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81.
2010年3~5月,贵州省文物考古研究所等单位对贵州省东部铜仁市锦江流域的磨刀湾、笔架冲、方田坝等遗址进行了发掘和试掘,此次工作是建国以来在贵州省锦江流域首次进行的系统考古发掘工作,获得了一批夏商、西周、两汉和宋明清时期的考古资料,具有重要的学术意义.本文着重介绍此次考古发掘中先秦时期遗存的主要收获,并对其学术意义展开初步讨论.  相似文献   
82.
土尔扈特蒙古西迁至伏尔加河流域后,其经济状况可以概括为:传统游牧经济由盛而衰;以互通有无为基础的对俄贸易往来不断;为俄国军事战役出兵助战获得战利品和报酬成为特殊的收入来源;突袭其他民族和控制贸易路线是增加财富的渠道之一;捕鱼成为相当一部分生活贫困的土尔扈特人赖以维持生计的重要方式。作者认为经济状况恶化是促使土尔扈特蒙古东归的原因之一。  相似文献   
83.
X. WANG  S. WU  S. YUAN  D. WANG  Y. MA  G. YAO  Y. GONG  G. ZHANG 《Geofluids》2010,10(3):351-368
Interpretation of high‐resolution two‐dimensional (2D) and three‐dimensional (3D) seismic data collected in the Qiongdongnan Basin, South China Sea reveals the presence of polygonal faults, pockmarks, gas chimneys and slope failure in strata of Pliocene and younger age. The gas chimneys are characterized by low‐amplitude reflections, acoustic turbidity and low P‐wave velocity indicating fluid expulsion pathways. Coherence time slices show that the polygonal faults are restricted to sediments with moderate‐amplitude, continuous reflections. Gas hydrates are identified in seismic data by the presence of bottom simulating reflectors (BSRs), which have high amplitude, reverse polarity and are subparallel to seafloor. Mud diapirism and mounded structures have variable geometry and a great diversity regarding the origin of the fluid and the parent beds. The gas chimneys, mud diapirism, polygonal faults and a seismic facies‐change facilitate the upward migration of thermogenic fluids from underlying sediments. Fluids can be temporarily trapped below the gas hydrate stability zone, but fluid advection may cause gas hydrate dissociation and affect the thickness of gas hydrate zone. The fluid accumulation leads to the generation of excess pore fluids that release along faults, forming pockmarks and mud volcanoes on the seafloor. These features are indicators of fluid flow in a tectonically‐quiescent sequence, Qiongdongnan Basin. Geofluids (2010) 10 , 351–368  相似文献   
84.
Symbolic or incomplete trephinations are very common in Hungary in 9th–11thcentury AD skeletal series connected to early Hungarians, although they also occur in the preceding Avar Age (6th–9th c. AD) material. During the compilation of a database of regional cranial modification data, the authors found rare almond‐shaped symbolic trephinations in both periods, while these had formerly only been reported in Early Hungarian series. In this study, the new almond‐shaped lesions are described along with other symbolic trephinations of 14 newly found skulls from the 8th–11thcenturies AD in the Southern Great Plain of Hungary. The authors review the research of the phenomenon. The new findings may strengthen the theory of direct and very close cultural connections of these two ethnic groups, adding a new aspect to the debate over the origin and relationship of Late Avar (late 7th–early 9th c. AD) and Early Hungarian (9th–11th c. AD) populations. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
85.
The period corresponding to the initial phase of cultural evolution in the Late Neolithic of SE Hungary (turn of the 6th and 5th millennia) is characterized by a major transformation recorded both in settlement structure and strategy, as well as material culture of the agrarian societies settled in the SE part of the Great Hungarian Plains. According to the available chronological data and archeology from the sites of multi-layered settlement complexes (tells) located on natural highs of the floodplain of the River Tisza, during the initial phase of its evolution representatives of the Tisza Culture were mainly confined to the SE part of the Great Hungarian Plains south of the Körös River. This period was followed by a relatively stable phase lasting about 150 years which hallmarked the greatest northward expansion of the culture. Some studies noticed strange features in connection with the first settlement complexes dated to the first period especially along the northern borderline of the culture’s distribution; i.e. a loose cluster of distinct settlement nuclei instead of concentration of settlements to a confined area characteristic of tells. Furthermore, by the end of the first phase, in the evolution of some settlements a northward shift of the houses away from the water was recorded. Most likely these reflect a socioeconomic response to some transformation in the local and/or regional riparian environment. As shown by our data gained from the paleoecological analysis of freshwater mollusks from a tell site, the referred pre-transitional period was characterized by pronounced floods causing major perturbations in the regional riparian environment. At the same time, the introduction of new subsistence strategies including shellfishing and fishing and the reordering of settlement structure was also recorded at several sites implying a successful adaptation to such most likely climate-induced perturbation, which is contemporary with the 5.1 ky event known in the literature.  相似文献   
86.
The inorganic and organic fractions of two microsamples of prehistoric paint from the same site, the Minateda rock shelters, are analysed here for the first time. The two samples correspond to two rock shelters of different styles (Levantine and schematic) – Abrigo Grande de Minateda (The Great Rock Shelter of Minateda) and Abrigo del Barranco de la Mortaja (Del Barranco de la Mortaja Rock Shelter). Since its discovery, historiographical tradition has emphasised the Abrigo Grande de Minateda, with its magnificence and complexity, as emblematic of the origin and evolution of rock art in the Mediterranean Basin of the Iberian Peninsula (a UNESCO World Heritage Site). Four complementary techniques –Microphotography, Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDX), Raman Spectroscopy and Gas Chromatography–Mass Spectroscopy (GC–MS)– were combined to identify and characterise the physicochemical properties of the paint and of the surface. We present an interpretation of the results that leads us to define complex taphonomic alterations beyond the usual distinction of layers that include the surface, pigments and patinas.  相似文献   
87.
On the west side of the Winnemucca Lake subbasin, Nevada, distinctive deeply carved meter-scale petroglyphs are closely spaced, forming panels on boulder-sized surfaces of a partially collapsed tufa mound. The large, complex motifs at this side are formed by deeply carved lines and cupules. A carbonate crust deposited between 10 200 and 9800 calibrated years B.P. (ka) coats petroglyphs at the base of the mound between elevations of 1202 and 1206 m. Petroglyphs above the carbonate crust are carved into a branching form of carbonate that dates to 14.8 ka. Radiocarbon dates on a multiple-layered algal tufa on the east side of the basin, which formed at an elevation of 1205 m, as well as a sediment-core-based total inorganic carbon record for the period 17.0–9.5 ka indicate that water level in the Winnemucca Lake subbasin was constrained by spill over the Emerson Pass Sill (1207 m) for most of the time between 12.9 ± 0.3 and ≥9.2 ka. These and other data indicate that the lake in the Winnemucca Lake subbasin fell beneath its spill point between 14.8 and 13.2 ka and also between 11.3 and 10.5 ka (or between 11.5 and 11.1 ka), exposing the base of the collapsed tufa mound to petroglyph carving. The tufa-based 14C record supports decreased lake levels between 14.8–13.2 ka and 11.3–10.5 ka. Native American artifacts found in the Lahontan Basin date to the latter time interval. This does not rule out the possibility that petroglyph carving occurred between 14.8 and 13.2 ka when Pyramid Lake was relatively shallow and Winnemucca Lake had desiccated.  相似文献   
88.
Great Basin populations during the Pleistocene–Holocene Transition (PHT) are often characterized as being mobile and focused on wetlands; however, the factors that influenced where Paleoindians selected residential campsites are poorly understood. Using predictions derived from optimal foraging-based patch choice models and GIS reconstructions of the PHT landscape, some researchers have argued that occupations in smaller wetlands should have been shorter than occupations in larger wetlands but such arguments have rarely been evaluated using empirical data. The PHT lithic record provides an opportunity to evaluate the relationship between wetland size and occupation span by applying Kuhn's (1995) concept of technological provisioning. Kuhn expects more mobile populations to provision individuals and more sedentary populations to provision places and suggests that: (1) a strategy of provisioning individuals should be reflected by a high proportion of more extensively used artifacts made on non-local raw materials; and (2) a strategy of provisioning places should be reflected by a high proportion of less extensively used artifacts made on local raw materials. We apply the technological provisioning concept to lithic assemblages from two of the Parman localities, extensive PHT sites in the northwestern Great Basin, and compare local and nonlocal artifacts to determine if Paleoindians shifted from provisioning individuals while moving to/from the sites to provisioning the place while occupying them. There is no relationship between artifact transport distance and artifact use intensity. We interpret these findings as evidence that Paleoindians did not alter their provisioning strategies while occupying the Parman localities, likely because occupations were brief within a small wetland poorly-suited to support groups for long periods.  相似文献   
89.
Palynological studies of Cenozoic sediments from borehole PGD-1A in the easternmost extension of the Damodar Basin, West Bengal, India, provide important new palynological data from this basin, where previous data are rare. The palynoassemblage includes Striatriletes, Crassoretitriletes, Bacutriporites, Cauveripollis, Cheilanthoidspora, Palaeomalvaceaepollis, Tricollareporites, Pinuspollenites and Tsugaepollenites which suggest a late Oligocene - early Miocene age. Dinocyst genera such as Selenopemphix, Tuberculodinium, Hystrichokoipoma and Thalasiphora, recorded from the borehole, also support this age assignment. The assemblage indicates a tropical to subtropical humid climate with high rainfall. Deposition of the studied strata took place in a delta under shallow marine influence; this is the first evidence that a marine transgression extended into the Damodar Basin and that mangrove forest developed in the area.  相似文献   
90.
An ichnofauna consisting of four types of trackways and five types of traces, largely made by arthropods, was discovered in the ?Late Silurian-Early Devonian Mt Daubeny Formation in western New South Wales. The trackways include forms of Diplichnites gouldi, Merostomichnites strandi (most common) and Palmichnium antarticum (form A), and the traces include Cruziana sp. Didymaulichnus lyelli, Didplodichnus biformis, Planolites sp. and Rusophysus sp. The formation, >6 km thick, was deposited during semi-arid and humid climates in a terminal fan environment. The discovery of Palmichnium antarticum (form B) from the Givetian Gum Creek beds at Moona Vale Station is also reported.  相似文献   
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