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57-546: N165 ( "Coronation" rock ) is a rock on the surface of Aeolis Palus in Gale Crater on the planet Mars near the landing site ("Bradbury Landing") of the Curiosity rover . The "approximate" site coordinates are: 4°35′S 137°26′E  /  4.59°S 137.44°E  / -4.59; 137.44 . On August 19, 2012, the rock was the first target of the rover's laser instrument, ChemCam , which can analyze targets at

114-420: A laboratory or factory . Mining in a wider sense comprises extraction of any resource (e.g. petroleum , natural gas , salt or even water ) from the earth. Mining of rock and metals has been done since prehistoric times. Modern mining processes involve prospecting for mineral deposits, analysis of the profit potential of a proposed mine, extraction of the desired materials, and finally reclamation of

171-500: A concise, clear manner, “keeping Hutton's approach alive” following his death in 1797, as other scientists interpreted his theory in their own manner. Additionally, John Playfair would argue Plutonism being the correct theory as opposed to Neptunism. In 1830, a scientist named Charles Lyell, founded uniformitarianism . In 1830, Lyell published the Principles of Geology , in which the Earth

228-453: A core aspect, similar to how uniformitarianism implemented plutonism as a core aspect. His theory suggested that the Earth’s landscape has come to be through volatile forces that the Earth system possess that come in and out of existence. This theory was favoured by the scientific community at the time, and hence, neptunism by default was still maintaining its dominance over plutonism. However,

285-440: A distance using a laser and spectrometer. A Twitter feed for the rock was created, featuring an anthropomorphized account of its experiences. Its posts include a humor themed mix of social interaction and Mars content such as " Did you know I was born in a volcano? Basalts like me come from lava. That's why we call it Olympus Mom ". The goal of this initial use of the laser on Mars was to serve as target practice for characterizing

342-402: A fourth class of rocks alongside igneous, sedimentary, and metamorphic. Rock varies greatly in strength, from quartzites having a tensile strength in excess of 300 MPa to sedimentary rock so soft it can be crumbled with bare fingers (that is, it is friable ). (For comparison, structural steel has a tensile strength of around 350 MPa. ) Relatively soft, easily worked sedimentary rock

399-433: A huge impact on the cultural and technological development of the human race. Rock has been used by humans and other hominids for at least 2.5 million years . Lithic technology marks some of the oldest and continuously used technologies. The mining of rock for its metal content has been one of the most important factors of human advancement, and has progressed at different rates in different places, in part because of

456-415: A more concise and clear manner that allowed the presence of plutonism to remain in the opposition of neptunism in the scientific community. Werner’s theory was developed through his observations of a selected group of rocks, as his position at the university prevented him from make observations and developing his theory on a wider array of rocks. Hence, when other rocks were observed from different parts of

513-562: A source area and then transported to the place of deposition by water , wind , ice , mass movement or glaciers (agents of denudation ). About 7.9% of the crust by volume is composed of sedimentary rocks, with 82% of those being shales, while the remainder consists of 6% limestone and 12% sandstone and arkoses . Sedimentary rocks often contain fossils . Sedimentary rocks form under the influence of gravity and typically are deposited in horizontal or near horizontal layers or strata , and may be referred to as stratified rocks. Sediment and

570-413: A sufficient temperature, resulting in the formation of “a more silicic andesite” composition, which is less dense than the original basaltic magma. This allows magma to proceed through the crust, resulting in the occurrence of explosive volcanoes. Volcanic rocks form from the lava cooling on the Earth's surface. However, in the event when the occurrence of subduction or temperature within the magma chamber

627-713: A texture are referred to as foliated ; the remainders are termed non-foliated. The name of the rock is then determined based on the types of minerals present. Schists are foliated rocks that are primarily composed of lamellar minerals such as micas . A gneiss has visible bands of differing lightness , with a common example being the granite gneiss. Other varieties of foliated rock include slates , phyllites , and mylonite . Familiar examples of non-foliated metamorphic rocks include marble , soapstone , and serpentine . This branch contains quartzite —a metamorphosed form of sandstone —and hornfels . Though most understanding of rocks comes from those of Earth, rocks make up many of

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684-459: Is an equilibrium state, where biological, chemical and physical processes have occurred slowly over an extreme amount of time, resulting in the observed features on the Earth's surface. The theory included aspects of plutonism as core concepts resulting in the de facto general acceptance of plutonism, as uniformitarianism became widely accepted within the scientific community, resulting in Hutton becoming

741-556: Is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition , and the way in which it is formed. Rocks form the Earth's outer solid layer, the crust , and most of its interior, except for the liquid outer core and pockets of magma in the asthenosphere . The study of rocks involves multiple subdisciplines of geology, including petrology and mineralogy . It may be limited to rocks found on Earth, or it may include planetary geology that studies

798-458: Is formed through the cooling and solidification of magma or lava . This magma may be derived from partial melts of pre-existing rocks in either a planet 's mantle or crust . Typically, the melting of rocks is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Igneous rocks are divided into two main categories: Magmas tend to become richer in silica as they rise towards

855-427: Is insufficient, the magma chamber within the volcano would crystallise, resulting in the extinction of the volcano and the formation of intrusive igneous rock, also referred to as plutonic rocks or “plutons”. In some instances, a separate chamber may crystallise, hence not resulting in the extinction of the volcano. In the event of uplift/erosion mountain building occurs, batholith rocks occur. Additionally, some of

912-442: Is next in importance. About 65% of the Earth's crust by volume consists of igneous rocks. Of these, 66% are basalt and gabbro , 16% are granite, and 17% granodiorite and diorite . Only 0.6% are syenite and 0.3% are ultramafic . The oceanic crust is 99% basalt, which is an igneous rock of mafic composition. Granite and similar rocks, known as granitoids , dominate the continental crust . Sedimentary rocks are formed at

969-453: Is the study of Earth and its components, including the study of rock formations. Petrology is the study of the character and origin of rocks. Mineralogy is the study of the mineral components that create rocks. The study of rocks and their components has contributed to the geological understanding of Earth's history, the archaeological understanding of human history, and the development of engineering and technology in human society. While

1026-417: The history of geology includes many theories of rocks and their origins that have persisted throughout human history, the study of rocks was developed as a formal science during the 19th century. Plutonism was developed as a theory during this time, and the discovery of radioactive decay in 1896 allowed for the radiocarbon dating of rocks. Understanding of plate tectonics developed in the second half of

1083-404: The subduction zone , though this magma fails to reach past the base of the continental crust due to its higher density. However, when heat is applied to the crust, an area of granitic magma can be produced through the melting of the continental crust when contributing to metamorphism. Partial crystallization and magma mixing, among other igneous processes occur once the basaltic magma cools to

1140-426: The 18th century scientists enquired about the process and context in which the current rock landscape on the Earth's surface came into existence and why it was in the current arrangement. From this enquiry came about two prevailing theories: plutonism, which was proposed by James Hutton , and neptunism , which was proposed by Abraham Gottlob Werner . It has been noted within the scientific community that they were not

1197-399: The 20th century. Rocks are composed primarily of grains of minerals, which are crystalline solids formed from atoms chemically bonded into an orderly structure. Some rocks also contain mineraloids , which are rigid, mineral-like substances, such as volcanic glass , that lack crystalline structure. The types and abundance of minerals in a rock are determined by the manner in which it

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1254-467: The Earth's surface, a process called magma differentiation . This occurs both because minerals low in silica crystallize out of the magma as it begins to cool ( Bowen's reaction series ) and because the magma assimilates some of the crustal rock through which it ascends ( country rock ), and crustal rock tends to be high in silica. Silica content is thus the most important chemical criterion for classifying igneous rock. The content of alkali metal oxides

1311-503: The Earth's surface: temperatures greater than 150 to 200 °C and pressures greater than 1500 bars. This occurs, for example, when continental plates collide. Metamorphic rocks compose 27.4% of the crust by volume. The three major classes of metamorphic rock are based upon the formation mechanism. An intrusion of magma that heats the surrounding rock causes contact metamorphism—a temperature-dominated transformation. Pressure metamorphism occurs when sediments are buried deep under

1368-481: The cause of the current landscape, with no modern equivalency. Hutton proposed the Earth was undergoing a slow but continuous changes, where such changes on the Earth namely occur through volcanism , erosion , transportation and deposition of sediments. He used the Glen Tilt of Perthshire as evidence to support his argument, where the used location was used as an example of the neptunist theory prior to his hypothesis of

1425-523: The constituent particles, and particle size . These physical properties are the result of the processes that formed the rocks. Over the course of time, rocks can be transformed from one type into another, as described by a geological model called the rock cycle . This transformation produces three general classes of rock: igneous , sedimentary and metamorphic . Those three classes are subdivided into many groups. There are, however, no hard-and-fast boundaries between allied rocks. By increase or decrease in

1482-495: The development of metallurgy . Plutonism The Oxford English Dictionary traces use of the word "plutonists" to 1799, and the appearance of the word plutonism to 1842. Abbé Anton Moro , who had studied volcanic islands, first proposed the theory before 1750, and James Hutton subsequently developed it as part of his Theory of the Earth , published in 1788, which used rock formations at Glen Tilt in Perthshire as

1539-491: The earliest humans. This early period, called the Stone Age , saw the development of many stone tools. Stone was then used as a major component in the construction of buildings and early infrastructure . Mining developed to extract rocks from the Earth and obtain the minerals within them, including metals . Modern technology has allowed the development of new human-made rocks and rock-like substances, such as concrete . Geology

1596-566: The early 19th century, and eventually the plutonist views on the origin of rocks prevailed in the wake of the work of Charles Lyell in the 1830s, who incorporated this theory into uniformitarianism . However, geologists regard sedimentary rocks such as limestone as having resulted from processes like those described by the neptunists. Comparatively, plutonism within uniformitarianism is equivalent to neptunism within catastrophism, as both are used as core concepts within their respective theories, and hence similarly, neptunism opposes plutonism in

1653-606: The earth's surface by the accumulation and cementation of fragments of earlier rocks, minerals, and organisms or as chemical precipitates and organic growths in water ( sedimentation ). This process causes clastic sediments (pieces of rock) or organic particles ( detritus ) to settle and accumulate or for minerals to chemically precipitate ( evaporite ) from a solution . The particulate matter then undergoes compaction and cementation at moderate temperatures and pressures ( diagenesis ). Before being deposited, sediments are formed by weathering of earlier rocks by erosion in

1710-427: The earth, from an ore body, vein or seam . The term also includes the removal of soil. Materials recovered by mining include base metals , precious metals , iron , uranium , coal , diamonds , limestone , oil shale , rock salt , potash , construction aggregate and dimension stone . Mining is required to obtain any material that cannot be grown through agricultural processes, or created artificially in

1767-541: The first ones to propose such theories, but they were the ones credited with proposing their corresponding theories to the scientific community. One of the first notable scientists to propose an early theory of plutonism was Abbé Anton Moro , who in the first half of the 18th century was able to inform the scientific community how to differentiate between volcanic and sedimentary rocks. Through observing crustaceans , it led him to discover that within mountains lied petrified fossils. This suggested to him that at one point in

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1824-486: The granite present there. He published his theory and findings in an essay in 1788, which was followed by his two-volume work tilted Theory of the Earth in 1795, which expanded upon his 1788 work. In 1802, Illustrations of the Huttonian Theory was published by John Playfair, which attempted to siphon the influence of Neptunism at the time. The Illustrations portrayed Hutton's “length and obscurely written book” in

1881-402: The ground; pressure is dominant, and temperature plays a smaller role. This is termed burial metamorphism, and it can result in rocks such as jade . Where both heat and pressure play a role, the mechanism is termed regional metamorphism. This is typically found in mountain-building regions. Depending on the structure, metamorphic rocks are divided into two general categories. Those that possess

1938-481: The instrument. The rock was primarily selected for its proximity to the rover, rather than any intrinsic scientific value. The rock was lasered thirty times over ten seconds. The mission's investigators thought the rock was a basalt prior to lasing, which was confirmed by preliminary results. The ChemCam team reported positive results; they worked on the instrument for eight years before getting to use it on Mars. Rock (geology) In geology , rock (or stone )

1995-402: The islands and continents, as he argued it was a slow process, whilst others argued it was catastrophic and had no modern equivalences. Neptunists believed that the Earth's surface initially only contained a turbid ocean, which led to deposits of sediments on the ocean resulting in the formation of crystalline rocks such as granites. There were many opposing views between the two theories, one of

2052-491: The kind of metals available from the rock of a region. Anthropic rock is synthetic or restructured rock formed by human activity. Concrete is recognized as a human-made rock constituted of natural and processed rock and having been developed since Ancient Rome . Rock can also be modified with other substances to develop new forms, such as epoxy granite . Artificial stone has also been developed, such as Coade stone . Geologist James R. Underwood has proposed anthropic rock as

2109-431: The land to prepare it for other uses once mining ceases. Mining processes may create negative impacts on the environment both during the mining operations and for years after mining has ceased. These potential impacts have led to most of the world's nations adopting regulations to manage negative effects of mining operations. Stone tools have been used for millions of years by humans and earlier hominids . The Stone Age

2166-486: The magma within the Earth is produced without subduction, resulting in the formation of “sticky granite magma”, and is without a conduit to reach the surface. Instead, it forces its way through rock crevices, resulting in a high-pressure environment. Cooling then occurs, over a long period of time, resulting in large coarse-grained crystals which form bodies with distinctive textures, resulting in intrusive igneous/plutonic rocks. These rocks vary in size and colour. During

2223-417: The more notable oppositions of each theory was the formation of granite . Hutton believed that the granites were injected within the Glen Tilt of Perthshire as they were intruded through Dalradian metasediments , indicated by the cut across sediment layers. This indicated to Hutton that the sediments were older than the granite. This contradicted Neptunism, as it believes granites to be precipitated out of

2280-489: The neptunist view that rocks had formed by processes that no longer operated, instead supporting Hutton's theory . A key issue of the debate revolved around the neptunist belief that basalt was sedimentary, and some fossils had been found in it. Against this, Hutton's supporter John Playfair (1748–1819) argued that this rock contained no fossils as it had formed from molten magma, and it had been found cutting through other rocks in volcanic dykes . The arguments continued into

2337-579: The ocean, hence being the oldest rock type. In 1773, prior to Hutton’s observations, Abraham Gottlob Werner published his mineralogy book On the External Characteristics of Fossils , which categorised minerals through their physical characteristics alone, which allowed him to obtain the position of Curator of Freiburg School of Mining’s mineral collection and teacher of mining, where he was able to promote his theory of neptunism. Through his prestigious position, he attracted many students where he

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2394-418: The original rock was formed. This process is called metamorphism , meaning to "change in form". The result is a profound change in physical properties and chemistry of the stone. The original rock, known as the protolith , transforms into other mineral types or other forms of the same minerals, by recrystallization . The temperatures and pressures required for this process are always higher than those found at

2451-425: The particles of clastic sedimentary rocks can be further classified by grain size . The smallest sediments are clay , followed by silt , sand , and gravel . Some systems include cobbles and boulders as measurements. Metamorphic rocks are formed by subjecting any rock type—sedimentary rock, igneous rock or another older metamorphic rock—to different temperature and pressure conditions than those in which

2508-451: The past, through the force of volcanic fire, islands and continents rose from the bottom of the sea. He argued that this occurred over a long period of time as opposed to a relatively short amount of time, indicating some sort of continuous change that has and is occurring on the Earth’s surface, leading to the current formations viewed by humanity. In the 1780s, Hutton started opposing the neptunist view of previous catastrophic events being

2565-455: The prime example supporting his theory; an example used by Neptunism to prove their theory as well. The idea contested Abraham Werner's neptunist theory which proposed that the Earth had formed from a mass of water and suspended material which had formed rocks as layers of deposited sediment which became the continents when the water retreated, further layers being deposited by floods and some volcanic activity. Plutonists strongly disputed

2622-420: The production of magma. The process of magma production occurs during the process of mountain formation in which two specific locations where magma would be generated. The first involves high-grade metamorphism occurring within “thickened continental crust ” resulting in granitic magma, hence resulting in a direct formation. The second method involves basaltic magma forming over a larger area, located above

2679-462: The proportions of their minerals, they pass through gradations from one to the other; the distinctive structures of one kind of rock may thus be traced, gradually merging into those of another. Hence the definitions adopted in rock names simply correspond to selected points in a continuously graduated series. Igneous rock (derived from the Latin word igneus, meaning of fire, from ignis meaning fire)

2736-641: The rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks , sedimentary rocks and metamorphic rocks . Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments , which in turn are formed by the weathering , transport, and deposition of existing rocks. Metamorphic rocks are formed when existing rocks are subjected to such high pressures and temperatures that they are transformed without significant melting. Humanity has made use of rocks since

2793-415: The same way that catastrophism opposes uniformitarianism. Plutonism is a geological theory proposed by James Hutton, where he proposed that the main cause of the current arrangement of rocks and the Earth's surface landscape was driven through the heat provided by magma concealed within surface of the Earth, which occurred over the course of thousands if not millions of years. This process is influenced by

2850-610: The universe's celestial bodies. In the Solar System , Mars , Venus , and Mercury are composed of rock, as are many natural satellites , asteroids , and meteoroids . Meteorites that fall to Earth provide evidence of extraterrestrial rocks and their composition. They are typically heavier than rocks on Earth. Asteroid rocks can also be brought to Earth through space missions, such as the Hayabusa mission. Lunar rocks and Martian rocks have also been studied. The use of rock has had

2907-594: The world, conformity to neptunism decreased with each type of rock being examined. This development was noticeable in the work of Alexander von Humboldt (1769–1859), who had studied with Werner in Freiberg and gradually departed from his teacher's theories. Due to this trend, neptunism declined after Werner’s death in 1817, leaving the battle of neptunism and plutonism in a relative stagnation as pro-plutonism and pro-neptunism scientists attempted to ensure their respective theory became accepted. Despite this stalemate, neptunism

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2964-405: The “Father of Geology”, due to the presence of Hutton's work as core concepts. As mentioned prior, there were two prevailing theories during the 18th century to explain the current arrangement of the landscape and rock formations: plutonism and neptunism. The schism was pseudo-initiated through Moro’s differentiation of sedimentary and volcanic rocks, as well as his theory of volcanic fire lifting

3021-408: Was a period of widespread stone tool usage. Early Stone Age tools were simple implements, such as hammerstones and sharp flakes. Middle Stone Age tools featured sharpened points to be used as projectile points , awls, or scrapers . Late Stone Age tools were developed with craftsmanship and distinct cultural identities. Stone tools were largely superseded by copper and bronze tools following

3078-450: Was able to spread neptunism to general scientific community as they entered the field geology and any other connecting fields. As Hutton died in 1797, plutonism was less vocal within the scientific community at the time as it received scepticism from pro-neptunism individuals. As mentioned above, John Playfair published his Illustrations of Huttonian Theory , which siphoned the influence of neptunism, as Playfair depicted Hutton’s theory in

3135-456: Was formed. Most rocks contain silicate minerals , compounds that include silica tetrahedra in their crystal lattice , and account for about one-third of all known mineral species and about 95% of the earth's crust . The proportion of silica in rocks and minerals is a major factor in determining their names and properties. Rocks are classified according to characteristics such as mineral and chemical composition, permeability , texture of

3192-477: Was partially favoured to plutonism due to Werner’s position allowing him to spread his theory due to a larger degree of individuals within the university and scientific community being influenced by him. Hence, many of his students favoured neptunism over plutonism. Sometime in the early 19th century, prior to Lyell’s contributions, a French scientist named Georges Cuvier utilised Werner’s neptunism theory within his theory of catastrophism , which had neptunism as

3249-760: Was quarried for construction as early as 4000 BCE in Egypt, and stone was used to build fortifications in Inner Mongolia as early as 2800 BCE. The soft rock, tuff , is common in Italy, and the Romans used it for many buildings and bridges. Limestone was widely used in construction in the Middle Ages in Europe and remained popular into the 20th century. Mining is the extraction of valuable minerals or other geological materials from

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