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Baykonurian Glaciation
The Baykonurian glaciation is a glacial episode dating to around the Proterozoic–Phanerozoic boundary, at the end of the Ediacaran Period. The date of has been proposed in the literature. The glaciation is posited as a contributor to the Cambrian explosion. Its deposits are known in regions of Asia and Africa, and it apparently affected both palaeohemispheres. Glacial deposits possibly related to this glaciation have been found to be dated between 549 and 530 Ma. It is named for the Baykonur Formation in Central Asia Central Asia, also known as Middle Asia, is a subregion, region of Asia that stretches from the Caspian Sea in the west to western China and Mongolia in the east, and from Afghanistan and Iran in the south to Russia in the north. It includes t .... References Ice ages Ediacaran events {{Ediacaran-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proterozoic
The Proterozoic () is a geological eon spanning the time interval from 2500 to 538.8million years ago. It is the most recent part of the Precambrian "supereon". It is also the longest eon of the Earth's geologic time scale, and it is subdivided into three geologic eras (from oldest to youngest): the Paleoproterozoic, Mesoproterozoic, and Neoproterozoic. The Proterozoic covers the time from the appearance of oxygen in Earth's atmosphere to just before the proliferation of complex life (such as trilobites or corals) on the Earth. The name ''Proterozoic'' combines two forms of ultimately Greek origin: meaning 'former, earlier', and , 'of life'. The well-identified events of this eon were the transition to an oxygenated atmosphere during the Paleoproterozoic; the evolution of eukaryotes; several glaciations, which produced the hypothesized Snowball Earth during the Cryogenian Period in the late Neoproterozoic Era; and the Ediacaran Period (635 to 538.8 Ma) which is characterize ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phanerozoic
The Phanerozoic Eon is the current geologic eon in the geologic time scale, and the one during which abundant animal and plant life has existed. It covers 538.8 million years to the present, and it began with the Cambrian Period, when animals first developed hard shells preserved in the fossil record. The time before the Phanerozoic, called the '' Precambrian'', is now divided into the Hadean, Archaean and Proterozoic eons. The time span of the Phanerozoic starts with the sudden appearance of fossilised evidence of a number of animal phyla; the evolution of those phyla into diverse forms; the emergence and development of complex plants; the evolution of fish; the emergence of insects and tetrapods; and the development of modern fauna. Plant life on land appeared in the early Phanerozoic eon. During this time span, tectonic forces which move the continents had collected them into a single landmass known as Pangaea (the most recent supercontinent), which then separated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaran
The Ediacaran Period ( ) is a geological period that spans 96 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 538.8 Mya. It marks the end of the Proterozoic Eon, and the beginning of the Phanerozoic Eon. It is named after the Ediacara Hills of South Australia. The Ediacaran Period's status as an official geological period was ratified in 2004 by the International Union of Geological Sciences (IUGS), making it the first new geological period declared in 120 years. Although the period takes its name from the Ediacara Hills where geologist Reg Sprigg first discovered fossils of the eponymous Ediacaran biota in 1946, the type section is located in the bed of the Enorama Creek within Brachina Gorge in the Flinders Ranges of South Australia, at . The Ediacaran marks the first appearance of widespread multicellular fauna following the end of Snowball Earth glaciation events, the so-called Ediacaran biota, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian Explosion
The Cambrian explosion, Cambrian radiation, Cambrian diversification, or the Biological Big Bang refers to an interval of time approximately in the Cambrian Period when practically all major animal phyla started appearing in the fossil record. It lasted for about 13 – 25 million years and resulted in the divergence of most modern metazoan phyla. The event was accompanied by major diversification in other groups of organisms as well. Before early Cambrian diversification, most organisms were relatively simple, composed of individual cells, or small multicellular organisms, occasionally organized into colonies. As the rate of diversification subsequently accelerated, the variety of life became much more complex, and began to resemble that of today. Almost all present-day animal phyla appeared during this period, including the earliest chordates. A 2019 paper suggests that the timing should be expanded back to include the late Ediacaran, rather than just the n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baikonur
Baikonur ( kk, Байқоңыр, ; russian: Байконур, translit=Baykonur), formerly known as Leninsk, is a city of republic significance in Kazakhstan on the northern bank of the Syr Darya river. It is currently leased and administered by the Russian Federation as an enclave until 2050. It was constructed to service the Baikonur Cosmodrome and was officially renamed Baikonur by Russian president Boris Yeltsin on December 20, 1995. During the Soviet period, it was sometimes referred to as Zvezdograd (), Russian for ''Star City''. The rented area is an ellipse measuring east to west by north to south, with the cosmodrome situated at the area's centre. Foreign visitors need pre-approval from the Russian authorities to visit both the town of Baikonur itself and the Cosmodrome. Foreign visitors need to obtain a written approval which is completely separate from having a regular Russian visa. History The original Baikonur (Kazakh for "wealthy brown", i.e. "fertile land w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Formation
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by Abraham Gottlob Wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Asia
Central Asia, also known as Middle Asia, is a subregion, region of Asia that stretches from the Caspian Sea in the west to western China and Mongolia in the east, and from Afghanistan and Iran in the south to Russia in the north. It includes the former Soviet Union, Soviet republics of the Soviet Union, republics of Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan, which are colloquially referred to as the "-stans" as the countries all have names ending with the Persian language, Persian suffix "-stan", meaning "land of". The current geographical location of Central Asia was formerly part of the historic region of Turkestan, Turkistan, also known as Turan. In the pre-Islamic and early Islamic eras ( and earlier) Central Asia was inhabited predominantly by Iranian peoples, populated by Eastern Iranian languages, Eastern Iranian-speaking Bactrians, Sogdians, Khwarezmian language, Chorasmians and the semi-nomadic Scythians and Dahae. After expansion by Turkic peop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Geoscience Programme
The International Geoscience and Geoparks Programme (IGCP) is a cooperative enterprise of UNESCO The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations (UN) aimed at promoting world peace and security through international cooperation in education, arts, sciences and culture. It ... (the United Nations Educational, Scientific and Cultural Organization) and the International Union of Geological Sciences (IUGS). It was launched in 1972 and originally termed the ''International Geological Correlation Programme'', the source of the acronym IGCP which it retains. For decades the programme was known as the ''International Geoscience Programme''. In November 2015 the name was changed to ''International Geoscience and Geoparks Programme'' as the global geoparks were made part of the programme. The aim of the IGCP is to facilitate research cooperation among geoscientists across frontiers and national boundaries, through j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Ages
An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and greenhouse periods, during which there are no glaciers on the planet. Earth is currently in the Quaternary glaciation. Individual pulses of cold climate within an ice age are termed ''glacial periods'' (or, alternatively, ''glacials, glaciations, glacial stages, stadials, stades'', or colloquially, ''ice ages''), and intermittent warm periods within an ice age are called ''interglacials'' or ''interstadials''. In glaciology, ''ice age'' implies the presence of extensive ice sheets in both northern and southern hemispheres. By this definition, Earth is currently in an interglacial period—the Holocene. The amount of anthropogenic greenhouse gases emitted into Earth's oceans and atmosphere is predicted to prevent the next glacial period for the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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