Earth Science, Geologic Time & Fossils, VOL-ZIR
Planet Earth has billions of years of history, from the time when it was an inhospitable ball of hot magma to when its surface stabilized into a variety of diverse zones capable of supporting many life-forms. Many are the species that lived through the various geologic eras and left a trace of their existence in the fossils that we study today. But Earth is never done settling, as we can see from the earthquakes, tsunamis, volcanic eruptions, and other phenomena manifested in Earth’s crust, oceans, and atmosphere.
Earth Science, Geologic Time & Fossils Encyclopedia Articles By Title
volcanic glass
volcanic glass, any glassy rock formed from lava or magma that has a chemical composition close to that of granite......
volcanic winter
volcanic winter, cooling at Earth’s surface resulting from the deposition of massive amounts of volcanic ash and......
volcanism
volcanism, any of various processes and phenomena associated with the surficial discharge of molten rock, pyroclastic......
volcano
volcano, vent in the crust of Earth or another planet or satellite, from which issue eruptions of molten rock,......
- Introduction
- Lava, Gas, Hazards
- Ash Falls, Eruptions, Magma
- Secondary Damage, Eruptions, Hazards
- Eruptions, Types, Magma
- Pinatubo, Philippines, 1991
- Hawaii, Mauna Loa, 1984
- Vesuvius, Tambora, Krakatoa, Pelee
- Forecasting, Warning, Monitoring
- Eruptions, Cone, Magma
- Calderas, Magma, Eruptions
- Lava Domes, Magma, Eruptions
- Eruptions, Magma, Structure
- Hot Springs, Geysers, Magma
- Plate Boundaries, Magma, Eruptions
- Rift, Magma, Eruptions
- Magma, Eruptions, Geothermal
volcanology
volcanology, discipline of the geologic sciences that is concerned with all aspects of volcanic phenomena. Volcanology......
Voltzia
Voltzia, a genus of fossil cone-bearing plants dating to the Early Triassic epoch (beginning 251 million years......
Vredefort Dome
Vredefort Dome, the largest known meteorite impact structure on Earth. The Vredefort Dome is an area of raised......
Väisälä, Yrjö
Yrjö Väisälä was a Finnish meteorologist and astronomer noted for developing meteorological measuring methods and......
Wabar Craters
Wabar Craters, group of meteorite craters discovered in 1932 in the Rubʿ al-Khalī desert of Saudi Arabia. The largest......
Waksman, Selman Abraham
Selman Abraham Waksman was a Ukrainian-born American biochemist who was one of the world’s foremost authorities......
Water cycle
Water cycle, cycle that involves the continuous circulation of water in the Earth-atmosphere system. Of the many......
water mass
water mass, body of ocean water with a distinctive narrow range of temperature and salinity and a particular density......
water table
water table, upper level of an underground surface in which the soil or rocks are permanently saturated with water.......
waterspout
waterspout, a small-diameter column of rapidly swirling air in contact with a water surface. Waterspouts are almost......
wave
wave, a ridge or swell on the surface of a body of water, normally having a forward motion distinct from the oscillatory......
wavellite
wavellite, hydrated aluminum phosphate [Al3(PO4)2(OH)3·5H2O], a common phosphate mineral that typically occurs......
Weather
Weather, state of the atmosphere at a particular place during a short period of time. It involves such atmospheric......
Weather bureau
Weather bureau, agency established by many countries to observe and report the weather and to issue weather forecasts......
Weather forecasting
Weather forecasting, the prediction of the weather through application of the principles of physics, supplemented......
Weather map
Weather map, any map or chart that shows the meteorological elements at a given time over an extended area. The......
weather modification
weather modification, the deliberate or the inadvertent alternation of atmospheric conditions by human activity,......
Weather satellite
Weather satellite, any of a class of Earth satellites designed to monitor meteorological conditions (see Earth...
weathering
weathering, disintegration or alteration of rock in its natural or original position at or near the Earth’s surface......
Wedekindellina
Wedekindellina, genus of fusulinid foraminiferans, an extinct group of protozoans that possessed a hard shell of......
Wegener, Alfred
Alfred Wegener was a German meteorologist and geophysicist who formulated the first complete statement of the continental......
Wei Yuan
Wei Yuan was a historian and geographer of the Qing dynasty (1644–1911/12). Wei was a leader in the Statecraft......
Werner, Abraham Gottlob
Abraham Gottlob Werner was a German geologist who founded the Neptunist school, which proclaimed the aqueous origin......
West Greenland Current
West Greenland Current, cool flow of water proceeding northward along the west coast of Greenland. See Greenland...
Wet equatorial climate
Wet equatorial climate, major climate type of the Köppen classification characterized by consistently high temperatures......
What causes a drought?
Droughts occur when evaporation and transpiration rates consistently exceed precipitation over an extended period......
What causes a rainbow?
What causes a rainbow?, The formation of a rainbow begins with the refraction of sunlight as it enters a raindrop.......
What Causes a Volcano to Erupt?
Volcanic eruptions are among the most stunning phenomena in the natural world. Volcanoes erupt because of the way......
What causes acid rain?
The main contributors to acid rain are sulfur dioxide (SO2) and nitrogen oxides (NOx; the combination of NO and......
What causes soil erosion?
Soil erosion, like rock erosion, is caused by the movement of water and wind, and glaciers. Since soil (whether......
What Causes the Northern and Southern Lights?
The auroras—the aurora borealis (or northern lights) in the Northern Hemisphere, and the aurora australis (the......
What causes tides in the ccean?
The main cause of tides in the ocean are the gravitational forces exerted by the Moon and the Sun on Earth. When......
What Happened to the Dinosaurs?
One day 66 million years ago, an asteroid the size of a mountain struck near the Yucatán Peninsula with an explosive......
What Happens to Earth If the Amazon Rainforest Is Completely Burned?
Metaphorically speaking, the vast tropical rainforest in South America’s Amazon River basin is often called the......
What Is an Aftershock?
Earth is an active place full of storms, fast-moving river and ocean currents, volcanoes, and earthquakes. Continents......
What Is Earth’s Velocity?
Earth has several velocities. There is the velocity with which it rotates on its axis. A point on Earth’s Equator......
What Is Known (and Not Known) About Contrails
Contrail is short for “condensation trail.” A condensation trail is a streamer of cloud sometimes observed behind......
What Is Relative Humidity?
Relativity, in our understanding, depends on the value of one thing compared to another. For example, a mouse is......
What is the coldest temperature ever recorded on Earth?
Antarctica holds the record for the lowest temperature ever recorded on Earth. At Vostok Station, a Russian research......
What Is the Difference Between a Meteotsunami, a Seiche, and a Storm Surge?
A meteotsunami is a large sea wave, with a wave height of two metres (about 6 feet) or more. Unlike seismic tsunamis,......
What is the difference between archaeology and paleontology?
Imagine a person who studies the past. This person travels the world, leads excavations, and carefully unearths......
What Is the Difference Between El Niño and La Niña?
Every few years the phenomenon known as El Niño dominates the headlines. In other years its climatic alter ego......
What Makes a Wave Go Rogue?
Many a tall tale has been inspired by the world’s oceans, from stories of mysterious sea monsters to legends about......
What Was the Little Ice Age?
When most people think of ice ages, or “glacial ages,” they often envision cavemen, woolly mammoths, and vast plains......
What would happen if Earth stopped rotating?
A sudden halt in Earth’s rotation would cause severe and widespread disruption to the planet’s physical structure,......
What’s the Difference Between Global Warming and Climate Change?
People often confuse the concepts of global warming and climate change, and it doesn’t help that media companies......
What’s the Difference Between Weather and Climate?
Adding confusion to the politics of climate change and global warming in the press is the assumption that the terms......
whirlpool
whirlpool, rotary oceanic current, a large-scale eddy that is produced by the interaction of rising and falling......
whirlwind
whirlwind, a small-diameter columnar vortex of rapidly swirling air. A broad spectrum of vortices occurs in the......
Why Are Clouds White?
Clouds appear white because of the nature of the incident light and the way this light is scattered by them. Sunlight......
Why are higher elevations colder?
Higher elevations are colder primarily due to the decrease in atmospheric pressure that results from the expansion......
Why Are Hurricanes Rare in Hawaii?
One would think that a group of tropical islands that lie just south of the Tropic of Cancer would be a prime target......
Why Are Pterodactyls Not Dinosaurs?
No matter how much you like pterodactyls, you’ll want to think twice before telling someone that they’re your favorite......
Why are rainbows curved?
Rainbows are curved because of the way sunlight interacts with water droplets in the atmosphere. When sunlight......
Why are rip currents dangerous?
Rip currents are dangerous primarily because they are often more powerful than they initially seem and move quickly,......
Why do stars twinkle?
Light emitted from stars does not actually twinkle but only appears to twinkle when viewed from Earth. As starlight......
Why do we have seasons?
Seasons occur due to the tilt of Earth’s axis, which is approximately 23.5°. Because of this tilt, each hemisphere......
Why Does -saur Appear So Often in Dinosaur Names?
The suffix -saurus, which appears at the end of the scientific names of various dinosaurs (and in shortened form......
Why Does a Mushroom Cloud Look Like a Mushroom?
A mushroom cloud is the iconic and terrifying result of a thermonuclear explosion, but actually a mushroom cloud......
Why does the Earth rotate?
The Earth rotates because of the conservation of angular momentum acquired from the rotation of the solar nebula,......
Why Does the Tropic of Cancer’s Location on Earth Move Over Time?
The Tropic of Cancer is a line of latitude approximately 23°27′ north of Earth’s Equator. This latitude corresponds......
Why Is Earth’s Axis Tilted?
Earth rotates eastward, a counterclockwise motion when viewed from a point above the North Pole. The hypothetical......
Why Is Predicting the Weather So Difficult for Meteorologists?
Simply stated, predicting the future is hard work, and meteorologists should never be expected to get things exactly......
Why is summer warmer than winter?
The temperature people feel outside is largely based on the absorption of radiant energy from the Sun. Differing......
Why Is the Ocean Salty?
“Water, water everywhere,/ Nor any drop to drink.” This famous line, spoken by the lost sailor in Samuel Taylor......
Why Is There Fresh and Salt Water on Earth?
Rain and other forms of precipitation fall on our planet as slightly acidic fresh water. As some of this water......
Wilkins Ice Shelf
Wilkins Ice Shelf, a large body of floating ice covering the greater part of Wilkins Sound off the western coast......
willemite
willemite, white or greenish yellow silicate mineral, zinc silicate, Zn2SiO4, that is found as crystals, grains,......
Wilson, J. Tuzo
J. Tuzo Wilson was a Canadian geologist and geophysicist who established global patterns of faulting and the structure......
Wind
Wind, in climatology, the movement of air relative to the surface of the Earth. Winds play a significant role in......
Wind chill
Wind chill, a measure of the rate of heat loss from skin that is exposed to the air. It is based on the fact that,......
Wind shear
Wind shear, rapid change in wind velocity or direction. A very narrow zone of abrupt velocity change is known as......
Windstorm
Windstorm, a wind that is strong enough to cause at least light damage to trees and buildings and may or may not......
Winter
Winter, coldest season of the year, between autumn and spring; the name comes from an old Germanic word that means......
witherite
witherite, a carbonate mineral, barium carbonate (BaCO3), that is, with the exception of barite, the most common......
Witwatersrand System
Witwatersrand System, major division of Precambrian rocks in South Africa (the Precambrian began about 3.8 billion......
Wolf Creek Crater
Wolf Creek Crater, huge meteorite crater 65 miles (105 km) south of Halls Creek, Western Australia. The crater......
wolframite
wolframite, chief ore of tungsten, commonly associated with tin ore in and around granite. Such occurrences include......
woolly rhinoceros
woolly rhinoceros, (genus Coelodonta), either of two extinct species of rhinoceros found in fossil deposits of......
World Geography Quiz
Test your knowledge of the countries of the world with Britannica’s Geography Quiz! Identify countries on a world......
World Meteorological Organization
World Meteorological Organization (WMO), specialized agency of the United Nations (UN) created to promote the establishment......
Worthenia
Worthenia, genus of extinct gastropods (snails) preserved as common fossils in rocks of Devonian to Triassic age......
wulfenite
wulfenite, lead molybdate, PbMoO4, a minor source of molybdenum and the second most common molybdenum mineral.......
wurtzite
wurtzite, a zinc sulfide mineral that occurs typically in Potosí, Bolivia; Butte, Mont.; and Goldfield, Nev. It......
Wüst, Georg
Georg Wüst was a German oceanographer who, by collecting and analyzing many systematic observations, developed......
Xenacanthus
Xenacanthus, long-surviving but now extinct genus of freshwater sharks. Xenacanthus survived from the end of the......
xenolith
xenolith, rock fragment within an intrusive igneous body that is unrelated to the igneous body itself. Xenoliths,......
xenotime
xenotime, widely distributed phosphate mineral, yttrium phosphate (YPO4), though large proportions of erbium commonly......
Yonaguni Monument
Yonaguni Monument, underwater rock structure that was discovered in the mid-1980s near Yonaguni Island, Japan.......
Younger Dryas
Younger Dryas, cool period between roughly 12,900 and 11,600 years ago that disrupted the prevailing warming trend......
zeolite
zeolite, any member of a family of hydrated aluminosilicate minerals that contain alkali and alkaline-earth metals.......
zeolite facies
zeolite facies, one of the major divisions of the mineral facies classification of metamorphic rocks, the rocks......
Zhang Heng
Zhang Heng was a Chinese mathematician, astronomer, and geographer. His seismoscope for registering earthquakes......
zinc
zinc (Zn), chemical element, a low-melting metal of Group 12 (IIb, or zinc group) of the periodic table, that is......
zincite
zincite, mineral consisting of zinc oxide (ZnO), usually found in platy or granular masses. Its blood-red colour......
zircon
zircon, silicate mineral, zirconium silicate, ZrSiO4, the principal source of zirconium. Zircon is widespread as......