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<正>A new boreopterid pterosaur:Zhenyuanopterus longirostris gen.et sp.nov.from the Yixian Formation of western Liaoning is erected,based on the complete skeleton with a skull and lower jaws preserved.It is characterized by:a large boreopterid pterosaur with a high number of teeth,where the anterior teeth are much larger than posterior ones;the length of the dorsal + sacral vertebrae is nearly half the length of the skull;ratio of the length of the humerus to metacarpal IV is approximately 91%and the,humerus,femur and third wing phalanx are all equal in length and the feet are specially small.It represents the largest boroepterid pterosaur discovered from western Liaoning and its surrounding areas so far  相似文献   
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The XIV IGC was held in Spain in 1926, marking a recovery trend in the Congress after the First Worm War in terms of the number of participants and the number of represented countries. It was Spain that benefited most from the XIV IGC and probably never again there has geology received so much public and official attention.This paper is one of a series of articles on the history of the International Congress.  相似文献   
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RudolfTr&#;mpy 《《幕》》2004,27(3):195-198
The International Geological Congresses (IGCs) had been interrupted for nine years during World War I, between Toronto (1913)and Brussels (1922). World War II caused an even longer break of eleven years, between Moscow (1937) and London (1948).  相似文献   
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An increasing number of geologists in South America have turned their attention to isotope geology as a tool in the wider context of the Earth Sciences. As a result, a series of symposia on the South American isotope geology (SSAGI) has been organized every two years to provide an appropriate forum for discussion of methods and applications of stable and radiogenic isotopes.  相似文献   
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In the Diego de Almagro archipelago of southern Chile, a quartz rich mica schist and a mylonitized granite contain Late Jurassic zircons of ca 166 and 170 Ma respectively. These rocks were metamorphosed during the Cretaceous in a subduction zone environment, which developed blueschist assemblages in metabasalts interleaved with the mica schist. The dated rocks were probably part of the acid large igneous province developed in southwestern Gondwanaland during the extensional phase which preceded the dismembering of the supercontinent. They constitute evidence that tectonic erosion of the margin occurred, as these siliceous igneous rocks, formed in the South American upper plate, were transported in the subduction zone to some 20 km depth prior to their exhumation. These rocks are in tectonic contact through the Seno Arcabuz shear zone, with late Permian turbidites of the Duque de York complex, which did not undergo blueschist metamorphism.  相似文献   
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The Gavd Neolithic Mining Complex (GNMC) near Barcelona was active during the Neolithic age, since ca. 6000 BP until about 700 years after. These mines show up to five different underground mining levels, developed as galleries and chambers, communicated through pits, drawing a complex network with a total known length of over 1000 m. These are some of the oldest underground mines in Europe but, contrary to the rest of the mine workings known of the same epoch, this is the only mining complex reported to date whose aim was not mining for conventional substances for the epoch such as chert, ochre or copper. The main aim of the GNMC was variscite, a green phosphate mineral similar to turquoise that can be easily cut and polished to make ornaments such as necklaces or bracelets. This paper is focused mainly on the geological mapping and examination in surface and underground exposures of the different phosphate mineralization types(stratabound and veins) and other relevant geological features such as discordances, thrusts, faults, and folds.  相似文献   
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