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Laventan
The Laventan ( es, Laventense) age is a period of geologic time (13.8 to 11.8 Ma) within the Middle Miocene epoch of the Neogene, used more specifically within the SALMA classification in South America. It follows the Colloncuran and precedes the Mayoan age.Madden et al., 1997 Etymology The age is named after the Miocene Lagerstätte La Venta, where a rich biodiversity from the Middle Miocene has been recovered from the Honda Group. Formations Fossil content Correlations The Laventan (13.8 to 11.8 Ma) correlates with: * NALMA ** latest Barstovian (15.97-13.65 Ma)Barstovian at Fossilworks.org ** early |
Honda Group, Colombia
The Honda Group ( es, Grupo Honda, Tsh, Ngh) is a geological group of the Upper and Middle Magdalena Basins and the adjacent Central and Eastern Ranges of the Colombian Andes. The group, in older literature also defined as formation, is in its present-day type section in the Tatacoa Desert in the department of Huila subdivided into two main formations; La Victoria and Villavieja. The group was originally defined in and named after Honda, Tolima, but has been redefined based on the many fossil finds in the Tatacoa Desert, to the south. In the original type section of its occurrence, the thick group is subdivided into three formations, from old to young; Cambrás, San Antonio and Los Limones. The group dates to the Neogene period; in its broadest definition from the Late Oligocene to Late Miocene, and in the redefined type section restricted to the Laventan age of the South American Land Mammal Ages (SALMA), equivalent to the Middle Miocene Serravallian epoch. The Honda Gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pisco Formation
The Pisco Formation is a geologic formation located in Peru, on the southern coastal desert of Ica, Peru, Ica and Arequipa. The approximately thick formation was deposited in the Pisco Basin, spanning an age from the Miocene, Middle Miocene up to the Early Pleistocene, roughly from 15 to 2 Ma. The tuffaceous sandstones, diatomaceous siltstones, Conglomerate (geology), conglomerates and dolomite (rock), dolomites were deposited in a lagoonal to near-shore depositional environment, environment, in bays similar to other Pacific South American formations as the Caldera Basin, BahÃa Inglesa and Coquimbo Formations of Chile. Several specialists consider the Pisco Formation one of the most important Lagerstätten,Brand et al., 2004Brand et al., 2011 based on the large amount of exceptionally preserved marine fossils, including sharks (most notably megalodon), penguins, whales, dolphins, birds, marine crocodiles and aquatic giant sloths. Famous fossils found in these layers include the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pebas Formation
The Pebas Formation is a lithostratigraphic unit of Miocene age, found in western Amazonia. The formation extends over , including parts of Brazil, Peru, Ecuador and Colombia.Wesselingh et al., 2006 It is interpreted as representing the deposits of a lake ("Lake Pebas") or series of lakes, formed within the foreland basin of the Andes mountain belt. It is known for its abundant fossil ostracods and molluscs and an unusually diverse group of crocodylians.Sala Gismondi et al., 2006 Fossil content Correlations Laventan Huayquerian References Bibliography * * * Further reading * {{cite LSA , first=P. , last=Antoine , first2=J.A. , last2=Abello , first3=S. , last3=Adnet , first4=A.J. , last4=Altamirano Sierra , first5=P. , last5=Baby , first6=G. , last6=Billet , first7=M. , last7=Boivin , first8=Y. , last8=Calderón , last9=Candela and J. Chabain, F. Corfu, D. A. Croft, M. Ganerød, C. Jaramillo, S. Klaus, L. Marivaux, R. E. Navarrete, M. J. Orliac, F. Par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South American Land Mammal Age
The South American land mammal ages (SALMA) establish a geologic timescale for prehistoric South American fauna beginning 64.5 Mya (unit), Ma during the Paleocene and continuing through to the Late Pleistocene (0.011 Ma). These periods are referred to as ages, stages, or intervals and were established using geographic place names where fossil materials where obtained.Flynn & Swisher, 1995 The basic unit of measure is the first/last boundary statement. This shows that the first appearance event of one taxon is known to predate the last appearance event of another. If two taxa are found in the same fossil quarry or at the same stratigraphic horizon, then their age-range zones overlap. Background South America was an island continent for much of the Cenozoic, or the "Age of Mammals". As a result, its mammals evolved in their own unique directions, as Australia and Madagascar still have today. Paleogeographic timeline A simplified paleogeography, paleogeographic timeline of South ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cura-MallÃn Group
Cura-MallÃn Group ( es, Grupo Cura-MallÃn) is a heterogeneous group of volcano-sedimentary formations of Oligocene-Miocene age, Colhuehuapian to Laventan in the SALMA classification, in south-central Chile and nearby parts of Argentina.Pedroza et al., 2017 The sediments belonging to the group were deposited in a lacustrine environment and alongside rivers in an intra-arc basin.Suárez & Emparan, 1995 Southeast of Laguna del Laja Cura-MallÃn Group has a thickness of more than . The sediments making up the group deposited in an interval between 22 and 8 million years ago. The outcrops of Cura-MallÃn Group are found along a north-south elongate area. The group is considered an equivalent of Abanico Formation, either as a southern extension or as a lateral equivalent of that formation.Flynn et al., 2008 Stratigraphy and members Various subdivision schemes have been proposed for the Cura-MallÃn unit since the 1980s. In 1983, Niemeyer and Muñoz identified two members; the Rà ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
La Venta (Colombia)
La Venta is a fossil locality located in the modern departments of Tolima and Huila in Colombia. This site is one of the richest Neogene fossil assemblages in South America and represents the best-known Cenozoic fossil site outside of Argentina. It provides a glimpse of what life in the region was like before the main wave of the Great American Interchange. Geology The fossils occur in Middle Miocene rocks of the Honda Group, which is divided into the younger Villavieja Formation and the older La Victoria Formation. The La Venta fauna contained ancient species of animal genera and families still alive today, as well as some entirely extinct prehistoric lineages. These animals lived some 13.8 to 12 million years ago in the Laventan age, which was named after La Venta. At that time, the climate of the region was wetter than today and there was much forest of trees similar (and probably related) to the ''sapino'' (''Goupia glabra'') of our time. List of fauna Fossil animals f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colloncuran
The Colloncuran ( es, Colloncurense) age is a period of geologic time (15.5–13.8 Ma) within the Middle Miocene epoch of the Neogene, used more specifically within the SALMA classification in South America. It follows the Friasian and precedes the Laventan age. Etymology The age is named after the Collón Curá Formation in the Cañadón Asfalto and Neuquén Basins of northern Patagonia, Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th .... Formations Fossils References Bibliography ;Collón Curá Formation * * * * * * * * * * * * * * * * * * * * * * * * * * * ;Castilletes Formation * * * * * * * * ;Cura-MallÃn Group * * * ;Gran Bajo del Gualicho Formation * ;Nazareno Formation * * * * ;Pebas Formation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mayoan
The Mayoan ( es, Mayoense) age is a period of geologic time from 11.8 to 10 Ma, within the Middle to Late Miocene epoch of the Neogene, used more specifically within the SALMA classification in South America. It follows the Laventan and precedes the Chasicoan age. Etymology The age is named after the RÃo Mayo Formation in the Golfo San Jorge Basin of Patagonia Patagonia () refers to a geographical region that encompasses the southern end of South America, governed by Argentina and Chile. The region comprises the southern section of the Andes Mountains with lakes, fjords, temperate rainforests, and gl ..., Argentina. Formations Fossil content References Bibliography ;RÃo Mayo Formation * ;Coquimbo Formation * ;Gran Bajo del Gualicho Formation * ;Huaylas Formation * * ;Mauri Formation * ;Navidad Formation * ;Paraná Formation * * ;Pebas Formation * * ;Pisco Formation * * * * * * * * * * * * * * ;Puerto Madryn Formation * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Time
The geologic time scale, or geological time scale, (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronology (scientific branch of geology that aims to determine the age of rocks). It is used primarily by Earth scientists (including geologists, paleontologists, geophysicists, geochemists, and paleoclimatologists) to describe the timing and relationships of events in geologic history. The time scale has been developed through the study of rock layers and the observation of their relationships and identifying features such as lithologies, paleomagnetic properties, and fossils. The definition of standardized international units of geologic time is the responsibility of the International Commission on Stratigraphy (ICS), a constituent body of the International Union of Geological Sciences (IUGS), whose primary objective is to precisely define ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Altiplano Basin
The Altiplano Basin ( es, Cuenca del Altiplano) is a sedimentary basin within the Andes in Bolivia and Peru. The basin is located on the Altiplano plateau between the Cordillera Occidental and the Cordillera Oriental. Over-all the basin has evolved through time in a context of horizontal shortening of Earth's crust. The great thickness of the sediments accumulated in the basin is mostly the result of the erosion of Cordillera Oriental. Description The Altiplano Basin has an approximate area of . The northern part of the basin is overridden by the Cordillera Occidental along the Pasani Fault, a thrust fault. To the east, the northern part of the basin was overridden by the Cordillera Oriental along the Ayaviri Fault, another thrust fault albeit the fault is now buried under more recent sediments. Further south near Oruro and Sica Sica the boundary of the basin with the Cordillera Oriental block is made up by the largely buried Coniri Fault. The fault contact is not reflected ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
