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Geologic
Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology. It is integrated with Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface and the processes that have shaped that structure. Geologists study the mineralogical composition of rocks in order to get insight into their history of formation. Geology determines the relative ages of rocks found at a given location; geochemistry (a branch of geology) determines their absolute ages. By combining various petrological, crystallographic, and paleontological tools, geologists are able to chronicle the geological history of the Earth as a whole. One aspect is to demonstrate the age of the Earth. Geology provides evidence for plate tectonics, the evolutionar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of The Earth
The natural history of Earth concerns the development of planet Earth from its formation to the present day. Nearly all branches of natural science have contributed to understanding of the main events of Earth's past, characterized by constant geological change and biological evolution. The geological time scale (GTS), as defined by international convention, depicts the large spans of time from the beginning of Earth to the present, and its divisions chronicle some definitive events of Earth history. Earth formed around 4.54 billion years ago, approximately one-third the age of the universe, by accretion from the solar nebula. Volcanic outgassing probably created the primordial atmosphere and then the ocean, but the early atmosphere contained almost no oxygen. Much of Earth was molten because of frequent collisions with other bodies which led to extreme volcanism. While Earth was in its earliest stage ( Early Earth), a giant impact collision with a planet-sized body named ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologist
A geologist is a scientist who studies the structure, composition, and History of Earth, history of Earth. Geologists incorporate techniques from physics, chemistry, biology, mathematics, and geography to perform research in the Field research, field and the laboratory. Geologists work in the Energy industry, energy and mining sectors to exploit Natural resource, natural resources. They monitor environmental hazards such as earthquakes, volcanoes, tsunamis and landslides. Geologists are also important contributors to climate change discussions. History James Hutton is often viewed as the first modern geologist. In 1785 he presented a paper entitled ''Theory of the Earth'' to the Royal Society of Edinburgh. In his paper, he explained his theory that the Earth must be much older than had previously been supposed to allow enough time for mountains to be eroded and for sediments to form new rocks at the bottom of the sea, which in turn were raised up to become dry land. Hutton pub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologists
A geologist is a scientist who studies the structure, composition, and history of Earth. Geologists incorporate techniques from physics, chemistry, biology, mathematics, and geography to perform research in the field and the laboratory. Geologists work in the energy and mining sectors to exploit natural resources. They monitor environmental hazards such as earthquakes, volcanoes, tsunamis and landslides. Geologists are also important contributors to climate change discussions. History James Hutton is often viewed as the first modern geologist. In 1785 he presented a paper entitled ''Theory of the Earth'' to the Royal Society of Edinburgh. In his paper, he explained his theory that the Earth must be much older than had previously been supposed to allow enough time for mountains to be eroded and for sediments to form new rocks at the bottom of the sea, which in turn were raised up to become dry land. Hutton published a two-volume version of his ideas in 1795Vol. 1 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plate Tectonics
Plate tectonics (, ) 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 , an idea developed during the first decades of the 20th century. Plate tectonics came to be accepted by Earth science, 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 (geology), 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 (geology), fault): , , or . The relative movement of the plates typically ranges from zero to 10 cm annu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Age Of The Earth
The age of Earth is estimated to be 4.54 ± 0.05 billion years. This age may represent the age of Earth's accretion (astrophysics), accretion, or Internal structure of Earth, core formation, or of the material from which Earth formed. This dating is based on evidence from Radiometric dating, radiometric age-dating of meteorite material and is consistent with the radiometric ages of the oldest-known terrestrial material and Moon rock, lunar samples. Following the development of radiometric age-dating in the early 20th century, uranium–lead dating, measurements of lead in uranium-rich minerals showed that some were in excess of a billion years old.For the abstract, see: The oldest such minerals analyzed to date—small crystals of zircon from the Jack Hills of Western Australia—are at least 4.404 billion years old. Calcium–aluminium-rich inclusions—the oldest known solid constituents within meteorites that are formed within the Solar System—are 4.567 billion years old, gi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planetary Science
Planetary science (or more rarely, planetology) is the scientific study of planets (including Earth), celestial bodies (such as moons, asteroids, comets) and planetary systems (in particular those of the Solar System) and the processes of their formation. It studies objects ranging in size from micrometeoroids to gas giants, with the aim of determining their composition, dynamics, formation, interrelations and history. It is a strongly interdisciplinary field, which originally grew from astronomy and Earth science, and now incorporates many disciplines, including planetary geology, cosmochemistry, atmospheric science, physics, oceanography, hydrology, theoretical planetary science, glaciology, and exoplanetology. Allied disciplines include space physics, when concerned with the effects of the Sun on the bodies of the Solar System, and astrobiology. There are interrelated observational and theoretical branches of planetary science. Observational research ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relative Ages
Relative dating is the science of determining the relative order of past events (i.e., the age of an object in comparison to another), without necessarily determining their absolute age (i.e., estimated age). In geology, rock or superficial deposits, fossils and lithologies can be used to correlate one stratigraphic column with another. Prior to the discovery of radiometric dating in the early 20th century, which provided a means of absolute dating, archaeologists and geologists used relative dating to determine ages of materials. Though relative dating can only determine the ''sequential order'' in which a series of events occurred, not ''when'' they occurred, it remains a useful technique. Relative dating by biostratigraphy is the preferred method in paleontology and is, in some respects, more accurate. The Law of Superposition, which states that older layers will be deeper in a site than more recent layers, was the summary outcome of 'relative dating' as observed in geolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geochronology
Geochronology is the science of Chronological dating, determining the age of rock (geology), rocks, fossils, and sediments using signatures inherent in the rocks themselves. Absolute geochronology can be accomplished through radioactive isotopes, whereas relative geochronology is provided by tools such as paleomagnetism and stable isotope ratios. By combining multiple geochronological (and biostratigraphic) indicators the precision of the recovered age can be improved. Geochronology is different in application from biostratigraphy, which is the science of assigning sedimentary rocks to a known geological period via describing, cataloging and comparing fossil floral and faunal assemblages. Biostratigraphy does not ''directly'' provide an absolute age determination of a rock, but merely places it within an ''interval'' of time at which that fossil assemblage is known to have coexisted. Both disciplines work together hand in hand, however, to the point where they share the same syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth Science
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. Geology Geology is broadly the study of Earth's structure, substance, and processes. Geology is largely the study of the lithosphere, or Earth's surface, including the crust and rocks. It includes the physical characteristics and processes that occur in the lithosphere as well as how they are affected by geothermal energy. It incorporates aspects of chemistry, physics, and biology as elements of geology interact. Historical geology is the application of geology to interpret Earth history and how it has changed over time. Geochemistry studies the che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mining
Mining is the Resource extraction, extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agriculture, agricultural processes, or feasibly created Chemical synthesis, artificially in a laboratory or factory. Ores recovered by mining include Metal#Extraction, metals, coal, oil shale, gemstones, limestone, chalk mining, chalk, dimension stone, rock salt, potash, gravel, and clay. The ore must be a rock or mineral that contains valuable constituent, can be extracted or mined and sold for profit. Mining in a wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or even fossil water, water. Modern mining processes involve prospecting for ore bodies, analysis of the profit potential of a proposed mine, extraction of the desired materials, and final mine reclamation, reclamation or restoration of the land after the mine is closed. Mining ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Past Climates
Paleoclimatology ( British spelling, palaeoclimatology) is the scientific study of climates predating the invention of meteorological instruments, when no direct measurement data were available. As instrumental records only span a tiny part of Earth's history, the reconstruction of ancient climate is important to understand natural variation and the evolution of the current climate. Paleoclimatology uses a variety of proxy methods from Earth and life sciences to obtain data previously preserved within rocks, sediments, boreholes, ice sheets, tree rings, corals, shells, and microfossils. Combined with techniques to date the proxies, the paleoclimate records are used to determine the past states of Earth's atmosphere. The scientific field of paleoclimatology came to maturity in the 20th century. Notable periods studied by paleoclimatologists include the frequent glaciations that Earth has undergone, rapid cooling events like the Younger Dryas, and the rapid warming du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
