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Onverwacht Series
The Onverwacht Group or Onverwacht Series is a series of greenstone belts and volcanic rock formations from the Archean Eon in the Kaapvaal Craton in South Africa and Eswatini. A well known part of the Onverwacht Series is visible in the Komati River, Komati valley, located in the east of the Transvaal Province, Transvaal region. Subdivision The Onverwacht Group can be divided into two subgroups with six formations: * Geluk Subgroup ** Swartkoppie Formation – ** Kromberg Formation – ** Hooggenoeg Formation – * Tjakastad Subgroup ** Komatii Formation – ** Theespruit Formation – ** Sandspruit Formation – The fossils found in the Onverwacht Series are among the oldest found on Earth.Engel et al., 1968 See also * Archean life in the Barberton Greenstone Belt * Warrawoona Group References Bibliography * External links *Der Barberton Greenstone Belt und Komatiite Geologic groups of Africa Geologic formations of South Africa Geology of Eswatini A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleoarchean
The Paleoarchean (), also spelled Palaeoarchaean (formerly known as early Archean), is a Geologic time scale#Terminology, geologic era within the Archean, Archaean Eon. The name derives from Greek "Palaios" ''ancient''. It spans the period of time . The era is defined Absolute dating, chronometrically and is not referenced to a specific level of a rock section on Earth. The Abiogenesis, earliest confirmed evidence of life comes from this era, and Vaalbara, one of Earth's earliest Supercontinent, supercontinents, may have formed during this era. Early life The geological record from the Paleoarchean era is very limited. Due to deformation and metamorphism, most rocks from the Paleoarchean era cannot provide any useful information. There are only two locations in the world containing rock formations that are intact enough to preserve evidence of early life: the Kaapvaal Craton in Southern Africa and the Pilbara Craton in Western Australia. The Pilbara Craton, Dresser Formation, l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Eswatini
The geology of Eswatini formed beginning 3.6 billion years ago, in the Archean Eon of the Precambrian. Eswatini is the only country entirely underlain by the Kaapvaal Craton, one of the oldest pieces of stable continental crust and As such, the country has very ancient granite, gneiss and in some cases sedimentary rocks from the Archean into the Proterozoic, overlain by sedimentary rocks and igneous rocks formed during the last 539 million years of the Phanerozoic as part of the Karoo Supergroup. Intensive weathering has created thick zones of saprolite and heavily weathered soils. Stratigraphy and geologic history Eswatini is built on 3.6 to 2.5 billion year old Archean continental crust that forms the Kaapvaal Craton spanning into South Africa, northern Lesotho, western Mozambique, Botswana and southern Zimbabwe. The Precambrian rocks of Eswatini from this period are primarily gneiss and granite, formed between 3.4 and 2.6 billion years ago, based on rubidium-strontium dating an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Formations Of South Africa
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology, and so is treated as one major aspect of integrated 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. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists broadly study the properties and processes of E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Groups Of Africa
Geology () is a branch of natural science concerned with Earth and other Astronomical object, astronomical objects, the features or rock (geology), rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth science, Earth sciences, including hydrology, and so is treated as one major aspect of integrated 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. It also provides tools to determine the Relative dating, relative and Geochronology, absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Eart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science (journal)
''Science'', also widely referred to as ''Science Magazine'', is the peer-reviewed academic journal of the American Association for the Advancement of Science (AAAS) and one of the world's top academic journals. It was first published in 1880, is currently circulated weekly and has a subscriber base of around 130,000. Because institutional subscriptions and online access serve a larger audience, its estimated readership is over 400,000 people. ''Science'' is based in Washington, D.C., United States, with a second office in Cambridge, UK. Contents The major focus of the journal is publishing important original scientific research and research reviews, but ''Science'' also publishes science-related news, opinions on science policy and other matters of interest to scientists and others who are concerned with the wide implications of science and technology. Unlike most scientific journals, which focus on a specific field, ''Science'' and its rival ''Nature (journal), Nature'' c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warrawoona Group
The Warrawoona Group is a geological unit in Western Australia containing putative fossils of cyanobacteria cells. Dated 3.465 Ga, these microstructures, found in Archean chert, are considered to be the oldest known geological record of life on Earth. Description The fossils in this group were discovered by Arthur Hugh Hickman in 1983 in Warrawoona, , a region on the Pilbara craton in the northern part of Pilbara province. Whether or not the fossils are authentic was disputed in the past, as abiotic processes could not be ruled out. Currently the fossils are thought to be of biological origin, however there is no conclusive evidence of fossilized organisms in the formation, and whether the lines in the rock are fossilized stromatolites. The rocks also include felsic volcanic rocks. See also * North Pole, WA for similar issues * Origin of life * Timetable of the Precambrian * Geology of Australia The geology of Australia includes virtually all known rock types, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archean Life In The Barberton Greenstone Belt
The Barberton Greenstone Belt of eastern South Africa contains some of the most widely accepted fossil evidence for Archean life. These cell-sized prokaryote fossils are seen in the Barberton fossil record in rocks as old as 3.5 billion years. The Barberton Greenstone Belt is an excellent place to study the Archean Earth due to exposed sedimentary and metasedimentary rocks. Studying the earliest forms of life on Earth can provide valuable information to help understand how life can evolve on other planets. It has long been hypothesized that life may have existed on Mars due to the similarity of environmental and tectonic conditions during the Archean time. By knowing the environments in which early life evolved on Earth, and the rock types that preserve them, scientists can have a better understanding of where to look for life on Mars. Global beginnings of life Fossil life of 3.5 billion years of age is also found in the Pilbara craton of western Australia. This evidence, a ... [...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''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Komatii Formation
The Komati Formation, also named as Komatii Formation, is a 3.475 billion year old Paleoarchean rock formation, named after the nearby Komati River in South Africa. It is the type locality for komatiite, a high temperature, magnesium-rich volcanic rock occurring in the Barberton Greenstone Belt, Mpumalanga.18% MgO, high FeO, low potassium, and are composed ..., while the upper part is dominantly mafic.Guice, 2019, p.143 References Bibliography * * {{Geology of South Africa, formations Geologic formations of South Africa Archean Africa Paleoarchean volcanism Volcanism of South Africa Mining in South Africa Formations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
