|
Exogyra Costata Prairie Bluff Fm Maastrichtian
''Exogyra'' is an extinct genus of fossil marine oysters in the family Gryphaeidae, the foam oysters or honeycomb oysters. These bivalves were cemented by the more cupped left valve. The right valve is flatter, and the beak is curved to one side. ''Exogyra'' lived on solid substrates in warm seas during the Jurassic and Cretaceous periods. Taxonomy The former subgenus ''Exogyra'' (''Aetostreon'') Bayle, 1878, is sometimes considered a separate genus due to a lack of the fine set of parallel ribs (chomata) separated by pits on the inner surface of the valves (which is present in the nominate subgenus). Species Distribution Fossils of ''Exogyra'' have been found in:''Exogyra'' at .org [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. The Jurassic constitutes the second and middle period of the Mesozoic, Mesozoic Era as well as the eighth period of the Phanerozoic, Phanerozoic Eon and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic magmatic province, Central Atlantic Magmatic Province (CAMP). The beginning of the Toarcian Age started around 183 million years ago and is marked by the Toarcian Oceanic Anoxic Event, a global episode of Anoxic event, oceanic anoxia, ocean acidification, and elevated global temperatures associated with extinctions, likely caused by the eruption of the Kar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Heron Rastall
Robert Heron Rastall (November 8, 1871, Turnerdale Hall near Whitby, North Yorkshire – February 3, 1950) was a British geologist and petrologist. In 1946 he was awarded the Lyell Medal. Education and career Robert Heron Rastall was the eldest son of the Cambridge alumnus Herbert Augustus Henry Rastall (1847–1910) of the manor Turnerdale Hall near Whitby. After studying agricultural science and taking a diploma from the Royal Agricultural Society of England, Robert H. Rastall held an appointment as a staff member of the Tamworth Agricultural College and Training Farm, which was in operation from 1886 to 1914. In 1899 he matriculated at Christ's College, Cambridge. There he studied geology and graduated with a B.A. with 1903 and an M.A. in 1906. In London at Messrs. Wren and Gurney's, he was a lecturer in geology from 1903 to 1906 and from 1908 to 1909. From 1906 to 1913 he was a fellow of Christ's College, Cambridge. He was employed from 1910 to 1919 as an additional demonstrato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesozoic Animals Of Asia
The Mesozoic Era is the era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Periods. It is characterized by the dominance of archosaurian reptiles such as the dinosaurs, and of gymnosperms such as cycads, ginkgoaceae and araucarian conifers; a hot greenhouse climate; and the tectonic break-up of Pangaea. The Mesozoic is the middle of the three eras since complex life evolved: the Paleozoic, the Mesozoic, and the Cenozoic. The era began in the wake of the Permian–Triassic extinction event, the largest mass extinction in Earth's history, and ended with the Cretaceous–Paleogene extinction event, another mass extinction whose victims included the non-avian dinosaurs, pterosaurs, mosasaurs, and plesiosaurs. The Mesozoic was a time of significant tectonic, climatic, and evolutionary activity. The supercontinent Pangaea began to break apart into separate landmasses. The climate of the Mesozoic was varied, alternating between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous Africa
The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 77.1 million years, it is the ninth and longest geological period of the entire Phanerozoic. The name is derived from the Latin , 'chalk', which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation . The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was largely ice-free, although there is some evidence of brief periods of glaciation during the cooler first half, and forests extended to the poles. Many of the dominant taxonomic groups present in modern times can be ultimately traced back to origins in the C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesozoic Animals Of Africa
The Mesozoic Era is the era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Periods. It is characterized by the dominance of archosaurian reptiles such as the dinosaurs, and of gymnosperms such as cycads, ginkgoaceae and araucarian conifers; a hot greenhouse climate; and the tectonic break-up of Pangaea. The Mesozoic is the middle of the three eras since complex life evolved: the Paleozoic, the Mesozoic, and the Cenozoic. The era began in the wake of the Permian–Triassic extinction event, the largest mass extinction in Earth's history, and ended with the Cretaceous–Paleogene extinction event, another mass extinction whose victims included the non-avian dinosaurs, pterosaurs, mosasaurs, and plesiosaurs. The Mesozoic was a time of significant tectonic, climatic, and evolutionary activity. The supercontinent Pangaea began to break apart into separate landmasses. The climate of the Mesozoic was varied, alternating between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous Bivalves
The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 77.1 million years, it is the ninth and longest geological period of the entire Phanerozoic. The name is derived from the Latin , 'chalk', which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation . The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was largely ice-free, although there is some evidence of brief periods of glaciation during the cooler first half, and forests extended to the poles. Many of the dominant taxonomic groups present in modern times can be ultimately traced back to origins in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic Bivalves
The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. The Jurassic constitutes the second and middle period of the Mesozoic Era as well as the eighth period of the Phanerozoic Eon and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic Magmatic Province (CAMP). The beginning of the Toarcian Age started around 183 million years ago and is marked by the Toarcian Oceanic Anoxic Event, a global episode of oceanic anoxia, ocean acidification, and elevated global temperatures associated with extinctions, likely caused by the eruption of the Karoo-Ferrar large igneous provinces. The end of the Jurassic, however, has no clear, definitive boundary with t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Bivalve Genera
Prehistory, also called pre-literary history, is the period of human history between the first known use of stone tools by hominins million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared years ago. It took thousands of years for writing systems to be widely adopted, with writing having spread to almost all cultures by the 19th century. The end of prehistory therefore came at different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. It is based on an old conception of history that without written records there could be no history. The most common conception today is that history is based on evidence, however the concept of prehistory hasn't been completely discarded. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colombian Geological Survey
The Colombian Geological Survey (CGS) (; formerly known as INGEOMINAS) is a scientific Government agency, agency of the Colombian government in charge of contributing to the socioeconomic development of the nation through research in basic and applied geosciences of the subsoil, the potential of its resources, evaluating and monitoring threats of geological origin, managing the geoscientific knowledge of the nation, and studying the nuclear and radioactive elements in Colombia. History The CGS was initially created as the ''National Scientific Commission'' () by the Congress of Colombia on December 22, in 1916, with the mission of mapping the geological resources of the nation and exploring the national territory in search of mineral deposits. Following a List of earthquakes in Colombia, series of earthquakes throughout the nation in the early 1920s, the eruption of the Galeras volcano in 1925, and the growing mining and petroleum industry, the Colombian government decided to re- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cordillera Oriental (Colombia)
The Cordillera Oriental () is the widest of the three branches of the Colombian Andes. The range extends from south to north, dividing from the Colombian Massif in Huila Department to Norte de Santander Department where it splits into the Serranía del Perijá and the Cordillera de Mérida in Venezuelan Andes. The highest peak is Ritacuba Blanco at in the Sierra Nevada del Cocuy. Geography The western part of the Cordillera Oriental belongs to the Magdalena River basin, while the eastern part includes the river basins of the Amazon River, Orinoco River, and Catatumbo River. Within it, the Altiplano Cundiboyacense and the Sierra Nevada del Cocuy (with the only snowy peaks in this mountain range) stand out. The mountain range contains the most páramos in the world. The Cordillera Oriental montane forests ecoregion An ecoregion (ecological region) is an ecological and geographic area that exists on multiple different levels, defined by type, quality, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chipaque Formation
The Chipaque Formation (, K2cp, Kc) is a geological formation of the Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The formation is also described as Gachetá Formation, named after Gachetá, in the area of the Llanos foothills of the Eastern Ranges. The predominantly organic shale formation dates to the Late Cretaceous period; Cenomanian-Turonian epochs and has a maximum thickness of . The formation, rich in TOC, is an important oil and gas generating unit for the giant oilfields Cupiagua and Cusiana of the Eastern Ranges as well as in the Llanos Orientales. Etymology The formation was named in 1931 as group and as formation in 1957 by Hubach after Chipaque, Cundinamarca.Montoya Arenas & Reyes Torres, 2005, p.26 Description Lithologies The Chipaque Formation has a maximum thickness of and is characterised by a sequence of pyritic organic shales, limestones and siltstones, with sandstone banks intercalated in the formation.Lobo Guerrero, 1992, p.4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
