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24-694: Cairngorm or Cairngorms may refer to: Places [ edit ] Cairngorm (Alberta) , a mountain in Jasper National Park, Canada Cairn Gorm , a mountain in the Scottish Highlands, after which the Cairngorms are named Cairngorm Mountain Railway Cairngorm Mountain ski resort , a ski and snowboarding recreation area on Cairn Gorm Cairngorms ,

48-438: A subarctic climate zone with cold, snowy winters, and mild summers. Winter temperatures can drop below −20 °C (−4 °F) with wind chill factors below −30 °C (−22 °F). Precambrian The Precambrian is an informal unit of geologic time, subdivided into three eons ( Hadean , Archean , Proterozoic ) of the geologic time scale . It spans from the formation of Earth about 4.6 billion years ago ( Ga ) to

72-616: A form of smoky quartz, found in the Cairngorms Cairngorm Brewery , a brewery in Aviemore, Scotland Cairngorm Club , a mountaineering club in Aberdeen, Scotland The Cairngorms (book} See also [ edit ] Cairn (disambiguation) Cairns (disambiguation) Loch Gorm Castle Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with

96-943: A mountain range in the Scottish Highlands Cairngorms National Park , a national park in Cairngorms, Scotland Cairngorm Lochs , a protected wetland area in the Cairngorms Cairngorm, a community in Strathroy-Caradoc , Ontario, Canada Cairngorm Lake , source of the Steel River (Ontario) , Canada Other [ edit ] Cairngorm (Flex framework) , one of the primary open-source software frameworks for application architecture in Adobe Flex Cairngorm (horse) (foaled 1902), an American Thoroughbred racehorse Cairngorm (mineral) ,

120-735: A possible 2450 Ma red alga from the Kola Peninsula , 1650 Ma carbonaceous biosignatures in north China, the 1600 Ma Rafatazmia , and a possible 1047 Ma Bangiomorpha red alga from the Canadian Arctic. The earliest fossils widely accepted as complex multicellular organisms date from the Ediacaran Period. A very diverse collection of soft-bodied forms is found in a variety of locations worldwide and date to between 635 and 542 Ma. These are referred to as Ediacaran or Vendian biota . Hard-shelled creatures appeared toward

144-736: Is a 2,610-metre (8,563 ft) mountain located in Alberta , Canada. Cairngorm is set within Jasper National Park , in the Victoria Cross Ranges of the Canadian Rockies . The town of Jasper is situated 10 kilometres (6.2 mi) to the southeast and Pyramid Mountain is 3.45 kilometres (2.14 mi) to the northeast. The peak is composed of sedimentary rock laid down from the Precambrian to

168-475: Is a fairly solid record of bacterial life throughout the remainder (Proterozoic Eon) of the Precambrian. Complex multicellular organisms may have appeared as early as 2100 Ma. However, the interpretation of ancient fossils is problematic, and "... some definitions of multicellularity encompass everything from simple bacterial colonies to badgers." Other possible early complex multicellular organisms include

192-604: Is known to occur during the RNA replication of extant coronaviruses . Evidence of the details of plate motions and other tectonic activity in the Precambrian is difficult to interpret. It is generally believed that small proto-continents existed before 4280 Ma, and that most of the Earth's landmasses collected into a single supercontinent around 1130 Ma. The supercontinent, known as Rodinia , broke up around 750 Ma. A number of glacial periods have been identified going as far back as

216-846: The Cairngorms , a mountain range in the Scottish Highlands associated with the mountain Cairn Gorm . Bridgland (1878–1948), was a Dominion Land Surveyor who named many peaks in Jasper Park and the Canadian Rockies. The mountain's toponym was officially adopted February 7, 1951, by the Geographical Names Board of Canada . Based on the Köppen climate classification , Cairngorm is located in

240-534: The Huronian epoch, roughly 2400–2100 Ma. One of the best studied is the Sturtian-Varangian glaciation, around 850–635 Ma, which may have brought glacial conditions all the way to the equator, resulting in a " Snowball Earth ". The atmosphere of the early Earth is not well understood. Most geologists believe it was composed primarily of nitrogen, carbon dioxide, and other relatively inert gases, and

264-592: The Jurassic periods which was pushed east and over the top of younger rock during the Laramide orogeny . Precipitation runoff from Cairngorm drains into tributaries of the Miette , Snaring and Athabasca rivers. Topographic relief is modest as the summit rises 1,430 meters (4,690 feet) above Pyramid Lake in six kilometers (3.7 miles). The mountain was named in 1916 by Morrison P. Bridgland after

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288-640: The Moon (see Giant-impact hypothesis ). A stable crust was apparently in place by 4,433 Ma, since zircon crystals from Western Australia have been dated at 4,404 ± 8 Ma. The term "Precambrian" is used by geologists and paleontologists for general discussions not requiring a more specific eon name. However, both the United States Geological Survey and the International Commission on Stratigraphy regard

312-482: The oxygen catastrophe . At first, oxygen would have quickly combined with other elements in Earth's crust, primarily iron, removing it from the atmosphere. After the supply of oxidizable surfaces ran out, oxygen would have begun to accumulate in the atmosphere, and the modern high-oxygen atmosphere would have developed. Evidence for this lies in older rocks that contain massive banded iron formations that were laid down as iron oxides. A terminology has evolved covering

336-546: The Precambrian (e.g. stromatolites ) are of limited biostratigraphic use. This is because many Precambrian rocks have been heavily metamorphosed , obscuring their origins, while others have been destroyed by erosion, or remain deeply buried beneath Phanerozoic strata. It is thought that the Earth coalesced from material in orbit around the Sun at roughly 4,543 Ma, and may have been struck by another planet called Theia shortly after it formed, splitting off material that formed

360-539: The beginning of the Cambrian Period, about 538.8 million years ago ( Ma ), when hard-shelled creatures first appeared in abundance. Relatively little is known about the Precambrian, despite it making up roughly seven-eighths of the Earth's history , and what is known has largely been discovered from the 1960s onwards. The Precambrian fossil record is poorer than that of the succeeding Phanerozoic , and fossils from

384-401: The current scheme based upon numerical ages. Such a system could rely on events in the stratigraphic record and be demarcated by GSSPs . The Precambrian could be divided into five "natural" eons, characterized as follows: The movement of Earth's plates has caused the formation and break-up of continents over time, including occasional formation of a supercontinent containing most or all of

408-505: The early years of the Earth's existence, as radiometric dating has allowed absolute dates to be assigned to specific formations and features. The Precambrian is divided into three eons: the Hadean (4567.3–4031 Ma), Archean (4031-2500 Ma) and Proterozoic (2500-538.8 Ma). See Timetable of the Precambrian . It has been proposed that the Precambrian should be divided into eons and eras that reflect stages of planetary evolution, rather than

432-760: The end of that time span, marking the beginning of the Phanerozoic Eon. By the middle of the following Cambrian Period, a very diverse fauna is recorded in the Burgess Shale , including some which may represent stem groups of modern taxa. The increase in diversity of lifeforms during the early Cambrian is called the Cambrian explosion of life. While land seems to have been devoid of plants and animals, cyanobacteria and other microbes formed prokaryotic mats that covered terrestrial areas. Tracks from an animal with leg-like appendages have been found in what

456-541: The landmass. The earliest known supercontinent was Vaalbara . It formed from proto-continents and was a supercontinent 3.636 billion years ago. Vaalbara broke up c. 2.845–2.803 Ga ago. The supercontinent Kenorland was formed c. 2.72 Ga ago and then broke sometime after 2.45–2.1 Ga into the proto-continent cratons called Laurentia , Baltica , Yilgarn craton and Kalahari . The supercontinent Columbia , or Nuna, formed 2.1–1.8 billion years ago and broke up about 1.3–1.2 billion years ago. The supercontinent Rodinia

480-523: The origin of life has not been determined. Carbon found in 3.8 billion-year-old rocks (Archean Eon) from islands off western Greenland may be of organic origin. Well-preserved microscopic fossils of bacteria older than 3.46 billion years have been found in Western Australia . Probable fossils 100 million years older have been found in the same area. However, there is evidence that life could have evolved over 4.280 billion years ago. There

504-592: The term as informal. Because the span of time falling under the Precambrian consists of three eons (the Hadean , the Archean , and the Proterozoic ), it is sometimes described as a supereon , but this is also an informal term, not defined by the ICS in its chronostratigraphic guide. Eozoic (from eo- "earliest") was a synonym for pre-Cambrian , or more specifically Archean . A specific date for

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528-506: The title Cairngorm . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Cairngorm&oldid=1130651581 " Categories : Disambiguation pages Place name disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Cairngorm (Alberta) Cairngorm

552-482: Was lacking in free oxygen . There is, however, evidence that an oxygen-rich atmosphere existed since the early Archean. At present, it is still believed that molecular oxygen was not a significant fraction of Earth's atmosphere until after photosynthetic life forms evolved and began to produce it in large quantities as a byproduct of their metabolism . This radical shift from a chemically inert to an oxidizing atmosphere caused an ecological crisis , sometimes called

576-852: Was mud 551 million years ago. The RNA world hypothesis asserts that RNA evolved before coded proteins and DNA genomes. During the Hadean Eon (4,567–4,031 Ma) abundant geothermal microenvironments were present that may have had the potential to support the synthesis and replication of RNA and thus possibly the evolution of a primitive life form. It was shown that porous rock systems comprising heated air-water interfaces could allow ribozyme - catalyzed RNA replication of sense and antisense strands that could be followed by strand-dissociation, thus enabling combined synthesis, release and folding of active ribozymes. This primitive RNA replicative system also may have been able to undergo template strand switching during replication ( genetic recombination ) as

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