Earth from space and satellites · Geology
Featured lists

WikiProjects

Things you can do

  • Edit an Earth sciences article
Whether you are an expert or a novice, be
editing it. If you're not sure how to do it, practice in the sandbox
.
  • Add new articles:

Associated Wikimedia

The following Wikimedia Foundation sister projects provide more on this subject:

Discover Wikipedia using portals
Retrieved from "https://en.wikipedia.org/w/index.php?title=Portal:Earth_sciences&oldid=1290155367"