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Princeton Chert
The Princeton Chert is a fossil locality in British Columbia, Canada, which comprises an anatomically preserved flora of Eocene Epoch age, with rich species abundance and diversity. It is located in exposures of the Allenby Formation on the east bank of the Similkameen River, south of the town of Princeton, British Columbia. History The Princeton Chert (Ashnola shale in older sources) and its fossils have been known since the 1950s, but have attracted increased attention in the late 1970 and on. This may be due to the rare type of silica permineralized fossil Lagerstätten found, which has preserved plants and animals in minute 3D detail, with exceptional internal cellular detail. This has meant anatomical descriptions and reconstruction of whole plants from isolated parts has been possible in many species. Few plant fossils elsewhere in the world exhibit such excellence in both preservation and diversity. Similar aged fossil beds in Eocene lake sediments are found elsewhere in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Princeton Chert Sequence
Princeton University is a private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth as the College of New Jersey, Princeton is the fourth-oldest institution of higher education in the United States and one of the nine colonial colleges chartered before the American Revolution. It is one of the highest-ranked universities in the world. The institution moved to Newark in 1747, and then to the current site nine years later. It officially became a university in 1896 and was subsequently renamed Princeton University. It is a member of the Ivy League. The university is governed by the Trustees of Princeton University and has an endowment of $37.7 billion, the largest endowment per student in the United States. Princeton provides undergraduate and graduate instruction in the humanities, social sciences, natural sciences, and engineering to approximately 8,500 students on its main campus. It offers postgraduate degrees through the Princeton School of Publi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous ( Pennsylvanian) and Permian times. Many significant coal deposits are younger than this and originate from the Mesozoic and Cenozoic eras. Coal is used primarily as a fuel. While coal has been known and used for thousands of years, its usage was limited until the Industrial Revolution. With the invention of the steam engine, coal consumption increased. In 2020, coal supplied about a quarter of the world's primary energy and over a third of its electricity. Some iron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Himalayas
The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over 100 peaks exceeding in elevation lie in the Himalayas. By contrast, the highest peak outside Asia (Aconcagua, in the Andes) is tall. The Himalayas abut or cross five countries: Bhutan, India, Nepal, China, and Pakistan. The sovereignty of the range in the Kashmir region is disputed among India, Pakistan, and China. The Himalayan range is bordered on the northwest by the Karakoram and Hindu Kush ranges, on the north by the Tibetan Plateau, and on the south by the Indo-Gangetic Plain. Some of the world's major rivers, the Indus, the Ganges, and the Tsangpo–Brahmaputra, rise in the vicinity of the Himalayas, and their combined drainage basin is home to some 600 million people; 53 million people live in the Himalayas. The Himalayas have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphic
Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causing profound physical or chemical changes. During this process, the rock remains mostly in the solid state, but gradually recrystallizes to a new texture or mineral composition. The protolith may be an igneous, sedimentary, or existing metamorphic rock. Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface. They are classified by their protolith, their chemical and mineral makeup, and their texture. They may be formed simply by being deeply buried beneath the Earth's surface, where they are subject to high temperatures and the great pressure of the rock layers above. They can also form from tectonic processes such as continental collisions, which cause horizontal pressure, friction, and distorti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene Thermal Maximum 2
Eocene Thermal Maximum 2 (ETM-2), also called H-1 or the Elmo (Eocene Layer of Mysterious Origin) event, was a transient period of global warming that occurred around either 54.09 Ma or 53.69 Ma. It appears to be the second major hyperthermal that punctuated the long-term warming trend from the Late Paleocene through the early Eocene (58 to 50 Ma). The hyperthermals were geologically brief time intervals (<200,000 years) of global warming and massive input of isotopically light carbon into the atmosphere. The most extreme and best-studied event, the Paleocene-Eocene Thermal Maximum (PETM or ETM-1), occurred about 1.8 million years before ETM-2, at approximately 55.5 Ma. Other hyperthermals likely followed ETM-2 at nominally 53.6 Ma (H-2), 53.3 (I-1), 53.2 (I-2) and 52.8 Ma (informally called K, X or ETM-3). The number, nomencla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climate
Climate is the long-term weather pattern in an area, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteorological variables that are commonly measured are temperature, humidity, atmospheric pressure, wind, and precipitation. In a broader sense, climate is the state of the components of the climate system, including the atmosphere, hydrosphere, cryosphere, lithosphere and biosphere and the interactions between them. The climate of a location is affected by its latitude/longitude, terrain, altitude, land use and nearby water bodies and their currents. Climates can be classified according to the average and typical variables, most commonly temperature and precipitation. The most widely used classification scheme was the Köppen climate classification. The Thornthwaite system, in use since 1948, incorporates evapotranspiration along with temperature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Eocene
In the geologic timescale the Ypresian is the oldest age or lowest stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by the Eocene Lutetian Age. The Ypresian is consistent with the lower Eocene. Events The Ypresian Age begins during the throes of the Paleocene–Eocene Thermal Maximum (PETM). The Fur Formation in Denmark, the Messel shales in Germany, the Oise amber of France and Cambay amber of India are of this age. The Eocene Okanagan Highlands are an uplands subtropical to temperate series of lakes from the Ypresian. Stratigraphic definition The Ypresian Stage was introduced in scientific literature by Belgian geologist André Hubert Dumont in 1850. The Ypresian is named after the Flemish city of Ypres in Belgium (spelled ''Ieper'' in Dutch). The definitions of the original stage were totally different from the modern ones. The Ypresian shares its name with the Belgian Ieper Group (French: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ypresian
In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by the Eocene Lutetian Age. The Ypresian is consistent with the lower Eocene. Events The Ypresian Age begins during the throes of the Paleocene–Eocene Thermal Maximum (PETM). The Fur Formation in Denmark, the Messel shales in Germany, the Oise amber of France and Cambay amber of India are of this age. The Eocene Okanagan Highlands are an uplands subtropical to temperate series of lakes from the Ypresian. Stratigraphic definition The Ypresian Stage was introduced in scientific literature by Belgium, Belgian geologist André Hubert Dumont in 1850. The Ypresian is named after the Flanders, Flemish city of Ypres in Belgium (spelled ''Ieper'' in Dutch). The definitions of the original stage were totally different from the modern ones. The Ypresi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiometric Dating
Radiometric dating, radioactive dating or radioisotope dating is a technique which is 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, which form at a known constant rate of decay. The use of radiometric dating was first published in 1907 by Bertram Boltwood and is now the principal source of information about the absolute age of rocks and other geological features, including the age of fossilized life forms or the age of Earth itself, and can also be used to date a wide range of natural and man-made materials. Together with stratigraphic principles, radiometric dating methods are used in geochronology to establish the geologic time scale. Among the best-known techniques are radiocarbon dating, potassium–argon dating and uranium–lead dating. By al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammals
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or hair, and three middle ear bones. These characteristics distinguish them from reptiles (including birds) from which they diverged in the Carboniferous, over 300 million years ago. Around 6,400 extant species of mammals have been described divided into 29 orders. The largest orders, in terms of number of species, are the rodents, bats, and Eulipotyphla (hedgehogs, moles, shrews, and others). The next three are the Primates (including humans, apes, monkeys, and others), the Artiodactyla ( cetaceans and even-toed ungulates), and the Carnivora (cats, dogs, seals, and others). In terms of cladistics, which reflects evolutionary history, mammals are the only living members of the Synapsida (synapsids); this clade, together with Saur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Outcrop
An outcrop or rocky outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth. Features Outcrops do not cover the majority of the Earth's land surface because in most places the bedrock or superficial deposits are covered by soil and vegetation and cannot be seen or examined closely. However, in places where the overlying cover is removed through erosion or tectonic uplift, the rock may be exposed, or ''crop out''. Such exposure will happen most frequently in areas where erosion is rapid and exceeds the weathering rate such as on steep hillsides, mountain ridges and tops, river banks, and tectonically active areas. In Finland, glacial erosion during the last glacial maximum (ca. 11000 BC), followed by scouring by sea waves, followed by isostatic uplift has produced many smooth coastal and littoral outcrops. Bedrock and superficial deposits may also be exposed at the Earth's surface due to human excavations such as quarrying and build ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
