Archaeology
Archaeology, or archeology, is the study of human activity through the recovery and analysis of material culture. The archaeological record consists of artifacts, biofacts or ecofacts, Archaeology can be considered both a social science and a branch of the humanities. In North America, archaeology is considered a sub-field of anthropology, archaeologists study human prehistory and history, from the development of the first stone tools at Lomekwi in East Africa 3.3 million years ago up until recent decades. Archaeology as a field is distinct from the discipline of palaeontology, Archaeology is particularly important for learning about prehistoric societies, for whom there may be no written records to study. Prehistory includes over 99% of the human past, from the Paleolithic until the advent of literacy in societies across the world, Archaeology has various goals, which range from understanding culture history to reconstructing past lifeways to documenting and explaining changes in human societies through time.
The discipline involves surveying and eventually analysis of data collected to learn more about the past, in broad scope, archaeology relies on cross-disciplinary research. Archaeology developed out of antiquarianism in Europe during the 19th century, Archaeology has been used by nation-states to create particular visions of the past. Nonetheless, archaeologists face many problems, such as dealing with pseudoarchaeology, the looting of artifacts, a lack of public interest, the science of archaeology grew out of the older multi-disciplinary study known as antiquarianism. Antiquarians studied history with attention to ancient artifacts and manuscripts. Tentative steps towards the systematization of archaeology as a science took place during the Enlightenment era in Europe in the 17th and 18th centuries, in Europe, philosophical interest in the remains of Greco-Roman civilization and the rediscovery of classical culture began in the late Middle Age. Antiquarians, including John Leland and William Camden, conducted surveys of the English countryside, one of the first sites to undergo archaeological excavation was Stonehenge and other megalithic monuments in England.
John Aubrey was a pioneer archaeologist who recorded numerous megalithic and other monuments in southern England. He was ahead of his time in the analysis of his findings and he attempted to chart the chronological stylistic evolution of handwriting, medieval architecture and shield-shapes. Excavations were carried out in the ancient towns of Pompeii and Herculaneum and these excavations began in 1748 in Pompeii, while in Herculaneum they began in 1738. The discovery of entire towns, complete with utensils and even human shapes, prior to the development of modern techniques, excavations tended to be haphazard, the importance of concepts such as stratification and context were overlooked. The father of archaeological excavation was William Cunnington and he undertook excavations in Wiltshire from around 1798, funded by Sir Richard Colt Hoare. Cunnington made meticulous recordings of neolithic and Bronze Age barrows, one of the major achievements of 19th century archaeology was the development of stratigraphy.
The idea of overlapping strata tracing back to successive periods was borrowed from the new geological and paleontological work of scholars like William Smith, James Hutton, the application of stratigraphy to archaeology first took place with the excavations of prehistorical and Bronze Age sites
Utah
Utah is a state in the western United States. It became the 45th state admitted to the U. S. on January 4,1896, Utah is the 13th-largest by area, 31st-most-populous, and 10th-least-densely populated of the 50 United States. Utah has a population of more than 3 million, approximately 80% of whom live along the Wasatch Front, Utah is bordered by Colorado to the east, Wyoming to the northeast, Idaho to the north, Arizona to the south, and Nevada to the west. It touches a corner of New Mexico in the southeast, approximately 62% of Utahns are reported to be members of The Church of Jesus Christ of Latter-day Saints or LDS, which greatly influences Utahn culture and daily life. The LDS Churchs world headquarters is located in Salt Lake City, Utah is the only state with a majority population belonging to a single church. The state is a center of transportation, information technology and research, government services, mining, in 2013, the U. S. Census Bureau estimated that Utah had the second fastest-growing population of any state.
St. George was the metropolitan area in the United States from 2000 to 2005. Utah has the 14th highest median income and the least income inequality of any U. S. state. A2012 Gallup national survey found Utah overall to be the best state to live in based on 13 forward-looking measurements including various economic, the name Utah is derived from the name of the Ute tribe. It means people of the mountains in the Ute language, according to other sources Utah is derived from the Apache name Yudah which means Tall. These Native American tribes are subgroups of the Ute-Aztec Native American ethnicity and were sedentary, the Ancestral Pueblo people built their homes through excavations in mountains, and the Fremont people built houses of straw before disappearing from the region around the 15th century. Another group of Native Americans, the Navajo, settled in the region around the 18th century, in the mid-18th century, other Uto-Aztecan tribes, including the Goshute, the Paiute, the Shoshone, and the Ute people, settled in the region.
These five groups were present when the first European explorers arrived, the southern Utah region was explored by the Spanish in 1540, led by Francisco Vásquez de Coronado, while looking for the legendary Cíbola. A group led by two Catholic priests—sometimes called the Dominguez-Escalante Expedition—left Santa Fe in 1776, hoping to find a route to the coast of California, the expedition traveled as far north as Utah Lake and encountered the native residents. The Spanish made further explorations in the region, but were not interested in colonizing the area because of its desert nature, in 1821, the year Mexico achieved its independence from Spain, the region became known as part of its territory of Alta California. European trappers and fur traders explored some areas of Utah in the early 19th century from Canada, the city of Provo, Utah was named for one, Étienne Provost, who visited the area in 1825. The city of Ogden, Utah was named after Peter Skene Ogden, in late 1824, Jim Bridger became the first known English-speaking person to sight the Great Salt Lake.
Due to the salinity of its waters, Bridger thought he had found the Pacific Ocean
Nicolas Steno
Nicolas Steno was a Danish scientist, a pioneer in both anatomy and geology who became a Catholic bishop in his years. Steno was trained in the texts on science, however. Importantly he questioned explanations for tear production, the idea that grew in the ground. His investigations and his subsequent conclusions on fossils and rock formation have led scholars to consider him one of the founders of modern stratigraphy, born to a Lutheran family, Steno converted to Catholicism in 1667. After his conversion, his interest for natural sciences rapidly waned giving way to his interest in theology, at the beginning of 1675, he decided to become a priest. Four months after, he was ordained in the Catholic clergy in Easter 1675, as a clergyman, he was appointed Vicar Apostolic of Nordic Missions and Titular Bishop of Titopolis by Pope Innocent XI. Steno played a role in the Counter-Reformation in Northern Germany. He was venerated as a saint after his death and the Roman Catholic canonization process was begun in 1938, Pope John Paul II beatified Steno in 1988.
Nicolas Steno was born in Copenhagen on New Years Day 1638 and he became ill at age three, suffering from an unknown disease, and grew up in isolation during his childhood. In 1644 his father died, after which his mother married another goldsmith, in 1654–1655,240 pupils of his school died due to the plague. Across the street lived Peder Schumacher, at the age of 19, Steno entered the University of Copenhagen to pursue medical studies. After completing his university education, Steno set out to travel through Europe, in fact, in the Netherlands, France and Germany he came into contact with prominent physicians and scientists. These influences led him to use his own powers of observation to make important scientific discoveries, at the urging of Thomas Bartholin, Steno first travelled to Rostock, to Amsterdam, where he studied anatomy under and lodged with Gerard Blasius, focusing on the lymphatic system. Within a few months Steno moved to Leiden, where he met the students Jan Swammerdam, Frederik Ruysch, Reinier de Graaf, Franciscus de le Boe Sylvius, a famous professor, and Baruch Spinoza.
At the time Descartes was publishing on the working of the brain, invited to Paris by Henri Louis Habert de Montmor and Pierre Bourdelot, he there met Ole Borch and Melchisédech Thévenot who were interested in new research and in demonstrations of his skills. In 1665 Steno travelled to Saumur and Montpellier, where he met Martin Lister and William Croone, Steno was invited to live in the Palazzo Vecchio, in return he had to gather a cabinet of curiosities. Steno went to Rome and met Pope Alexander VII and Marcello Malpighi, on his way back he watched a Corpus Christi procession in Livorno and wondered if he had the right belief. In Florence Steno focused on the system and the nature of muscle contraction
Colorado Plateau
The province covers an area of 337,000 km2 within western Colorado, northwestern New Mexico and eastern Utah, and northern Arizona. About 90% of the area is drained by the Colorado River and its tributaries, the Green, San Juan. Most of the remainder of the plateau is drained by the Rio Grande, the Colorado Plateau is largely made up of high desert, with scattered areas of forests. In the southwest corner of the Colorado Plateau lies the Grand Canyon of the Colorado River, much of the Plateaus landscape is related, in both appearance and geologic history, to the Grand Canyon. The nickname Red Rock Country suggests the brightly colored rock left bare to the view by dryness, hoodoos, reefs, river narrows, natural bridges, and slot canyons are only some of the additional features typical of the Plateau. The Colorado Plateau has the greatest concentration of U. S. National Park Service units in the country outside of the Washington, DC metropolitan area. Among its ten National Parks are Grand Canyon, Glen Canyon, Bryce Canyon, Capitol Reef, Arches, Mesa Verde, and Petrified Forest.
The province is bounded by the Rocky Mountains in Colorado, and by the Uinta Mountains and Wasatch Mountains branches of the Rockies in northern and it is bounded by the Rio Grande Rift, Mogollon Rim and the Basin and Range Province. Isolated ranges of the Southern Rocky Mountains such as the San Juan Mountains in Colorado, north-south trending normal faults that include the Hurricane, Grand Wash, and Paunsaugunt separate the sections component plateaus. This fault pattern is caused by the forces pulling apart the adjacent Basin and Range province to the west. Occupying the southeast corner of the Colorado Plateau is the Datil Section, thick sequences of mid-Tertiary to late-Cenozoic-aged lava covers this section. Development of the province has in part been influenced by structural features in its oldest rocks. Part of the Wasatch Line and its various faults form the edge of the province. Faults that run parallel to the Wasatch Fault that lies along the Wasatch Range form the boundaries between the plateaus in the High Plateaus Section, the Uinta Basin, Uncompahgre Uplift, and the Paradox Basin were created by movement along structural weaknesses in the regions oldest rock.
Some sources include the Tushar Mountain Plateau as part of the Colorado Plateau, the mostly flat-lying sedimentary rock units that make up these plateaus are found in component plateaus that are between 1500 m to over 3350 m above sea level. A supersequence of these rocks is exposed in the various cliffs, within these rocks are abundant mineral resources that include uranium, coal and natural gas. Study of the unusually clear geologic history has greatly advanced that science. A rain shadow from the Sierra Nevada far to the west, higher areas receive more precipitation and are covered in forests of pine and spruce
Radiometric dating
Radiometric dating or radioactive dating is a technique used to date materials such as rocks or carbon, in which trace radioactive impurities were selectively incorporated when they were formed. The method compares the abundance of a naturally occurring radioactive isotope within the material to the abundance of its decay products, together with stratigraphic principles, radiometric dating methods are used in geochronology to establish the geological time scale. Among the best-known techniques are radiocarbon dating, potassium-argon dating and uranium-lead dating, by allowing the establishment of geological timescales, it provides a significant source of information about the ages of fossils and the deduced rates of evolutionary change. Radiometric dating is used to date archaeological materials, including ancient artifacts. Different methods of radiometric dating vary in the timescale over which they are accurate, all ordinary matter is made up of combinations of chemical elements, each with its own atomic number, indicating the number of protons in the atomic nucleus.
Additionally, elements may exist in different isotopes, with each isotope of an element differing in the number of neutrons in the nucleus, a particular isotope of a particular element is called a nuclide. That is, at point in time, an atom of such a nuclide will undergo radioactive decay. This transformation may be accomplished in a number of different ways, including alpha decay, another possibility is spontaneous fission into two or more nuclides. After one half-life has elapsed, one half of the atoms of the nuclide in question will have decayed into a daughter nuclide or decay product, Isotopic systems that have been exploited for radiometric dating have half-lives ranging from only about 10 years to over 100 billion years. For most radioactive nuclides, the half-life depends solely on nuclear properties and is essentially a constant and it is not affected by external factors such as temperature, chemical environment, or presence of a magnetic or electric field. The only exceptions are nuclides that decay by the process of capture, such as beryllium-7, strontium-85.
For all other nuclides, the proportion of the nuclide to its decay products changes in a predictable way as the original nuclide decays over time. This predictability allows the relative abundances of related nuclides to be used as a clock to measure the time from the incorporation of the original nuclides into a material to the present. The basic equation of radiometric dating requires that neither the parent nuclide nor the product can enter or leave the material after its formation. The possible confounding effects of contamination of parent and daughter isotopes have to be considered and it is therefore essential to have as much information as possible about the material being dated and to check for possible signs of alteration. Precision is enhanced if measurements are taken on multiple samples from different locations of the rock body and this can reduce the problem of contamination. In uranium-lead dating, the diagram is used which decreases the problem of nuclide loss. Finally, correlation between different isotopic dating methods may be required to confirm the age of a sample, the procedures used to isolate and analyze the parent and daughter nuclides must be precise and accurate
Evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. Evolutionary processes give rise to biodiversity at every level of organisation, including the levels of species, individual organisms. In July 2016, scientists reported identifying a set of 355 genes from the LUCA of all living on Earth. The fossil record includes a progression from early biogenic graphite, to microbial mat fossils, existing patterns of biodiversity have been shaped both by speciation and by extinction. More than 99 percent of all species that lived on Earth are estimated to be extinct. Estimates of Earths current species range from 10 to 14 million, more recently, in May 2016, scientists reported that 1 trillion species are estimated to be on Earth currently with only one-thousandth of one percent described. In the mid-19th century, Charles Darwin formulated the theory of evolution by natural selection. This teleonomy is the quality whereby the process of natural selection creates and preserves traits that are fitted for the functional roles they perform.
The processes by which the changes occur, from one generation to another, are called evolutionary processes or mechanisms, the four most widely recognized evolutionary processes are natural selection, genetic drift and gene migration. Natural selection and genetic drift sort variation and gene migration create variation, consequences of selection can include meiotic drive, nonrandom mating and genetic hitchhiking. In the early 20th century the modern evolutionary synthesis integrated classical genetics with Darwins theory of evolution by natural selection through the discipline of population genetics, the importance of natural selection as a cause of evolution was accepted into other branches of biology. Moreover, previously held notions about evolution, such as orthogenesis, evolutionary computation, a sub-field of artificial intelligence, involves the application of Darwinian principles to problems in computer science. The proposal that one type of organism could descend from another type goes back to some of the first pre-Socratic Greek philosophers, such as Anaximander, such proposals survived into Roman times.
The poet and philosopher Lucretius followed Empedocles in his masterwork De rerum natura, in contrast to these materialistic views, Aristotelianism considered all natural things as actualisations of fixed natural possibilities, known as forms. This was part of a teleological understanding of nature in which all things have an intended role to play in a divine cosmic order. In the 17th century, the new method of modern science rejected the Aristotelian approach, this new approach was slow to take root in the biological sciences, the last bastion of the concept of fixed natural types. The biological classification introduced by Carl Linnaeus in 1735 explicitly recognized the nature of species relationships. Other naturalists of this time speculated on the change of species over time according to natural laws
Speciation
Speciation is the evolutionary process by which biological populations evolve to become distinct species. The biologist Orator F. Cook coined the term speciation in 1906 for the splitting of lineages or cladogenesis, Charles Darwin was the first to describe the role of natural selection in speciation in his 1859 book The Origin of Species. He identified sexual selection as a mechanism, but found it problematic. There are four modes of speciation in nature, based on the extent to which speciating populations are isolated from one another, peripatric, parapatric. Speciation may be induced artificially, through animal husbandry, whether genetic drift is a minor or major contributor to speciation is the subject matter of much ongoing discussion. All forms of speciation have taken place over the course of evolution, however. During allopatric speciation, a population splits into two isolated populations. When the populations come back into contact, they have evolved such that they are isolated and are no longer capable of exchanging genes.
Island genetics is the associated with the tendency of small. Examples include insular dwarfism and the changes among certain famous island chains. The Galápagos Islands are particularly famous for their influence on Charles Darwin, though the finches were less important for Darwin, more recent research has shown the birds now known as Darwins finches to be a classic case of adaptive evolutionary radiation. In peripatric speciation, a subform of allopatric speciation, new species are formed in isolated and it is related to the concept of a founder effect, since small populations often undergo bottlenecks. Genetic drift is often proposed to play a significant role in peripatric speciation, parapatric speciation may be associated with differential landscape-dependent selection. Even if there is a gene flow between two populations, strong differential selection may impede assimilation and different species may eventually develop, habitat differences may be more important in the development of reproductive isolation than the isolation time.
Ecologists refer to parapatric and peripatric speciation in terms of ecological niches, a niche must be available in order for a new species to be successful. Ring species such as Larus gulls have been claimed to illustrate speciation in progress, the grass Anthoxanthum odoratum may be starting parapatric speciation in areas of mine contamination. Sympatric speciation refers to the formation of two or more descendant species from an ancestral species all occupying the same geographic location. Often-cited examples of sympatric speciation are found in insects that become dependent on different host plants in the same area, the existence of sympatric speciation as a mechanism of speciation remains highly debated
Cyprus
Cyprus, officially the Republic of Cyprus, is an island country in the Eastern Mediterranean and the third largest and third most populous island in the Mediterranean. It is located south of Turkey, west of Syria and Lebanon, northwest of Israel and Palestine, north of Egypt, the earliest known human activity on the island dates to around the 10th millennium BC. Archaeological remains from this include the well-preserved Neolithic village of Khirokitia. Cyprus was settled by Mycenaean Greeks in two waves in the 2nd millennium BC, Cyprus was placed under British administration based on Cyprus Convention in 1878 and formally annexed by Britain in 1914. While Turkish Cypriots made up 18% of the population, the partition of Cyprus and creation of a Turkish state in the north became a policy of Turkish Cypriot leaders, following nationalist violence in the 1950s, Cyprus was granted independence in 1960. On 15 July 1974, a coup détat was staged by Greek Cypriot nationalists and elements of the Greek military junta in an attempt at enosis and these events and the resulting political situation are matters of a continuing dispute.
The Cyprus Republic has de jure sovereignty over the island of Cyprus, as well as its territorial sea and exclusive economic area, another nearly 4% of the islands area is covered by the UN buffer zone. The international community considers the part of the island as territory of the Republic of Cyprus occupied by Turkish forces. The occupation is viewed as illegal under law, amounting to illegal occupation of EU territory since Cyprus became a member of the European Union. Cyprus is a major tourist destination in the Mediterranean, on 1 January 2008, the Republic of Cyprus joined the eurozone. The earliest attested reference to Cyprus is the 15th century BC Mycenaean Greek
William Smith (geologist)
William Strata Smith was an English geologist, credited with creating the first nationwide geological map. At the time his map was first published he was overlooked by the community, his relatively humble education. Consequently, his work was plagiarised, financially ruined, he spent time in debtors prison and it was only much in his life that Smith received recognition for his accomplishments, and became known as the Father of English Geology. Smith was born in the village of Churchill, the son of blacksmith John Smith and his father died when Smith was just eight years old, and he was raised by his uncle, called William Smith. Although largely self-educated, Smith was highly intelligent and observant, read widely from an early age, in 1787, he met and found work as an assistant for Edward Webb of Stow-on-the-Wold, Gloucestershire, a surveyor. He was quick to learn, and soon became proficient at the trade, in 1791, he travelled to Somerset to make a valuation survey of the Sutton Court estate, and building on earlier work in the same area by John Strachey.
He stayed in the area for the eight years, working first for Webb and for the Somersetshire Coal Canal Company. Smith worked at one of the older mines, the Mearns Pit at High Littleton, part of the Somerset coalfield. As he observed the rock layers at the pit, he realised that they were arranged in a predictable pattern and that the various strata could always be found in the same relative positions. Additionally, each particular stratum could be identified by the fossils it contained, furthermore, he noticed an easterly dip of the beds of rock—low near the surface, higher after the Triassic rocks. This would earn him the name Strata Smith and he developed methods for the identification of deposits of Fullers earth to the south of Bath. He published his findings with many pictures from his collection, enabling others to investigate their distribution. His collection is good on Jurassic fossils he collected from the Cornbrash, Kimmeridge clay, Oxford clay, Oolitic limestone. They included many types of brachiopods and molluscs characteristic of the seas in which they were deposited.
Some of the names he coined are still used today for this formation, in 1799 Smith produced the first large scale geologic map of the area around Bath, Somerset. Previously, he knew how to draw the vertical extent of the rocks. However, in the Somerset County Agricultural Society, he found a map showing the types of soils and vegetation around Bath, the differing types were coloured. Using this technique, Smith could draw a map from his observations showing the outcrops of the rocks
Carbonate minerals
IMA-CNMNC proposes a new hierarchical scheme. This list uses the Classification of Nickel–Strunz
Permian
The Permian is a geologic period and system which spans 46.7 million years from the end of the Carboniferous Period 298.9 million years ago, to the beginning of the Triassic Period 252.2 Mya. It is the last period of the Paleozoic Era, the following Triassic Period belongs to the Mesozoic Era, the concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the city of Perm. The Permian witnessed the diversification of the early amniotes into the groups of the mammals, lepidosaurs. The world at the time was dominated by two known as Pangaea and Siberia, surrounded by a global ocean called Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior, who could better cope with these drier conditions, rose to dominance in place of their amphibian ancestors. The Permian ended with the Permian–Triassic extinction event, the largest mass extinction in Earths history, in which nearly 90% of marine species and it would take well into the Triassic for life to recover from this catastrophe.
Recovery from the Permian-Triassic extinction event was protracted, on land, the term Permian was introduced into geology in 1841 by Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil, the region now lies in the Perm Krai of Russia. This could have in part caused the extinctions of marine species at the end of the period by severely reducing shallow coastal areas preferred by many marine organisms. During the Permian, all the Earths major landmasses were collected into a supercontinent known as Pangaea. The Cimmeria continent rifted away from Gondwana and drifted north to Laurasia, a new ocean was growing on its southern end, the Tethys Ocean, an ocean that would dominate much of the Mesozoic Era. Large continental landmass interiors experience climates with extreme variations of heat and cold, deserts seem to have been widespread on Pangaea. Such dry conditions favored gymnosperms, plants with seeds enclosed in a cover, over plants such as ferns that disperse spores in a wetter environment.
The first modern trees appeared in the Permian, the climate in the Permian was quite varied. At the start of the Permian, the Earth was still in an Ice Age, glaciers receded around the mid-Permian period as the climate gradually warmed, drying the continents interiors. In the late Permian period, the drying continued although the temperature cycled between warm and cool cycles, Permian marine deposits are rich in fossil mollusks and brachiopods. By the close of the Permian, trilobites and a host of other groups became extinct. Terrestrial life in the Permian included diverse plants, arthropods, the period saw a massive desert covering the interior of Pangaea
Fossil
Fossils are the preserved remains or traces of animals and other organisms from the remote past. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous rock formations and sedimentary layers is known as the fossil record. The study of fossils across geological time, how they were formed, such a preserved specimen is called a fossil if it is older than some minimum age, most often the arbitrary date of 10,000 years. The observation that fossils were associated with certain rock strata led early geologists to recognize a geological timescale in the 19th century. The development of dating techniques in the early 20th century allowed geologists to determine the numerical or absolute age of the various strata. Like extant organisms, fossils vary in size from microscopic, even single bacterial cells one micrometer in diameter, to gigantic, such as dinosaurs, Fossils may consist of the marks left behind by the organism while it was alive, such as animal tracks or feces.
These types of fossil are called trace fossils, as opposed to body fossils, past life leaves some markers that cannot be seen but can be detected in the form of biochemical signals, these are known as chemofossils or biosignatures. The process of fossilization varies according to type and external conditions. Permineralization is a process of fossilization that occurs when an organism is buried, the empty spaces within an organism become filled with mineral-rich groundwater. Minerals precipitate from the groundwater, occupying the empty spaces and this process can occur in very small spaces, such as within the cell wall of a plant cell. Small scale permineralization can produce very detailed fossils, for permineralization to occur, the organism must become covered by sediment soon after death or soon after the initial decay process. The degree to which the remains are decayed when covered determines the details of the fossil, some fossils consist only of skeletal remains or teeth, other fossils contain traces of skin, feathers or even soft tissues.
This is a form of diagenesis, in some cases the original remains of the organism completely dissolve or are otherwise destroyed. The remaining organism-shaped hole in the rock is called an external mold, if this hole is filled with other minerals, it is a cast. An endocast or internal mold is formed when sediments or minerals fill the cavity of an organism. This is a form of cast and mold formation. If the chemistry is right, the organism can act as a nucleus for the precipitation of minerals such as siderite, if this happens rapidly before significant decay to the organic tissue, very fine three-dimensional morphological detail can be preserved. Nodules from the Carboniferous Mazon Creek fossil beds of Illinois, USA, are among the best documented examples of such mineralization, replacement occurs when the shell, bone or other tissue is replaced with another mineral
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