Earth Science, Geologic Time & Fossils, SUL-TRO
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
sulfide mineral, any member of a group of compounds of sulfur with one or more metals. Most of the sulfides are......
sulfosalt, any of an extensive group of minerals, mostly rare species, marked by some of the most complicated atomic......
sulfur (S), nonmetallic chemical element belonging to the oxygen group (Group 16 [VIa] of the periodic table),......
Kathryn Sullivan is an American oceanographer and astronaut, the first American woman to walk in space (1984).......
summer, warmest season of the year, between spring and autumn. In the Northern Hemisphere, it is usually defined......
sun dog, atmospheric optical phenomenon appearing in the sky as luminous spots 22° on each side of the Sun and......
supercontinent, large landmass that accounts for the vast majority of Earth’s land. Some researchers argue that......
law of superposition, a major principle of stratigraphy stating that within a sequence of layers of sedimentary......
surge, in meteorology, an atmospheric process that operates on oceans and inland waters whereby a change in atmospheric......
sussexite, white to straw-yellow borate mineral, basic manganese borate [MnBO2(OH)]. Magnesium replaces manganese......
svabite, arsenate mineral, calcium fluoride arsenate [Ca5(AsO4)3F], in the apatite group of phosphates. Typical......
Harold Ulrik Sverdrup was a Norwegian meteorologist and oceanographer known for his studies of the physics, chemistry,......
syenite, any of a class of intrusive igneous rocks essentially composed of an alkali feldspar and a ferromagnesian......
sylvanite, a gold and silver telluride mineral [(Au,Ag)Te2] in which the ratio of gold to silver atoms is commonly......
sylvite, halide mineral, potassium chloride (KCl), the chief source of potassium. It is rarer than halite (sodium......
George James Symons was a British meteorologist who strove to provide reliable observational data by imposing standards......
szaibelyite, mineral composed of basic magnesium borate [MgBo2(OH)], similar to the manganese mineral sussexite...
Although his formal education occurred between the ages of 8 and 10, plus four or five years at medical school,......
Tabulata, major division of extinct coral animals found as fossils in Ordovician to Jurassic marine rocks (488......
Tabūn, site of paleoanthropological excavations in a deep rock shelter located on the edge of Mount Carmel and......
tachylyte, glassy igneous rocks low in silica, such as basalt or diabase. Tachylytes are black with a pitchlike......
taeniodont, any member of an extinct suborder (Taeniodonta) of mammals that lived in North America throughout the......
taenite, nickel-iron mineral having a face-centred cubic structure and playing a major role in the crystallization......
Taiwan earthquake of 1999, earthquake that began at 1:47 am local time on Sept. 21, 1999, below an epicentre 93......
talc, common silicate mineral that is distinguished from almost all other minerals by its extreme softness (it......
Tangshan earthquake of 1976, earthquake on July 28, 1976, with a magnitude of 7.5, which nearly razed the Chinese......
tantalite, tantalum-rich variety of the mineral columbite (q.v.) with the chemical formula (Fe,Mn)(Ta,Nb)2O6. Tantalite......
tantalum (Ta), chemical element, bright, very hard, silver-gray metal of Group 5 (Vb) of the periodic table, characterized......
Tapinocephalus, extinct genus of therapsids, relatives of mammals, found as fossils in Permian rocks of South Africa......
Tarhun, ancient Anatolian weather god. His name appears in Hittite and Assyrian records (c. 1400–612 bc) and later......
Tasman Geosyncline, a linear trough in the Earth’s crust in which rocks that formed during the Paleozoic Era (542......
Taung child, the first discovered fossil of Australopithecus africanus. Exhumed by miners in South Africa in 1924,......
tectonics, scientific study of the deformation of the rocks that make up the Earth’s crust and the forces that......
tectosilicate, any member of a group of compounds with structures that have silicate tetrahedrons (each of which......
Pierre Teilhard de Chardin was a French philosopher and paleontologist known for his theory that man is evolving,......
Léon Teisserenc de Bort was a French meteorologist who discovered the stratosphere, thus paving the way for further......
tellurium (Te), semimetallic chemical element in the oxygen group (Group 16 [VIa] of the periodic table), closely......
temperature inversion, a reversal of the normal behaviour of temperature in the troposphere (the region of the......
temperature–humidity index (THI), combination of temperature and humidity that is a measure of the degree of discomfort......
tenorite, copper oxide mineral (CuO) found as gray-to-black metallic crystals as a sublimation product on lavas.......
tephrochronology, method of age determination that makes use of layers of ash (tephra). Tephra layers are excellent......
Henri-François-Émile Termier was a French geologist known for his studies of the stratigraphy (study of stratified......
Pierre-Marie Termier was a geologist known for his studies of the Eastern Alps. Termier was a professor at the......
Tertiary Period, former official interval of geologic time lasting from approximately 66 million to 2.6 million......
teschenite, coarse- to fine-grained, rather dark-coloured, intrusive igneous rock that occurs in sills (tabular......
Teshub, in the religions of Asia Minor, the Hurrian weather god, assimilated by the Hittites to their own weather......
Tetractinella, genus of extinct brachiopods (lamp shells) found as fossils in Triassic marine rocks (the Triassic......
tetradymite, a sulfide mineral of bismuth and tellurium (Bi2Te2S). It is commonly found in gold-quartz veins and......
Tetragraptus, genus of extinct graptolites (colonial animals related to the chordates) that occur as fossils in......
tetrahedrite, common sulfosalt mineral, an antimony sulfide of copper, iron, zinc, and silver [(Cu,Fe,Zn,Ag)12Sb4S13],......
texture, in rocks, the size, shape, and arrangement (or fabric) of the mineral grains and crystals. Also important......
Abraham Lincoln and Charles Darwin, two of the 19th century’s most enduring thinkers and figures, share more than......
thecodontian, archaic term formerly applied to any member of a group of primitive archosaurs (“ruling reptiles”)......
thenardite, any of a type of sodium sulfate mineral (Na2SO4) that has been deposited as an evaporation product......
Theodossia, genus of extinct brachiopods (lamp shells) the fossils of which are restricted to Early Devonian marine......
theralite, any member of a group of intrusive igneous rocks that contain labradorite (basic plagioclase feldspar),......
therapsid, any member of the Therapsida, a major clade of tetrapods that lived during Permian and Triassic time......
therizinosaur, group of theropod dinosaurs that lived during the Late Cretaceous (roughly 100 million to 66 million......
thermocline, oceanic water layer in which water temperature decreases rapidly with increasing depth. A widespread......
thermohaline circulation (THC), the component of general oceanic circulation controlled by horizontal differences......
thermonatrite, a carbonate mineral, hydrated sodium carbonate (Na2CO3·H2O), found near saline lakes as an evaporation......
thermosphere, region of increasing temperature in Earth’s atmosphere that is located above the mesosphere. The......
theropod, any member of the dinosaur subgroup Theropoda, which includes all the flesh-eating dinosaurs. Theropods......
David Thompson was an English explorer, geographer, and fur trader in the western parts of what are now Canada......
thorite, thorium silicate, ThSiO4, one of the most important thorium minerals. Almost always altered by hydration,......
Thrinaxodon, extinct genus of cynodont, a close mammal relative, found as fossils in continental deposits formed......
thunderstorm, a violent short-lived weather disturbance that is almost always associated with lightning, thunder,......
tidal bore, body of water that, during exceptionally high sea tides, rushes up some rivers and estuaries near a......
tide, any of the cyclic deformations of one astronomical body caused by the gravitational forces exerted by others.......
Tiktaalik roseae, an extinct fishlike aquatic animal that lived about 380–385 million years ago (during the earliest......
tillite, sedimentary rock that consists of consolidated masses of unweathered blocks (large, angular, detached......
tin (Sn), a chemical element belonging to the carbon family, Group 14 (IVa) of the periodic table. It is a soft,......
tincalconite, a borate mineral, hydrated sodium tetraborate (Na2B4O5(OH)4·3H2O), that is found in nature only as......
tinguaite, pale- to dark-green, very fine-grained igneous rock that may be considered the dike (tabular body injected......
TIROS, any of a series of U.S. meteorological satellites, the first of which was launched on April 1, 1960. The......
Titan, the largest moon of Saturn and the only moon in the solar system known to have clouds and a dense atmosphere.......
titanite, titanium and calcium silicate mineral, CaTiSiO4(O,OH,F), that, in a crystallized or compact form, makes......
Titanoboa, (Titanoboa cerrejonensis), extinct snake that lived during the Paleocene Epoch (66 million to 56 million......
titanosaur, (clade Titanosauria), diverse group of sauropod dinosaurs classified in the clade Titanosauria, which......
titanothere, any member of an extinct group of large-hoofed mammals that originated in Asia or North America during......
Tokyo-Yokohama earthquake of 1923, earthquake with a magnitude of 7.9 that struck the Tokyo-Yokohama metropolitan......
topaz, silicate mineral that is valued as a gemstone. It is believed that the topaz of modern mineralogists was......
torbernite, hydrated copper uranate phosphate mineral, Cu(UO2)2(PO4)2·8–12H2O, that is one of the principal uranium-bearing......
tornado, a small-diameter column of violently rotating air developed within a convective cloud and in contact with......
Tornoceras, extinct genus of cephalopods, forms related to the modern pearly nautilus. Tornoceras is a form that......
tourmaline, borosilicate mineral of complex and variable composition. Three types of tourmaline, distinguished......
Toxodon, extinct genus of mammals of the late Pliocene and the Pleistocene Epoch (about 3.6 million to 11,700 years......
trachyte, light-coloured, very fine-grained extrusive igneous rock that is composed chiefly of alkali feldspar......
transform fault, in geology and oceanography, a type of fault in which two tectonic plates slide past one another.......
Trepostomata, extinct order of bryozoans (moss animals) found as fossils in marine rocks of Ordovician to Triassic......
Triassic Period, in geologic time, the first period of the Mesozoic Era. It began 252 million years ago, at the......
Triconodon, genus of extinct mammals found in European deposits of the late Jurassic Period (about 161 million–146......
trilobite, any member of a group of extinct fossil arthropods easily recognized by their distinctive three-lobed,......
triphylite, common phosphate mineral, lithium iron phosphate (LiFePO4), usually forming bluish or grayish, glassy......
triplite, phosphate mineral, consisting of manganese, iron, magnesium, and calcium phosphate [(Mn, Fe, Mg, Ca)2PO4(F,OH)].......
Triton, U.S. nuclear-powered submarine that was the first vessel to circumnavigate the globe underwater. The Triton......
tritylodont, any member of a genus (Tritylodon) of extinct cynodont therapsids (mammal relatives) found as fossils......
Trochonema, genus of extinct gastropods (snails) found as fossils in rocks dating from the Ordovician Period to......
troctolite, coarse-grained, intrusive igneous rock that is composed almost entirely of olivine (often iron-rich)......
troilite, variety of the iron sulfide mineral pyrrhotite (q.v.) present in...