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Deniliquin Multiple-ring Feature
The Deniliquin multiple-ring feature is a distinct deeply buried structure in southeast Australia. It is named after the town of Deniliquin. Its characteristics suggest that it is associated with an asteroid impact structure of diameter , which would make it the largest one on Earth, exceeding the largest verified one, the Vredefort impact structure of about in diameter. Description It is located beneath the Murray Basin, Murray Sedimentary Basin and partly beneath the Darling Sedimentary Basin, and centered about northwest of Deniliquin. The principal features of the Deniliquin structure are a multiple ring total magnetic intensity (TMI) pattern with the minimal TMI ring radius of ; a central quiet magnetic zone; circular Bouguer gravity patterns; an underlying Earth mantle, mantle Mohorovičić discontinuity, Moho rise about shallower than under the adjacent Tasman Orogen, Tasman orogenic zone; and radial faults associated with magnetic and demagnetized anomalies. The above ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deniliquin
Deniliquin () is a town in the western Riverina region of south-western New South Wales, Australia, close to the border with Victoria. It is the largest town in the Edward River Council local government area. Deniliquin is located at the intersection of the Riverina and Cobb Highway approximately south west of the state capital, Sydney and due north of Melbourne. The town is divided in two parts by the Edward River, an anabranch of the Murray River, with the main business district located on the south bank. The town services a productive agricultural district with prominent dairy, rice, wool and timber industries. At the , the urban population of Deniliquin was . Prehistory Deniliquin is the namesake of the deeply buried Deniliquin multiple-ring structure, which is suggested to be at the core of a 320 mile diameter impact structure formed by a meteor strike over 400 million years ago, possibly responsible for the Late Ordovician mass extinction. History Prior to Europe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multi-ring Impact Basin
A multi-ringed basin (also a multi-ring impact basin) is not a simple bowl-shaped crater, or a peak ring crater, but one containing multiple concentric topographic rings; a multi-ringed basin could be described as a massive impact crater, surrounded by circular chains of mountains resembling rings on a bull's-eye. A multi-ringed basin may have an area of many thousands of square kilometres. An impact crater of diameter bigger than about is referred to as a ''basin''. __TOC__ Structure More common peak ring craters have: (1) a peak-ring, i.e., a crater rim, which is generally circular, and; (2) a mountainous region which surrounds the center of the crater basin. In contrast, a multi-ringed basin has multiple peak-rings displaying as further concentric circles. In extremely large collisions, the rebound of the surface after impact can obliterate any trace of the initial impact point. Usually, a peak ring crater has a high structure with a terrace and has slump structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gondwana Research
''Gondwana Research'' is a peer-reviewed scientific journal with an "all earth science" scope and an emphasis on the origin and evolution of continents. It is part of the Elsevier Elsevier ( ) is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell (journal), Cell'', the ScienceDirect collection of electronic journals, ... group, published by Journal Center, China University of Geosciences Beijing, 29 Xueyuan Road, Beijing 100083, China. References External links * Geology journals Elsevier academic journals English-language journals {{Geology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australian Geographic
Australian Geographic is a media business that produces the ''Australian Geographic'' and Australian Geographic Adventure magazine, australiangeographic.com.au and operates, either itself or business partners, Australian Geographic stores, Australian Geographic Travel and various other businesses. ''Australian Geographic'' magazine, originally titled ''Dick Smith's Australian Geographic'', is a bi-monthly geographical journal created by Dick Smith in 1986. The magazine focuses mainly on stories about Australia, or about Australian people in other countries. The six editions published each year are available by subscription and on newsstands. They include posters or sheet maps in each edition, as well as photographs and detailed technical illustrations. The entire Australian Geographic magazine archive is available on its website to subscribers. The profits earned by Australian Geographic Holdings are contributed the Australian Geographic Society which is a registered Austr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Conversation (website)
''The Conversation'' is a network of nonprofit media outlets publishing news stories and research reports online, authored by academics with professional journalist editors to produce accessible research-informed outputs. Articles are written by academics and researchers under a Creative Commons license, allowing reuse without modification. Copyright terms for images are generally listed in the image caption and attribution. Its model has been described as explanatory journalism. Except in "exceptional circumstances", it only publishes articles by "academics employed by, or otherwise formally connected to, accredited institutions, including universities and accredited research bodies". The website was launched in Australia in March 2011. The network has since expanded globally with a variety of local editions originating from around the world. In September 2019, ''The Conversation'' reported a monthly online audience of 10.7 million users, and a combined reach o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tectonophysics
Tectonophysics, a branch of geophysics, is the study of the physical processes that underlie tectonic deformation. This includes measurement or calculation of the stress- and strain fields on Earth’s surface and the rheologies of the crust, mantle, lithosphere and asthenosphere. Overview Tectonophysics is concerned with movements in the Earth's crust and deformations over scales from meters to thousands of kilometers. These govern processes on local and regional scales and at structural boundaries, such as the destruction of continental crust (e.g. gravitational instability) and oceanic crust (e.g. subduction), convection in the Earth's mantle (availability of melts), the course of continental drift, and second-order effects of plate tectonics such as thermal contraction of the lithosphere. This involves the measurement of a hierarchy of strains in rocks and plates as well as deformation rates; the study of laboratory analogues of natural systems; and the construction o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Impact Craters On Earth
This list of impact structures (including impact craters) on Earth contains the majority of the 194+ confirmed impact structures given in the Earth Impact Database as of 2024. Alphabetical lists for different continents can be found under Impact structures by continent below. Unconfirmed structures can be found at List of possible impact structures on Earth. Confirmed impact structures listed by size and age These features were caused by the collision of meteors (consisting of large fragments of asteroids) or comets (consisting of ice, dust particles and rocky fragments) with the Earth. For eroded or buried craters, the stated diameter typically refers to the best available estimate of the original rim diameter, and may not correspond to present surface features. Time units are either in ka (thousands) or Ma (millions) of years. 10 ka or less Less than ten thousand years old, and with a diameter of or more. The EID lists fewer than ten such craters, and the largest in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Ordovician Mass Extinction
The Late Ordovician mass extinction (LOME), sometimes known as the end-Ordovician mass extinction or the Ordovician–Silurian extinction, is the first of the "big five" major mass extinction events in Earth's history, occurring roughly 445 million years ago (Ma). It is often considered to be the second-largest-known extinction event just behind the end-Permian mass extinction, in terms of the percentage of genera that became extinct. Extinction was global during this interval, eliminating 49–60% of marine genera and nearly 85% of marine species. Under most tabulations, only the Permian–Triassic mass extinction exceeds the Late Ordovician mass extinction in biodiversity loss. The extinction event abruptly affected all major taxonomic groups and caused the disappearance of one third of all brachiopod and bryozoan families, as well as numerous groups of conodonts, trilobites, echinoderms, corals, bivalves and graptolites. Despite its taxonomic severity, the Late Ordovician ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andean-Saharan Glaciation
The Hirnantian Glacial period, glaciation, also known as the Andean-Saharan glaciation, Early Paleozoic Ice Age (EPIA), the Early Paleozoic Icehouse, the Late Ordovician glaciation, or the end-Ordovician glaciation, occurred during the Paleozoic from approximately 460 annum, Ma to around 420 Ma, during the Late Ordovician and the Silurian period. The major glaciation during this period was formerly thought only to consist of the Hirnantian glaciation itself but has now been recognized as a longer, more gradual event, which began as early as the Darriwilian, and possibly even the Floian. Evidence of this glaciation can be seen in places such as Arabia, North Africa, South Africa, Brazil, Peru, Bolivia, Chile, Argentina, and Wyoming. More evidence derived from isotopic data is that during the Late Ordovician, tropical ocean temperatures were about 5 °C cooler than present day; this would have been a major factor that aided in the glaciation process. The Late Ordovician glaciati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gondwana
Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zealandia, Arabian Peninsula, Arabia, and the Indian subcontinent. Gondwana was formed by the Accretion (geology), accretion of several cratons (large stable blocks of the Earth's crust), beginning with the East African Orogeny, the collision of India and Geography of Madagascar, Madagascar with East Africa, and culminating in with the overlapping Brasiliano orogeny, Brasiliano and Kuunga orogeny, Kuunga orogenies, the collision of South America with Africa, and the addition of Australia and Antarctica, respectively. Eventually, Gondwana became the largest piece of continental crust of the Paleozoic Era, covering an area of some , about one-fifth of the Earth's surface. It fused with Laurasia during the Carboniferous to form Pan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orogenic Zone
An orogenic belt, orogen, or mobile belt, is a zone of Earth's crust affected by orogeny. An orogenic belt develops when a continental plate crumples and is uplifted to form one or more mountain ranges; this involves a series of geological processes collectively called ''orogenesis''. Overview Orogeny typically produces ''orogenic belts'', which are elongated regions of deformation bordering continental cratons. Young orogenic belts, in which subduction is still taking place, are characterized by frequent volcanic activity and earthquakes. Older orogenic belts are typically deeply eroded to expose displaced and deformed strata. These are often highly metamorphosed and include vast bodies of intrusive igneous rock called batholiths. File:Active Margin.svg, Subduction of an oceanic plate beneath a continental plate to form an accretionary orogen. (example: the Andes) File:Continental-continental convergence Fig21contcont.gif, Continental collision of two continental plates to for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid
An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). Asteroids are rocky, metallic, or icy bodies with no atmosphere, and are broadly classified into C-type asteroid, C-type (carbonaceous), M-type asteroid, M-type (metallic), or S-type asteroid, S-type (silicaceous). The size and shape of asteroids vary significantly, ranging from small rubble piles under a kilometer across to Ceres (dwarf planet), Ceres, a dwarf planet almost 1000 km in diameter. A body is classified as a comet, not an asteroid, if it shows a coma (tail) when warmed by solar radiation, although recent observations suggest a continuum between these types of bodies. Of the roughly one million known asteroids, the greatest number are located between the orbits of Mars and Jupiter, approximately 2 to 4 astronomical unit, AU ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
