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The laser ablation ICP–MS transect of a speleothem from GB Cave, close to Charterhouse, Mendip Hills, UK, records Pb variations over the past 5 ka. The speleothem record correlates well with the known historical record of lead mining in the district, the principal features of which include: the Roman lead mining peak; the Dark Ages cessation; gradual, episodic revival up to the late 16th century peak; the 17th century collapse and subsequent recovery; and the final short‐lived burst at the end of the 19th century. This correlation supports the assumption that the pre‐Roman lead record also derives from local mining. Thus, this record is the first example of quantifying ancient human mining activity through trace element signature of a speleothem. This record also provides the first solid evidence of significant pre‐Roman mining activity in the Charterhouse region, and the first solid dating of that activity. This pre‐Roman mining can be divided into three main peaks dated to 1800–1500 bc , 1100–800 bc and 350–0 bc .  相似文献   
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Early research suggests that examination of the microscopic internal structure is a valid method for distinguishing burned from unburned bone in the archaeological record. This study compares burned and unburned modern bones with archaeological bones from Sibudu Cave (ca. 60,000 years ago) and Cave of Hearths (over 200,000 years ago) to more fully describe the heat-induced histological changes to bone. We also explore the effects of diagenesis on those changes to determine if histological evidence of burning preserves through fossilisation and diagenetic processes and can be successfully used to identify ancient burning. Application of this technique can help in addressing various issues, including the origins of controlled use of fire and understanding animal butchery and disposal.  相似文献   
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Qesem Cave is a unique Middle Pleistocene, hominin-bearing site in Israel that contains a rich microvertebrate accumulation. The microvertebrates are highly unusual in that half of them are from small reptiles, and most of the reptiles are chameleons, which are otherwise rare in the fossil record. Analysis of the lower vertebrate component shows uniform taphonomic characteristics: on average 17.6% of specimens show evidence of corrosion (the vast majority light), and specimen breakage is between 4.9 and 12.0%, depending on metric. Charring is negligible. Most species are small (body mass <60 g). These taphonomic attributes do not vary in the studied portion of the stratigraphic profile, nor do they systematically vary between taxa. Thorough study of all skeletal parts suggests that most individuals probably entered the cave as whole animals; the only exception is the large glass lizard, Pseudopus, which is represented mostly by the tail. These taphonomic data suggest a Barn Owl as the predominant accumulator. However, natural history observations on Barn Owls and chameleons are strongly at odds with this actualistic inference: Barn Owls are nowhere recorded as a major predator on chameleons. We argue that a focus on extant, especially European, populations could distort our understanding of their feeding biology and is vulnerable to counterexample. We propose a scenario that harmonizes actualism and natural history. We further identify a possible owl roost in Qesem Cave, the first time such a roost has been identified in a collapsed cave setting. These conclusions may have conservation implications for chameleons. They also suggest that the hearth adjacent to the microvertebrate concentration was situated in the twilight zone.  相似文献   
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The appearance of portable artistic objects during the Upper Palaeolithic is characterised by a combination of a wide choice of techniques, use of different materials and a diversity of iconographic expression, with many objects made of bone and antler decorated with animal representations. Taphonomic and experimental approaches have been systematically applied in an effort to understand the technical and artistic procedures followed. In this study, we applied a new combination of 3-dimensional microscopy (focus variation optical microscope) and micro-CT scanning to the analysis of two Magdalenian engraved specimens: a reindeer antler from the site of Neschers (France), engraved with the partial image of a horse in left profile, and a horse metatarsal from Courbet Cave, Penne (France), engraved with a horse head also in left profile. Results of the analysis suggest that both the Neschers and Courbet Cave engravings had been prepared before being carved. The overall contours of the horse body/head were incised first, while anatomical features were added afterwards. In the Neschers case, the incision resulted from the repeated scratching of a previously made incision in order to enlarge the engraving, possibly reflecting the engraver's aesthetic sense. The combination of the techniques used in this study is applicable to fragile or unique archaeological specimens. Micro-CT scanning, in particular, provides non-invasive means for identifying engravings that are obscured by encrusted sediment. The application of these techniques can potentially open new avenues for the authentication, technical and gestural recognition and interpretation of incised forms and artistic creativity.  相似文献   
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This study aimed to further test the method, reported by St Pierre et al. (2009), to develop robust chronologies of deposits in limestone caves through U/Th (Uranium/Thorium or U-Series) dating of soda straw stalactites. The chronology of fossil bearing deposits at Blanche Cave was further constrained with thermal ionisation mass spectrometry (TIMS) U/Th dating of 17 additional soda straw stalactite samples, and results were compared to recalibrated 14C ages of charcoal. The results support the assertion that soda straw stalactites can provide ages close to the time of sediment deposition and may be used as reliable chronological markers, particularly for periods reaching or beyond the radiocarbon dating limit. The application of an enhanced cleaning technique facilitated the reduction of detrital Th in samples, significantly increasing age accuracy and precision. Additionally U/Th age accuracy and precision was increased through the application of site-specific measured U/Th ratios to correct for the detrital 230Th component in samples.  相似文献   
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The Middle Paleolithic industry of the Sibiryachikha facies is described on the basis of two stratified sites in the Altai – Okladnikov Cave (formerly Sibiryachikha) and Chagyrskaya Cave. Stratigrtraphic, environmental, and chronological aspects are discussed. The structure of two cave sites is analyzed. Petrographic properties of raw material are described and the typology and technology of the lithic industry are compared with those of other local Middle Paleolithic traditions. The Sibiryachikha facies of the Altai Middle Paleolithic represented by two sites was clearly associated with a small group of Neanderthals who migrated from western Central Asia. Eventually the Middle Paleolithic industry evolved into a local variant of the Upper Paleolithic.  相似文献   
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In 2010, the complete mitochondrial genome of a fossil hominin from Denisova Cave, Altai was sequenced on the basis of mtDNA extracted from the hand phalanx of a girl. Modern micro tomographic techniques mark a new stage in the morphological study of extant and fossil hominins, offering opportunities to work with fragmentary material. We have used the nondestructive method of micro computerized tomography for a comparative histological assessment of the Denisova girl's biological age. The diaphyseal and metaphyseal parts of the phalanx, reflecting different ontogenetic stages, were undergoing rapid growth. The histological pattern of the walls of the diaphysis, specifically the lamellar structure with rare osteons, indicates a stage corresponding to 6–7 years in modern children. An altogether different pattern, resembling that of adults, was earlier observed in a Neanderthal child from Okladnikov Cave, Altai. The resemblance between the Denisova individual and extant humans in certain features of growth and skeletal maturation may point to the very early origin of the modern skeletal growth pattern. The Neanderthal pattern is quite distinct and may have originated after these hominins had branched off from the common stem.  相似文献   
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