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1.
常熟博物馆所藏的一件清乾隆“彩华堂制”款釉里红“八仙过海”纹盆,集青花、釉里红于一身,色彩的深浅浓淡相互补充,和谐统一,堪称乾隆朝官窑中的精品。  相似文献   

2.
The Anticosti Basin is a large Paleozoic basin in eastern Canada where potential source and reservoir rocks have been identified but no economic hydrocarbon reservoirs have been found. Potential source rocks of the Upper Ordovician Macasty Formation overlie carbonates of the Middle Ordovician Mingan Formation, which are underlain by dolostones of the Lower Ordovician Romaine Formation. These carbonates have been subjected to dissolution and dolomitization and are potential hydrocarbon reservoirs. Numerical simulations of fluid‐overpressure development related to sediment compaction and hydrocarbon generation were carried out to investigate whether hydrocarbons generated in the Macasty Formation could migrate downward into the underlying Mingan and Romaine formations. The modeling results indicate that, in the central part of the basin, maximum fluid overpressures developed above the Macasty Formation due to rapid sedimentation. This overpressured core dissipated gradually with time, but the overpressure pattern (i.e. maximum overpressure above source rock) was maintained during the generation of oil and gas. The downward impelling force associated with fluid‐overpressure gradients in the central part of the basin was stronger than the buoyancy force for oil, whereas the buoyancy force for gas and for oil generated in the later stage of the basin is stronger than the overpressure‐related force. Based on these results, it is proposed that oil generated from the Macasty Formation in the central part of the basin first moved downward into the Mingan and Romaine formations, and then migrated laterally up‐dip toward the basin margin, whereas gas throughout the basin and oil generated in the northern part of the basin generally moved upward. Consequently, gas reservoirs are predicted to occur in the upper part of the basin, whereas oil reservoirs are more likely to be found in the strata below the source rocks. Geofluids (2010) 10 , 334–350  相似文献   

3.
The North European Basin hosts mineral deposits like the Kupferschiefer and the Mississippi Valley Type deposits in the Silesian sub‐basin in Poland. The basement to this basin, exposed in the Harz Mts and in the Flechtingen and Calvörde Blocks, contains Mesozoic Pb–Zn vein mineralization and barite–fluorite deposits as well as massive hematite veins in the Rotliegend volcanics. A comparison of the mineralizing models of these deposits with results from a basin‐wide petrographic, fluid inclusion and stable isotope study shows that the genesis of the mineral deposits can be explained by fluid systems that were active during different stages of basin evolution. These comprise syn‐ to post‐magmatic fluids derived from or mobilized in the course of the Rotliegend magmatism, fluids convecting in the Rotliegend units during the extensional basin subsidence in the Permo‐Triassic and originating from progressive devolatilization of the basin sequence and fluids derived from the overlying Zechstein evaporites. Deep‐reaching fault systems developing during the Cretaceous tectonic reactivation enhanced fluid percolation from the surface to the deep sections of the basin sequence. Identification and correlation of these fluids across the basin and in the mineralizations provide the base for a basin‐wide metallogenetic model.  相似文献   

4.
The hypothesis that basinal brines inherited their major ion chemistries and elevated salinities from evaporated paleoseawaters is tested by comparing the compositions of basinal brines in Silurian (Michigan basin, Illinois basin, Appalachian basin in eastern Ohio) and Jurassic/Cretaceous (Central Mississippi Salt Dome basin, Arkansas shelf, and south‐central Texas) host rocks, when the world oceans were ‘CaCl2 seas’, with those from Permian and Pennsylvanian rocks (Palo Duro basin, Central Basin Platform, and Delaware basin, Texas and New Mexico) when the world oceans were ‘MgSO4 seas’. Basinal brines examined are assumed to have originally formed from evaporation of the same seawaters that produced major evaporites. Sulfate, Mg and K levels in basinal brines are below the concentrations expected from evaporation of seawater of any type, which emphasizes the importance of diagenetic mineral–brine interactions in controlling basinal brine chemistry. There are no major differences in SO4, Mg and K concentrations between basinal brines hosted by rocks originally formed during ages when the world oceans were MgSO4 seas versus CaCl2 seas. Basinal brines in Pennsylvanian–Permian rocks are compositionally distinct (relatively high Na and low Ca) from basinal brines in Silurian, Jurassic and Cretaceous host rocks, which may reflect original differences in seawater chemistry. Basinal brines enriched in Ca and depleted in Na relative to evaporated seawater of any type have traditionally been interpreted to form by albitization of plagioclase feldspar. A new explanation for Ca enrichment and Na depletion of basinal brines is the mixing of evaporated CaCl2‐type seawater with more dilute water. Some basinal brines are similar in major ion composition to evaporated seawater of a particular age, for example basinal brines in the Cretaceous Edwards Group carbonates, Texas, where dolomitization is the only reaction required to convert evaporated Mesozoic CaCl2 seawater into Edwards Group brine.  相似文献   

5.
The organization of ceramic production and distribution among the ancient Hohokam of the Phoenix basin, Arizona, has been documented in recent years with much detail. Based on diverse temper and clay compositions, the provenance of individual ceramics is routinely determined with considerable precision. One exception is phyllite-tempered pottery, which was made in one corner of the basin but also across a broad upland zone adjacent to the north. The phyllite-tempered pottery from different production sources cannot be distinguished on the basis of their temper type. As shown with assays with an electron microprobe, however, both the temper and clay fractions are chemically diverse and geographically distinct, allowing many of the phyllite-tempered wares to be sourced. Among the phyllite-tempered ceramics consumed in the Phoenix basin, some are shown to have been made locally, but, surprisingly, large numbers were imported from the northern uplands. Their numbers support the idea that the connection between the Phoenix basin and the northern uplands was a prominent component of the Hohokam regional economy despite the great difference between them in settlement size and density.  相似文献   

6.
Few sites with evidence for fire use are known from the Last Interglacial in Europe. Hearth features are rarely preserved, probably as a result of post-depositional processes. The small postglacial basins (<300?m in diameter) that dominate the sedimentary context of the Eemian record in Europe are high-resolution environmental archives often containing charcoal particles. This case study presents the macroscopic charcoal record of the Neumark-Nord 2 basin, Germany, and the correlation of this record with the distinct find levels of the basin margin that also contain thermally altered archaeological material. Increased charcoal quantities are shown to correspond to phases of hominin presence—a pattern that fits best with recurrent anthropogenic fires within the watershed. This research shows the potential of small basin localities in the reconstruction of local fire histories, where clear archaeological features like hearths are missing.  相似文献   

7.
A basin-by-basin survey of water-borne freight movements in Siberia. The Ob'-Irtysh basin has gained in significance with the development of its oil and gas resources, and further expansion of water transport depends mainly on construction of additional cargo-handling facilities. In the Yenisey basin, the construction of large hydroelectric dams tends to provide an important deep-water route between Lake Baykal and the sea, but no ship locks are being provided in most of the dams. The importance of the Lena basin has been enhanced since 1951 by the construction of the Tayshet-Lena railroad, providing direct access to the upper Lena from the Trans-Siberian main line. Cargo destined for the north coast of Siberia now moves increasingly through the Lena basin instead of over the Northern Sea Route. The Amur River continues to play an important transport role (especially for lumber and coal movements) even though large segments of the stream are paralleled by the railroad.  相似文献   

8.
Debates about sustainability still take insufficient account of the significance of space and time. In this paper, their significance is demonstrated empirically through an account of the complex environmental and socio-economic impacts of dam construction on flood-plain wetlands in the Hadejia-Jama'are river basin in Nigeria. Socio-economic data from a rapid rural appraisal exercise and household questionnaire survey (data on patterns of production in the flood plain and patterns of mobility) are appraised in the context of patterns of environmental change and of inundation (analysis of riparian vegetation and time-series aerial photographs). The paper concludes that sustainable river basin development requires more attention to be paid to the perspectives derived from different scales of analysis. This calls for appropriate institutions allowing communication at the interface between village-level producer and river basin manager.  相似文献   

9.
程军 《历史地理研究》2020,40(4):119-131
1898年清廷颁布《内港行船章程》后,长江内河轮运骤兴,开放轮船行驶的内港日渐增多,截至1929年全流域有超过418处内港开放行轮,内河航运格局为之一变。长江流域开放行轮的内港在空间上集中于下游地区,中游也有较多分布,上游地区则十分稀少。行轮内港的开放在时间上则呈现出下游到上游、干流到支流两种趋势。近代行轮内港的时空变迁趋势反映了轮运这一新式交通在长江流域的发展情况。  相似文献   

10.
Field sampling and mathematical modeling are used to study the long‐distance transport and attenuation of petroleum‐derived benzene in the Uinta Basin, Utah. Benzene concentration was measured from oil and oil field formation waters of the Altamont‐Bluebell and Pariette Bench oil fields in the basin. It was also measured from springs located in the regional groundwater discharge areas, hydraulically down‐gradient from the oil fields sampled. The average benzene concentration in oils and co‐produced waters is 1946 and 4.9 ppm at the Altamont‐Bluebell field and 1533 and 0.6 ppm at the Pariette Bench field, respectively. Benzene concentration is below the detection limit in all springs sampled. Mathematical models are constructed along a north–south trending transect across the basin through both fields. The models represent groundwater flow, heat transfer and advective/dispersive benzene transport in the basin, as well as benzene diffusion within the oil reservoirs. The coupled groundwater flow and heat transfer model is calibrated using available thermal and hydrologic data. We were able to reproduce the observed excess fluid pressure within the lower Green River Formation and the observed convective temperature anomalies across the northern basin. Using the computed best‐fit flow and temperature, the coupled transport model simulates water washing of benzene from the oil reservoirs. Without the effect of benzene attenuation, dissolved benzene reaches the regional groundwater discharge areas in measurable concentration (>0.01 ppm); with attenuation, benzene concentration diminishes to below the detection limit within 1–4 km from the reservoirs. Attenuation also controls the amount of water washing over time. In general, models that represent benzene attenuation in the basin produce results more consistent with field observations.  相似文献   

11.
River basin management activities are often carried out in the context of real or perceived environmental change. Views of environmental change provided by the oral tradition are compared with histories of change reconstructed from the historical documentary record for the Nogoa River, Queensland, and the Avon River, Victoria. Quite different perspectives on the nature and causes of river channel change are provided by the two types of sources. River basin managers appear to have generally adopted the views provided by the more easily accessible oral tradition, leading to management strategies that are not necessarily justifiable in the light of the documentary history.  相似文献   

12.
A critique review of the state of quantitative basin modeling is presented. Over the last 15 years, a number of models are proposed to advance our understanding of basin evolution. However, as of present, most basin models are two dimensional (2‐D) and subject to significant simplifications such as depth‐ or effective stress‐dependent porosity, no stress calculations, isotropic fracture permeability, etc. In this paper, promising areas for future development are identified. The use of extensive data sets to calibrate basin models requires a comprehensive reaction, transport, mechanical (RTM) model in order to generate the synthetic response. An automated approach to integrate comprehensive basin modeling and seismic, well‐log and other type of data is suggested. The approach takes advantage of comprehensive RTM basin modeling to complete an algorithm based on information theory that places basin modeling on a rigorous foundation. Incompleteness in a model can self‐consistently be compensated for by an increase in the amount of observed data used. The method can be used to calibrate the transport, mechanical, or other laws underlying the model. As the procedure is fully automated, the predictions can be continuously updated as new observed data become available. Finally, the procedure makes it possible to augment the model itself as new processes are added in a way that is dictated by the available data. In summary, the automated data/model integration places basin simulation in a novel context of informatics that allows for data to be used to minimize and assess risk in the prediction of reservoir location and characteristics.  相似文献   

13.
Thermally re‐equilibrated fluid inclusions are reported in natural fissure quartz (qtz1) from polymineralic veins in the diagenetic‐anchizonal clastic sedimentary rocks of the Ciñera‐Matallana coal basin (Variscan, NW Spain). Euhedral quartz formed during early fissure opening from an immiscible fluid mixture composed of a low salinity aqueous solution and a CH4‐rich vapour phase, at temperatures of about 110–120°C and pressures ranging from 15 to 56 MPa. Five textural types of re‐equilibration are recognised in progressive order of inclusion modification: scalloped, hairy, annular‐ring shaped, haloes and decrepitation clusters. These textures resulted from a combination of brittle fracturing and dissolution and re‐precipitation of quartz, with preferential loss of water. The thermal peak was short‐lived, but was high enough to induce extensive decrepitation of fluid inclusions in vein quartz throughout the entire basin. Enhanced temperatures can be related to the intrusion of diorites in the basin. Careful analysis of textural features in fluid inclusions from diagenetic and very low‐grade metamorphism environments constitutes a useful tool for recording basin thermal history.  相似文献   

14.
Seven vein types are recognized in three continental Devonian molasse basins (the Hornelen, Kvamshesten and Solund basins) in western Norway. These include calcite‐, quartz‐ and epidote‐dominated veins. The salinities of fluid inclusions from quartz‐dominated veins in the Hornelen and Kvamshesten basins are close to or slightly higher than those for modern seawater, whereas the fluids from quartz‐ and calcite‐dominated veins in the Solund basin range from seawater values to 20 wt % NaCl equivalent. Minerals such as biotite, amphibole, titanite, chlorite and epidote are abundant in the latter veins, and are important constituents of the authigenic mineral assemblages. A combination of fluid inclusion and petrological data suggest that at least some of the veins formed at depths around 12–14 km. The Cl/Br ratios and the salinity of the fluid inclusions can be explained by interactions with evaporites, implying that the sedimentary environment forming the basin fill had the strongest influence upon low‐grade metamorphic fluid Cl and Br contents. Differences in the Cl/I and Na/Br ratios between the Solund basin and the Hornelen and Kvamshesten basins are best explained by local mass transfer between pore fluids and the surrounding rock matrix during burial and increasing temperatures.  相似文献   

15.
Basin‐wide sediment transport affects estimates of basin sediment yield, which is a fundamental scientific issue in drainage basin studies. Many studies have been conducted to examine erosion and deposition rates in drainage networks. In this study, we proposed a new approach using grain‐size standard deviation model of sedimentary samples from different geomorphological units for numerical analysis and paleo‐climate interpretation in the Shiyang River drainage basin, arid China. 1043 sedimentary samples were obtained from the upper reaches, the midstream alluvial plain and the terminal lake area; chronological frames were established based on 58 radiocarbon ages. Grain‐size standard deviation model was introduced to examine sediment components according to grain‐size and transport forces. In addition, transient paleo‐climate simulations, including the Community Climate System Model version 3 and the Kiel models, were synthesized, as well as the results from PMIP 3.0 project, to detect the long‐term climate backgrounds. Totally, we found four major common components, including fine particulates (<2 μm), fine silt (2–20 μm), sandy silt (20–200 μm), coarse sand (>200 μm), from basin‐wide sedimentary samples. The fine particulates and fine silt components exist in all the sedimentary facies, showing long‐term airborne aerosol changes and its transport by suspended load. There are some differences in ranges of sandy silt and coarse sand components, due to lake and river hydrodynamics, as well as the distance with the Gobi Desert. Paleo‐climate simulations have shown that the strong Asian summer monsoon during the transition of the Last Deglaciation and Holocene was conducive to erosion and transport of basin‐wide suspended load, also enhancing sediment sorting effects due to strong lake hydrodynamics. Our findings provide a new approach in research of long‐term basin‐wide sediment transport processes.  相似文献   

16.
This paper outlines the main geomorphological characteristics of the Araguari River Basin and describes the human‐induced changes to the landscapes. This region, naturally occupied by savannas, has been strongly altered by human activities over the previous 40 years. Summarised information is derived from geomorphological, geological and pedological maps, supported by field work. The paper is divided into two main parts. The first shows the natural arrangement of the landscapes in the hydrographic basin, demonstrating the relationships between structural and geomorphic units. Information about superficial materials and current processes and some observations on the evolution of these landforms are presented here. The second part describes the changes in the basin due to anthropic activities, considering types of erosion, channel changes and urban problems. These activities are divided between rural and urban areas, showing the differences between the operations of these sensitive systems. The paper also notes the main research in progress in this basin, presents some partial results and comments on future perspectives.  相似文献   

17.
The sources of high quality volcanic glass (obsidian) for archaeological complexes in the Amur River basin of the Russian Far East have been established, based on geochemical analyses by neutron activation and X-ray fluorescence of both ‘geological’ (primary sources) and ‘archaeological’ (artifacts from the Neolithic and Early Iron Age cultural complexes) specimens. A major obsidian source identified as the Obluchie Plateau, located in the middle course of the Amur River, was found to be responsible for supplying the entire middle and lower parts of the Amur River basin during prehistory. The source has been carefully studied and sampled for the first time. Minor use of three other sources was established for the lower part of the Amur River basin. Obsidian from the Basaltic Plateau source, located in the neighboring Primorye (Maritime) Province, was found at two sites of the Initial Neolithic (dated to ca. 11,000–12,500 BP). At two other sites from the same time period, obsidian from a still unknown source called “Samarga” was established. At the Suchu Island site of the Early Neolithic (dated to ca. 7200–8600 BP), obsidian from the ‘remote’ source of Shirataki (Shirataki-A sub-source) on Hokkaido Island (Japan) was identified. The range of obsidian transport in the Amur River basin was from 50 to 750 km within the basin, and from 550 to 850 km in relation to the ‘remote’ sources at the Basaltic Plateau and Shirataki-A located outside the Amur River valley. The long-distance transport/exchange of obsidian in the Amur River basin in prehistory has now been securely established.  相似文献   

18.
2005年6~7月,南京博物院对新浮遗址进行试掘,发现了灰坑等遗迹,出土陶器、石器以及少量的原始瓷器等遗物。该遗址属于早期湖熟文化,遗物与郑州二里冈遗址下层有很多相似之处,年代相当于中原的商代早期。此次发掘丰富了早期湖熟文化的内涵,反映了早期湖熟文化在茅山山脉以东也有所发展。  相似文献   

19.
The palaeontological data on mammal remains from two Middle Palaeolithic (ca. 125 000 years ago – 27 200 BP) and 34 (ca. 34 000–12 000 BP) Upper Palaeolithic cultural complexes in the upper part of the Yenisei River basin (southern Siberia) are considered. General features of the faunal assemblages are established. Several issues are discussed, including (a) changes in species composition through time and palaeoenvironmental implications of the zooarchaeological records; (b) patterns of human exploitation (hunting) of mammals; (c) issue of mammoth hunting and (d) possibility of domestication of dog in the late Upper Palaeolithic in the Yenisei River basin. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

20.
新石器时代我国辽河流域、黄河流域与长江流域三个地区的玉器,在材质、造型和纹饰方面表现出强烈的区域性特征:辽河流域的玉器多采用岫岩玉为原料,长江流域的玉器则多用透闪石一阳起石制成,而黄河流域多见绿松石制成的器物;辽河流域的玉器纹饰简单风格朴实,长江流域的玉器器形和纹饰都很特别,黄河流域则多生产工具且光素无纹.此外,玉器反映了新石器时代中晚期辽河流域内渔猎经济和宗教在社会中居于主导地位,长江流域中下游地区则可能进入了王权、军权和神权一体化的方国阶段,而世俗权力的独大在黄河流域普遍存在.世俗权力在这一地区社会政治生活中占据了主导地位.  相似文献   

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