Geology Geology :"The capital fact to note is that petroleum was born in the depths of the earth, and it is only there that we must seek its origin." ( Dmitri Mendeleev, 1877) ...more on Wikipedia about "Abiogenic petroleum origin"
Acritarchs are small organic structures found as fossils. In general, any small, non- acid soluble (i.e. non carbonate, non-silicate) organic structure that can not otherwise be accounted for is an acritarch. Most acritarchs are surely remains of single celled lifeforms. They are found in sedimentary rocks from the present back into the Precambrian. They are easily isolated from limestones with hydrochloric acid, and can also be isolated from silica rich rocks using hydrofluoric acid. They are excellent candidates for index fossils to be used for formation dating in the Palaeozoic and when other fossils are not available. They are also useful for palaeoenvironmental interpretation. Acritarchs include the remains of several quite different kinds of organisms including bacteria and dinoflagellates. The nature of the creatures associated with older acritarchs is generally not clear, though many are probably related to unicellular marine algae. ...more on Wikipedia about "Acritarch"
An active fault is a fault which has had displacement or seismic activity during the geologically recent period. In the United States, an active fault is generally defined as a fault which displaced earth materials during the Holocene (Recent) Epoch (during the last 11,000 or so years before present). Active faults are the most common sources of earthquakes and tectonic movements. In California, the well known San Andreas Fault is the most active fault in that state and the source of the largest earthquakes historically and during the Holocene. ...more on Wikipedia about "Active fault"
The age of the Earth is estimated to be 4.55 billion (4.55 × 109) years, based on detailed scientific evidence. This estimate represents a compromise between the oldest known terrestrial minerals – small crystals of zircon from the Jack hills of Western Australia – and astronomers' and planetologists' estimates of the age of the solar system. The radiometric age dating evidence from the zircons further confirms that the Earth is at least 4.404 billion years old. Comparing the mass and luminosity of the Sun to the multitudes of other stars, it appears that the solar system can not be much older than those rocks. Ca-Al-rich inclusions – the oldest known solid constituents within meteorites which are formed within the solar system – are 4.567 billion years old, giving an age for the solar system and an upper limit for the age of the Earth. It is assumed that the accretion of the Earth began soon after the formation of the Ca-Al-rich inclusions and the meteorites. Since the accretion time of the Earth is not exactly known yet and the predictions from different accretion models vary between several millions up to about one hundred million years, the exact age of the Earth is difficult to define. ...more on Wikipedia about "Age of the Earth"
An agrogeologist is a scientist trained in agrogeology. Agrogeologists study the origins of agrominerals and their applications. ...more on Wikipedia about "Agrogeologist"
Agrogeology is the study of minerals of importance to farming and horticulture, especially with regards to soil fertility and to the inorganic, non-nitrogenous components of fertilizers. These minerals are usually essential plant nutrients and are referred to as agrominerals. ...more on Wikipedia about "Agrogeology"
Agrominerals are minerals of importance to agriculture and horticulture, and are usually essential plant nutrients. ...more on Wikipedia about "Agrominerals"
The Andean-Saharan glaciation was from 450 mya to 420 mya, during most of the Silurian period and the beginning of the Devonian period. ...more on Wikipedia about "Andean-Saharan"
In the Mesozoic, Appalachia was a land area which is now an eastern part of the USA, separated from Laramidia by the Western Interior Seaway, which shrank and became the Pierre Seaway and finally dried up. Laramidia was roughly what is now the western cordillera area of the USA and Canada. ...more on Wikipedia about "Appalachia (Mesozoic)"
In geology, aseismic creep is measurable surface displacement along a fault in the absence of notable earthquakes. Perhaps the best known example is along the Calaveras fault in Hollister, California. Streets crossing the fault in Hollister show significant offset and several houses sitting atop the fault are notably twisted (yet inhabitable). The city attracts geologist and geology students almost weekly. There is also significant aseismic creep along the Hayward fault in and near Hayward, California. ...more on Wikipedia about "Aseismic creep"
An assise (from the Fr., derived from Latin assidere, "to sit beside"), is a geological term for two or more beds or strata of rock united by the occurrence of the same characteristic species or genera. ...more on Wikipedia about "Assise"
The asthenosphere (from an invented Greek a + 'sthenos "without strength") is the region of the Earth between 100-200 km below the surface — but perhaps extending as deep as 400 km — that is the weak or "soft" zone in the upper mantle. It lies just below the lithosphere, which is involved in plate movements and isostatic adjustments. In spite of its heat, pressures keep it plastic, and it has a relatively low density. Seismic waves, the speed of which decrease with the softness of a medium, pass relatively slowly though the asthenosphere, the cue that originally alerted seismologists to its presence; thus it has been given the name low-velocity zone. ...more on Wikipedia about "Asthenosphere"
Bacterial oxidation is a bio-hydrometallurgical process developed for pre- cyanidation treatment of refractory gold ores or concentrates. The bacterial culture is a mixed culture of Thiobacillus ferrooxidans, Thiobacillus thiooxidans and Leptospirillum ferrooxidans. The bacterial oxidation process comprises contacting refractory sulfide ROM ore or concentrate with a strain of the bacterial culture for a suitable treatment period under an optimum operating environment. The bacteria oxidise the sulfide minerals, thus liberating the occluded gold for subsequent recovery via cyanidation. ...more on Wikipedia about "Bacterial oxidation"
:This article is about the type of terrain. Note that in the late 19th century, the term "badlands" was extended to refer to urban regions of vice and crime. For the film, see Badlands (film). ...more on Wikipedia about "Badlands"
Basement rock usually refers to the thick foundation of ancient, and oldest metamorphic and igneous rock that forms the crust of continents, often granite. Basement rock is contrasted to overlying sedimentary rocks which are laid down on top of the basement rocks after the continent was formed, such as sandstone and limestone. The sedimentary rocks which may be deposited on top of the basement usually form a relatively thin veneer, which however may be several miles thick - 3 miles or more. The basement rocks of the crust can be 20-30 miles thick, or more. The basement rocks can be located under layers of sedimentary rock, or be visible at the surface. Basement rock is visible at the bottom of the Grand Canyon, consisting of 1.7-2 billion year old granite and schist, the Vishnu schist and Zoroaster granite. The vishnu schist is believed to be highly metamorphosed igneous rocks and shale, from basalt, mud and clay laid from volcanic eruptions, and the granite is the result of magma intrusions into the vishnu schist. An extensive cross section of sedimentary rocks laid down on top of it through the ages is also visible as well. ...more on Wikipedia about "Basement rock"
:This article is about the type of rock. Bedrock is also the name of the town in which The Flintstones lived. ...more on Wikipedia about "Bedrock"
In geology, Bernician Series was a term proposed by S. P. Woodward in 1856 (Manual of Mollusca, p. 409) for the lower portion of the Carboniferous System, below the Millstone Grit. The name was suggested by that of the ancient province of Bernicia on the Anglo-Scottish borderland. It is practically equivalent to the Dinantien of A. de Lapparent and Munier-Chalmas (1893). In 1875 G. Tates Calcareous and Carbonaceous groups of the Carboniferous Limestone series of Northumberland were united by Professor Lebour into a single series, to which he applied the name Bernician; but later he speaks of the whole of the Carbonilerous rocks of Northumberland and its borders as of the Bernician type, which is the most satisfactory way in which the term may now be used (Report of 1/fe Brit. Sub-committee on Classification and Nomenclature, 2nd ed., Cambridge, 1888). Demetian was the corresponding designation proposed by Woodward for the Upper Carbonife-rous rocks. ...more on Wikipedia about "Bernician Series"
The field of biogeochemistry involves scientific study of the chemical, physical, geological, and biological processes and reactions that govern the composition of the natural environment (including the biosphere, the hydrosphere, the pedosphere, the atmosphere, and the lithosphere), and the cycles of matter and energy that transport the Earth's chemical components in time and space. Biogeochemistry is a systems science. ...more on Wikipedia about "Biogeochemistry"
Black sand is a heavy, weakly magnetic, glossy, semi-metallic mixture of usually fine sands, found as part of a placer deposit. ...more on Wikipedia about "Black sand"
Blueschist is a rock that forms by the metamorphism of sodium-rich basic rocks at high pressures and low temperatures, approximately corresponding to a depth of 15 to 30 kilometers and 200 to ~500 degrees Celsius. ...more on Wikipedia about "Blueschist"
(Boring (mechanical))
Auger Drilling
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Boulder clay in geology, is a deposit of clay, often full of boulders, which is formed in and beneath glaciers and ice-sheets wherever they are found, but is in a special sense the typical deposit of the Glacial Period in northern Europe and America. Boulder clay is variously known as till or ground moraine (Ger. Blocklehme, Geschiebsmergel or Grundmorane; Fr. argile a blocc1ux, moraine profonde; Swed. Krosstenslera). It is usually a stiff, tough clay devoid of stratification; though some varieties are distinctly laminated. Occasionally, within the boulder clay, there are irregular lenticular masses of more or less stratified sand, gravel or loam. As the boulder clay is the result of the abrasion (direct or indirect) of the older rocks over which the ice has travelled, it takes its color from them; thus, in Britain, over Triassic and Old Red Sandstone areas the clay is red, over Carboniferous rocks it is often black, over Silurian rock it may be buff or grey, and where the ice has passed over chalk the clay may be quite white and chalky (chalky boulder clay). Much boulder clay is of a bluish-grey color where unexposed, but it becomes brown upon being weathered. ...more on Wikipedia about "Boulder clay"
Bracklesham Beds, in geology, are a series of clays and marls, with sandy and lignitic beds, in the Middle Eocene of the Hampshire Basin, England. ...more on Wikipedia about "Bracklesham Beds"
"A cactolith is a quasihorizontal chonolith composed of anastomosing ductoliths whose distal ends curl like a harpolith, thin like a sphenolith, or bulge discordantly like an akmolith or ethmolith." ...more on Wikipedia about "Cactolith"
Cantabria is a large island that existed in the area of Europe in the Mesozoic era. In later continental drift and orogeny it became most of Spain and Portugal. ...more on Wikipedia about "Cantabria (Mesozoic island)" Pure http://www.shortopedia.com. Pure Information Power. shortopedia
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