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Pseudofossils
Pseudofossils are inorganic objects, markings, or impressions that might be mistaken for fossils. Pseudofossils may be misleading, as some types of mineral deposits can mimic lifeforms by forming what appear to be highly detailed or organized structures. One common example is when manganese oxides crystallize with a characteristic tree-like or dendritic pattern along a rock fracture. The formation of frost dendrites on a window is another common example of this crystal growth. Concretions are sometimes thought to be fossils, and occasionally one contains a fossil, but are generally not fossils themselves. Chert or flint nodules in limestone can often take forms that resemble fossils. Background Pyrite disks or spindles are sometimes mistaken for fossils of sand dollars or other forms (see marcasite). Cracks, bumps, gas bubbles, and such can be difficult to distinguish from true fossils. Specimens that cannot be attributed with certainty to either fossils or pseudofossils are t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossilized
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of '' Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before print. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of '' Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before prin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dubiofossil
{{More citations needed, date=October 2021 The term dubiofossil is a portmanteau word used in geology and paleontology for a problematic structure that looks like a fossil but has an uncertain biologic origin. From Latin ''dubius'', and English fossil, the word has been used mainly for remains found in rocks dating from the early history of the Earth (Precambrian rocks), but it is also applicable in other settings such as problematic microbe-like forms in meteorites. Although ultimately such structures are either biogenic (i.e., fossil) or abiogenic (i.e., pseudofossil), the information available at the time of study is insufficient to make an unambiguous determination. They belong to the dubiofossil category temporarily, awaiting additional evidence that will allow them to be removed from this category and attributed to the fossils or the pseudofossils. For example, see ALH84001. Physical and chemical processes can produce structures that look indistinguishable from some that ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eozoön
''Eozoön canadense'' (literally, "dawn animal of Canada") is a pseudofossil. John William Dawson described the banded structures of coarsely crystalline calcite and serpentine as a gigantic Foraminifera, which was thought to be the oldest known fossil . It was found in Precambrian metamorphosed limestone of Canada, at Côte St. Pierre near Grenville (Quebec) in 1863. It was later found in several other localities. Dawson called it "one of the brightest gems in the scientific crown of the Geological Survey of Canada". In 1894, it was shown that the place where it was found was associated with metamorphism (; ). Similar Eozoön structures were subsequently found in metamorphosed limestone blocks erupted from Mount Vesuvius Mount Vesuvius ( ) is a Somma volcano, somma–stratovolcano located on the Gulf of Naples in Campania, Italy, about east of Naples and a short distance from the shore. It is one of several volcanoes forming the Campanian volcanic arc. Vesuv ..., wher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concretion
A concretion is a hard and compact mass formed by the precipitation of mineral cement within the spaces between particles, and is found in sedimentary rock or soil. Concretions are often ovoid or spherical in shape, although irregular shapes also occur. The word ''concretion'' is borrowed from Latin , itself derived from ''concrescere'' , from ''con-'' and ''crescere'' . Concretions form within layers of sedimentary strata that have already been deposited. They usually form early in the burial history of the sediment, before the rest of the sediment is hardened into rock. This concretionary cement often makes the concretion harder and more resistant to weathering than the host stratum. There is an important distinction to draw between concretions and nodules. Concretions are formed from mineral precipitation around some kind of nucleus while a nodule is a replacement body. Descriptions dating from the 18th century attest to the fact that concretions have long been regarde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Gardens
file:Chemical garden.jpg, Comparison of chemical gardens grown by NASA scientists on the International Space Station (left) and on the ground (right) file:Silicate garden growing 0001.ogv, A chemical garden while growing file:Silikatna bašta - kobalt - 002.jpg, upCobalt(II) chloride file:Silikatna bašta 2.JPG, upA chemical garden A chemical garden is a set of complex biological-looking structures created by mixing inorganic chemicals. This experiment in chemistry is usually performed by adding metal salts, such as copper sulfate or cobalt(II) chloride, to an aqueous solution of sodium silicate (otherwise known as waterglass). This results in the growth of plant-like forms in minutes to hours. The chemical garden was first observed and described by Johann Rudolf Glauber in 1646. In its original form, the chemical garden involved the introduction of ferrous chloride (FeCl2) crystals into a solution of potassium silicate (K2SiO3). Process The chemical garden relies on most tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene
The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene followed the Oligocene and preceded the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by distinct global events but by regionally defined transitions from the warmer Oligocene to the cooler Pliocene Epoch. During the Early Miocene, Afro-Arabia collided with Eurasia, severing the connection between the Mediterranean and Indian Oceans, and allowing the interchange of fauna between Eurasia and Africa, including the dispersal of proboscideans and Ape, hominoids into Eurasia. During the late Miocene, the conn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solnhofen
Solnhofen is a municipality in the district of Weißenburg-Gunzenhausen in the region of Middle Franconia in the ' of Bavaria in Germany. It is in the Altmühl valley. The local area is famous in geology and palaeontology for Solnhofen limestone. This is a very fine-grained limestone from the Jurassic period Lagerstätte that preserves detailed fossil specimens. Alois Senefelder used specially prepared blocks of the fine Solnhofen limestone for the process of lithography which he invented in 1798. The quarrying of this lithographic limestone subsequently yielded spectacular finds, including '' Archaeopteryx'', commemorated in the bird's full name ''Archaeopteryx lithographica''. All 13 known specimens have come from the Solnhofen area. Geography Solnhofen is located on the Altmühl in Bavaria. It contains two districts: Hochholz and Eßlingen. It is adjacent to the municipalities Pappenheim, Langenaltheim, and Mörnsheim. History Solnhofen was known as "Husen" in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microorganisms
A microorganism, or microbe, is an organism of microscopic size, which may exist in its single-celled form or as a colony of cells. The possible existence of unseen microbial life was suspected from antiquity, with an early attestation in Jain literature authored in 6th-century BC India. The scientific study of microorganisms began with their observation under the microscope in the 1670s by Anton van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s, Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera, diphtheria, and anthrax. Microorganisms are extremely diverse, representing most unicellular organisms in all three domains of life: two of the three domains, Archaea and Bacteria, only contain microorganisms. The third domain, Eukaryota, includes all multicellular organisms as well as many unicellular protists and protozoans that ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungi
A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one of the kingdom (biology)#Six kingdoms (1998), traditional eukaryotic kingdoms, along with Animalia, Plantae, and either Protista or Protozoa and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of motility, mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Vesuvius
Mount Vesuvius ( ) is a Somma volcano, somma–stratovolcano located on the Gulf of Naples in Campania, Italy, about east of Naples and a short distance from the shore. It is one of several volcanoes forming the Campanian volcanic arc. Vesuvius consists of a large volcanic cone, cone partially encircled by the steep rim of a summit caldera, resulting from the collapse of an earlier, much higher structure. The eruption of Mount Vesuvius in 79 AD destroyed the Roman Empire, Roman cities of Pompeii, Herculaneum, Oplontis, Stabiae and other settlements. The eruption ejected a cloud of Volcanic rock, stones, Volcanic ash, ash and volcanic gases to a height of , Volcanic eruption, erupting Lava, molten rock and pulverized pumice at the rate of per second. More than 1,000 people are thought to have died in the eruption, though the exact toll is unknown. The only surviving witness account consists of two letters by Pliny the Younger to the historian Tacitus. Vesuvius has erupted ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone Block
Limestone is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for limestone co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
