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针对ANDES油田的抗高温高盐二元复合驱油体系研究 被引量:2
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作者 庄天琳 宋考平 +2 位作者 赵宇 王纪伟 宋丽阳 《油田化学》 CAS CSCD 北大核心 2015年第3期392-395,共4页
ANDES油田属于高温(96℃)、高盐(71.5 g/L)油藏。在此条件下,将耐温耐盐理想的疏水缔合聚合物AP-P5与4种表面活性剂复配,发现0.3%的磺酸盐(MJ2)或大庆石油磺酸盐(DQ)与2500mg/LAP-P5形成的二元体系界面张力可以达到10^(-3)mN/m数量级。... ANDES油田属于高温(96℃)、高盐(71.5 g/L)油藏。在此条件下,将耐温耐盐理想的疏水缔合聚合物AP-P5与4种表面活性剂复配,发现0.3%的磺酸盐(MJ2)或大庆石油磺酸盐(DQ)与2500mg/LAP-P5形成的二元体系界面张力可以达到10^(-3)mN/m数量级。考察了温度、矿化度对这两种二元复合体系黏度的影响。结果表明,两种二元复合体系黏度随着温度、矿化度的增加而降低。在96℃、矿化度为70 g/L的条件下,3000 mg/L AP-P5+0.3%MJ2+稳定剂硫脲二元复合体系的黏度为99.4mPa·s,达到现场要求。并且该二元体系在此条件下放置两个月后,黏度趋于稳定,界面张力波动幅度不大。室内物理模拟驱油实验中,当二元复合体系注入体积为0.65 PV时,采收率增幅最大(24.5%)。前期水驱至含水85%+0.65 PV(3000 mg/L AP-P5+0.3%MJ2)+后期水驱至出口含水98%为最佳驱油方案。 展开更多
关键词 andES油田 高温高盐 二元复合驱 疏水缔合聚合物 表面活性剂
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Early-Middle Paleozoic Andes-type Continental Margin in the Chifeng Area, Inner Mongolia: Framework, Geochronology and Geochemistry and Implications for Tectonic Evolution of the Central Asian Orogenic Belt 被引量:5
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作者 YAN Linjie XU Bei +1 位作者 ZHANG Jiaming WANG Yanyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第1期57-74,共18页
Three tectonic units have been recognized in the Chifeng area, Inner Mongolia, from north to south, including the Qiganmiao accretionary prism, Jiefangyingzi arc belt and Sidaozhangpeng molasse basin, which formed an ... Three tectonic units have been recognized in the Chifeng area, Inner Mongolia, from north to south, including the Qiganmiao accretionary prism, Jiefangyingzi arc belt and Sidaozhangpeng molasse basin, which formed an Andeantype active continent margin during the early to middle Paleozoic. The Qiganmiao accretionary prism is characterized by a mélange that consists of gabbro, two-mica quartz schist and basic volcanic rock blocks and heterogeneously deformed marble matrix. Two zircon U-Pb ages of 446.0±6.3 Ma and 1104±27 Ma have been acquired and been interpreted as the metamorphic and forming ages for the gabbro and two-mica quartz schist, respectively. The prism formed during the early to middle Paleozoic southward subduction of the Paleo Asian Ocean(PAO) and represents a suture between the North China craton(NCC) and Central Asian Orogenic Belt(CAOB). The Jiefangyingzi arc belt consists of pluton complex and volcanic rocks of the Xibiehe and Badangshan Formations, and Geochronology analysis indicates that the development of it can be divided into two stages. The first stage is represented by the Xibiehe Formation volcanic rocks, which belong to the subalkaline series, enriched LREE and LILE and depleted HFSE, with negative Eu anomalies, and plot in the volcanic arc field in discrimination diagrams. These characters indicate that the Xibiehe Formation results from to the continental arc magmatic activity related to the subduction of the PAO during 400–420 Ma. Magmatism of the second stage in 380–390 Ma consists of the Badangshan Formation volcanic rocks. Geochemistry analysis reveals that rhyolite, basaltic andesite and basalt of the Badangshan Formation were developed in continental margin arc setting. Moreover, the basaltic andesite and basalt display positive Sr anomalies, and the basalt have very low Nb/La values, suggesting that fluid is involved in magma evolution and the basalts were contaminated by continental crust. The sequence of Sidaozhangpeng molasse basin is characterized by proximity, coarseness and large thickness, similar to the proximity molasses basin. According to our field investigation, geochronological and geochemical data, combined with previous research in this area, a tectonic evolutionary model for Andes-type active continental margin of the CAOB has been proposed, including a development of the subduction-free PAO before 446 Ma, a subduction of the PAO and arc-related magmatism during 446–380 Ma, and formation of a molasse basin during 380–360 Ma. 展开更多
关键词 Chifeng area andes-type continental margin early-middle PALEOZOIC tectonic evolution Central Asian OROGENIC Belt
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Finite element modelling of the geodynamic processes of the Central Andes subduction zone:A Reference Model 被引量:2
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作者 Chris Salomon 《Geodesy and Geodynamics》 2018年第3期246-251,共6页
This paper presents preliminary results of three-dimensional thermomechanical finite-element models of a parameter study to compute the current temperature and stress distribution in the subduction zone of the central... This paper presents preliminary results of three-dimensional thermomechanical finite-element models of a parameter study to compute the current temperature and stress distribution in the subduction zone of the central Andes (16°S-26°S) up to a depth of 400 km, the bottom of the asthenosphere. For this purpose a simulation running over c. 50,000 years will be realized based on the geometry of a generic subduction zone and an elasto-viscoplastic Drucker-Prager rheology. The kinematic and thermal boundary conditions as well as the rheological parameters represent the current state of the study area. In future works the model will be refined using a systematic study of physical parameters in order to estimate the influence of the main parameters (e.g. viscosity, fault friction, velocity, shear heating) on the results of the reference model presented here. The reference model is kept as simple as possible to be able to estimate the influence of the parameters in future studies in the best possible way, whilst minimizing comnutational time. 展开更多
关键词 ABAQUS andes subduction zone Finite element modelling Thermomechanical models VISCOPLASTICITY
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Cenozoic basin evolution of the Central Patagonian Andes:Evidence from geochronology, stratigraphy, and geochemistry 被引量:1
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作者 A.Encinas A.Folguera +6 位作者 R.Riffo P.Molina L.Fernández Paz V.D.Litvak D.A.Colwyn V.A.Valencia M.Carrasco 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第3期1139-1165,共27页
The Central Patagonian Andes is a particular segment of the Andean Cordillera that has been subjected to the subduction of two spreading ridges during Eocene and Neogene times. In order to understand the Cenozoic geol... The Central Patagonian Andes is a particular segment of the Andean Cordillera that has been subjected to the subduction of two spreading ridges during Eocene and Neogene times. In order to understand the Cenozoic geologic evolution of the Central Patagonian Andes, we carried out geochronologic(U-Pb and^(40)Ar/^(39)Ar), provenance, stratigraphic, sedimentologic, and geochemical studies on the sedimentary and volcanic Cenozoic deposits that crop out in the Meseta Guadal and Chile Chico areas(~47°S). Our data indicate the presence of a nearly complete Cenozoic record, which refutes previous interpretations of a hiatus during the middle Eocene-late Oligocene in the Central Patagonian Andes. Our study suggests that the fluvial strata of the Ligorio Marquez Formation and the flood basalts of the Basaltos Inferiores de la Meseta Chile Chico Formation were deposited in an extensional setting related to the subduction of the Aluk-Farallon spreading ridge during the late Paleocene-Eocene. Geochemical data on volcanic rocks interbedded with fluvial strata of the San Jose Formation suggest that this unit was deposited in an extensional setting during the middle Eocene to late Oligocene. Progressive crustal thinning allowed the transgression of marine waters of Atlantic origin and deposition of the upper Oligocene-lower Miocene Guadal Formation. The fluvial synorogenic strata of the Santa Cruz Formation were deposited as a consequence of an important phase of compressive deformation and Andean uplift during the early-middle Miocene. Finally, alkali flood basalts of the late middle to late Miocene Basaltos Superiores de la Meseta Chile Chico Formation were extruded in the area in response to the suduction of the Chile Ridge under an extensional regime. Our studies indicate that the tectonic evolution of the Central Patagonian Andes is similar to that of the North Patagonian Andes and appears to differ from that of the Southern Patagonian Andes, which is thought to have been the subject of continuous compressive deformation since the late Early Cretaceous. 展开更多
关键词 CENTRAL Patagonian andES U-Pb GEOCHRONOLOGY Ar-Ar GEOCHRONOLOGY GEOCHEMISTRY STRATIGRAPHY SEDIMENTOLOGY
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Bank erosion in an Andean páramo river system: Implications for hydro-development and carbon dynamics in the neotropical Andes 被引量:1
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作者 Derek J.MARTIN Christopher ELY Beverley C.WEMPLE 《Journal of Mountain Science》 SCIE CSCD 2019年第2期243-255,共13页
The páramo of the Northern Andes provide critically important ecosystem services to the Northern Andean region in the form of water provisioning and carbon sequestration, both of which are a result of the pá... The páramo of the Northern Andes provide critically important ecosystem services to the Northern Andean region in the form of water provisioning and carbon sequestration, both of which are a result of the páramo?s organic-rich soils. Little is known, however, about the hydro-geomorphic characteristics of the rivers that drain these ecosystems. With impending plans for widespread hydro-development and increasing implementation of carbon-sequestering compensation for ecosystem services programs in the region it is imperative that we develop a thorough understanding of the hydrogeomorphic role that rivers play in this unique ecosystem. The objective of this study was to quantify bank erosion along an Amazonian headwater stream draining a small, relatively undisturbed páramo catchment to gain a better understanding of the natural erosion regime and the resulting sediment contributions from this unique ecosystem. This study implemented a combination of field, laboratory, and Geographic Information Systems techniques to quantify bank erosion rates and determine a bank erosion sediment yield from the Ningar River, a small páramo catchment(22.7 km^2) located in the eastern Andean cordillera of Ecuador. Results show that bank erosion rates range from 3.0 to ≥ 390.0 mm/yr, are highly episodic, and yield at least 487 tons of sediment annually to the Ningar River. These results imply that 1) páramo ecosystems substantially contribute to the sediment load of the Amazon River basin; 2) bank erosion is a potentially significant flux component of basin-scale carbon cycles in páramo ecosystems; and 3) hydrologic alteration campaigns(dam building) will likely critically alter these contributions and concomitantly disconnect a critical source of sediment and nutrients to downstream ecosystems. 展开更多
关键词 BANK EROSION Páramo FLUVIAL GEOMORPHOLOGY andES
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An Andean tectonic cycle:From crustal thickening to extension in a thin crust(34°-37°SL) 被引量:2
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作者 Victor A.Ramos Vanesa D.Litvak +1 位作者 Andrés Folguera Mauro Spagnuolo 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第3期351-367,共17页
Several orogenic cycles of mountain building and subsequent collapse associated with periods of shal- lowing and steepening of subduction zones have been recognized in recent years in the Andes. Most of them are chara... Several orogenic cycles of mountain building and subsequent collapse associated with periods of shal- lowing and steepening of subduction zones have been recognized in recent years in the Andes. Most of them are characterized by widespread crustal delamination expressed by large calderas and rhyolitic flare-up produced by the injection of hot asthenosphere in the subduction wedge. These processes are related to the increase of the subduction angle during trench roll-back. The Payenia paleoflat-slab, in the southern Central Andes of Argentina and Chile (34° -37°S) recorded a complete cycle from crustal thickening and mountain uplift to extensional collapse and normal faulting, which are related to changes in the subduction geometry. The early stages are associated with magmatic expansion and migration, subsequent deformation and broken foreland. New ages and geochemical data show the middle to late Miocene expansion and migration of arc volcanism towards the foreland region was associated with important deformation in the Andean foothills. However, the main difference of this orogenic cycle with the previously described cycles is that the steepening of the oceanic subducted slab is linked to basaltic flooding of large areas in the retroarc under an extensional setting. Crustal delamination is concentrated only in a narrow central belt along the cordilleran axis. The striking differences between the two types of cycles are interpreted to be related to the crustal thickness when steepening the subducting slab, The crustal thickness of the Altiplano is over 60-80 km, whereas Payenia is less than 42 km in the axial part, and near 30 km in the retroarc foothills. The final extensional regime associated with the slab steepening favors the basaltic flooding of more than 8400 km3 in an area larger than 40,000 km2, through 800 central vents and large fissures. These characteristics are unique in the entire present-day Andes. 展开更多
关键词 andes Retroarc magmatism Basaltic floods Crustal delamination Flat-slab
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Phylogeny and evolution of Perezia(Asteraceae:Mutisieae:Nassauviinae)
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作者 Beryl B.SIMPSON Mary T.K.ARROYO +2 位作者 Sandra SIPE Marta DIAS de MORAES Joshua McDILL 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期431-443,共13页
A molecular phylogenetic analysis of most of the species of Perezia reveals that, as traditionally defined, the genus is not monophyletic with two species more closely related to Nassauvia than to Perezia. In addition... A molecular phylogenetic analysis of most of the species of Perezia reveals that, as traditionally defined, the genus is not monophyletic with two species more closely related to Nassauvia than to Perezia. In addition, our results show that Burkartia (Perezia) lanigera is related to Acourtia and is the only member of that clade in South America. The remaining species are monophyletic and show a pattern of an early split between a western temperate and an eastern subtropical clade of species. Within the western clade, the phylogeny indicates a pattern of diversification that proceeded from southern, comparatively low-elevation habitats to southern high-elevation habitats, and ultimately into more northern high-elevation habitats. The most derived clades are found in the high central Andes, where significant radiation has occurred. 展开更多
关键词 andES BIOGEOGRAPHY MUTISIEAE Nassauviinae Perezia.
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Petrogenesis of Quebrada de la Mina and Altar North porphyries (Cordillera of San Juan, Argentina): Crustal assimilation and metallogenic implications
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作者 Laura Maydagán Marta Franchini +4 位作者 Massimo Chiaradia Verónica Bouhier Noelia Di Giuseppe Roger Rey Luis Dimieri 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第5期1135-1159,共25页
We investigate the geology of Altar North(Cu-Au) and Quebrada de la Mina(Au) porphyry deposits located in San Juan Province(Argentina), close to the large Altar porphyry copper deposit(995 Mt,0.35% Cu, 0.083 g/t Au), ... We investigate the geology of Altar North(Cu-Au) and Quebrada de la Mina(Au) porphyry deposits located in San Juan Province(Argentina), close to the large Altar porphyry copper deposit(995 Mt,0.35% Cu, 0.083 g/t Au), to present constraints on the magmatic processes that occurred in the parental magma chambers of these magmatic-hydrothermal systems. Altar North deposit comprises a plagioclase-amphibole-phyric dacite intrusion(Altar North barren porphyry) and a plagioclaseamphibole-biotite-phyric dacite stock(Altar North mineralized porphyry, 11.98 ± 0.19 Ma). In Quebrada de la Mina, a plagioclase-amphibole-biotite-quartz-phyric dacite stock(QDM porphyry,11.91±0.33 Ma) crops out. High Sr/Y ratios(92-142) and amphibole compositions of Altar North barren and QDM porphyries reflect high magmatic oxidation states(fO_2= NNO+1.1 to+1.6) and high fH_2O conditions in their magmas. Zones and rims enriched in anorthite(An_(37-48))), SrO(0.22-0.33 wt.%)and FeO(0.21-0.37 wt.%) in plagioclase phenocrysts are evidences of magmatic recharge processes in the magma chambers. Altar North and Quebrada de la Mina intrusions have relatively homogeneous isotopic compositions(^(87)Sr/^(86)Sr_(t)= 0.70450-0.70466, ε_(ND)(t) = +0.2 to +1.2) consistent with mixed mantle and crust contributions in their magmas. Higher Pb isotopes ratios(^(207)Pb/^(204)Pb=15.6276-15.6294) of these intrusions compared to other porphyries of the district, reflect an increase in the assimilation of high radiogenic Pb components in the magmas. Ages of zircon xenocrysts(297,210,204,69 Ma) revealed that the magmas have experienced assimilation of Miocene, Cretaceous, Triassic and Carboniferous crustal rocks.Fluids that precipitated sulfides in the Altar deposit may have remobilized Pb from the host rocks, as indicated by the ore minerals being more radiogenic(207Pb/204 Pb = 15.6243-15.6269) than their host intrusions. Au/Cu ratio in Altar porphyries(average Au/Cu ratio of 0.14 ×10^(-4)by weight in Altar Central)is higher than in the giant Miocene porphyry deposits located to the south: Los Pelambres, Rio Blanco and Los Bronces(Chile) and Pachon(Argentina). We suggest that the increase in Au content in the porphyries of this region could be linked to the assimilation of high radiogenic Pb components in the magmas within these long-lived maturation systems. 展开更多
关键词 Porphyry High SULFIDATION EPITHERMAL Magmatic recharge Radiogenic isotopes Crustal assimilation Argentinian andES
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Glacier retreat, rock weathering and the growth of lichensin the Churup Valley, Peruvian Tropical Andes
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作者 Adam EMMER Anna JURICOVA Bijeesh Kozhikkodan VEETTIL 《Journal of Mountain Science》 SCIE CSCD 2019年第7期1485-1499,共15页
The most heavily glacierized tropical range in the world– the Peruvian Cordillera Blanca-has been losing ice since the end of the Little Ice Age(LIA).In this study,the decline of the Churup glacier(9°28’18"... The most heavily glacierized tropical range in the world– the Peruvian Cordillera Blanca-has been losing ice since the end of the Little Ice Age(LIA).In this study,the decline of the Churup glacier(9°28’18"S;77°25’02"W)and associated processes were documented employing multi-proxy approach including the analysis of remotely sensed images(1948-2016),the Schmidt hammer rock test and lichenometric dating.It is shown that Churup glacier has lost the vast majority of its estimated LIA extent(1.05±0.1 km^2;45.0×10^6-57.4×10^6 m^3).The rate of glacier retreat is documented to vary in space(SE,SW and NW-facing slopes)and time,with the peak between 1986 and 1995.With an area of 0.045 km^2 in 2016,it is expected that the complete deglaciation of the Churup valley is inevitable in the near future.Recently(post-LIA)exposed bedrock surfaces have shown higher R-values(54.2-66.4,AVG 63.3,STDEV 2.9)compared to pre-LIA exposed surfaces(46.1-59.3,AVG 50.1,STDEV 4.9),confirming the links to the duration of rock weathering.The Lichenometric dating is applied to recently exposed areas and elevations above 4800 m a.s.l.,revealing only limited reliability and agreement with the age of deglaciation estimated from remotely-sensed images in such an environment. 展开更多
关键词 CORDILLERA Blanca Tropical glaciers DEGLACIATION Geoenvironmental change Lichenometry Rhizocarpon geographicum SCHMIDT HAMMER andES
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Effects of Conservation Tillage on Total and Aggregated Soil Organic Carbon in the Andes
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作者 Marcela Quintero Nicholas B. Comerford 《Open Journal of Soil Science》 2013年第8期361-373,共13页
Many Andisols of the Andes have been disturbed by traditional potato-based rotation agriculture disrupting soil structure, water retention capacity and organic matter content. This study was undertaken to investigate ... Many Andisols of the Andes have been disturbed by traditional potato-based rotation agriculture disrupting soil structure, water retention capacity and organic matter content. This study was undertaken to investigate the contribution of conservation farming technology or reduced tillage in potato-based rotations in the Colombian Andes in order to rehabilitate total and aggregated soil organic C in disturbed organic matter-rich Andisols. Soils were sampled from farms with 7-year of reduced tillage and farms with conventional farming practices. Ultrasound energy was applied to samples to disrupt aggregation and total soil C was determined in order to investigate the amount of carbon held inside the aggregates of different soil size classes. Results indicated that reduced tillage in potato-based crop rotations increased the soil C concentration and average C content in the whole profile (≈117 cm depth) by 50 and 33% (1636 t C ha?1 vs. 1224 t C ha?1), respectively, as compared to conventional farming practices. Carbon content increased 177% in the subsoil (A2 horizon, 78 -117 cm depth, from 215 to 596 t?ha?1), although most of the soil C was in the A1 horizon (between 0 -78 cm average thickness, 1097 t?ha?1). These increases show that reduced tillage enhances C stores in Andisols which are already high in organic matter. In addition, C in aggregates represented more than 80% of the total organic matter and it was positively affected by conservation practices. The C increase was preferential in the smaller macroaggregates ( 展开更多
关键词 Conservation TILLAGE SOIL Organic Carbon SOIL AGGREGATES andES POTATO
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Phylogeny and putative hybridization in the subtribe Paranepheliinae (Liabeae, Asteraceae), implications for classification, biogeography, and Andean orogeny
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作者 Akiko SOEJIMA Jun WEN +1 位作者 Mario ZAPATA Michael O. DILLON 《植物分类学报》 CSCD 北大核心 2008年第3期375-390,共16页
The nuclear ribosomal ITS region and the chloroplast trnL-trnF (trnLF) intergenic region were se-quenced for 45 accessions of Paranephelius and six accessions of Pseudonoseris, the two genera of the subtribe Paranephe... The nuclear ribosomal ITS region and the chloroplast trnL-trnF (trnLF) intergenic region were se-quenced for 45 accessions of Paranephelius and six accessions of Pseudonoseris, the two genera of the subtribe Paranepheliinae (Liabeae, Asteraceae) distributed in the alpine regions of the Andes. This data set was used to estimate relationships between these genera and within each genus to aid in evaluating morphological variation and classification. Our results with both ITS and trnLF markers support the monophyly of subtribe Paranephelii-nae, and place Pseudonoseris discolor as the first diverged taxon sister to the clade containing Paranephelius. Pseudonoseris szyszylowiczii exhibited intraspecific divergence supporting intergeneric hybridization between Pseudonoseris and Paranephelius. Within Paranephelius, genetic divergence is low and not adequate to fully resolve phylogenetic relationships at the species level, but two genetically and morphologically recognizable groups were revealed by the ITS data. Several accessions possessing multiple ITS sequences represent putative hybrids between the two groups. These putative hybrids have caused some taxonomic confusion and difficulties in establishing species boundaries in Paranephelius. The divergence time estimates based on ITS sequences indi-cated that the stem of subtribe Paranepheliinae dates to 13 million years ago, but the diversification of the crown clade of the extant members began in the early Pleistocene or late Pliocene, perhaps associated with the uplift of the Andes and the climatic changes of global cooling. 展开更多
关键词 系统演化 杂交 生物地理学 安第斯山脉 造山运动
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New Precipitation and Temperature Grids for Northern Patagonia: Advances in Relation to Global Climate Grids
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作者 Emilio Bianchi Ricardo Villalba +2 位作者 Maximiliano Viale Fleur Couvreux Rocio Marticorena 《Journal of Meteorological Research》 SCIE CSCD 2016年第1期38-52,共15页
Climate data of mean monthly temperature and total monthly precipitation compiled from different sources in northern Patagonia were interpolated to 20-km resolution grids over the period 1997-2010. This northern Patag... Climate data of mean monthly temperature and total monthly precipitation compiled from different sources in northern Patagonia were interpolated to 20-km resolution grids over the period 1997-2010. This northern Patagonian climate grid (NPCG) improves upon previous gridded products in terms of its spatial resolution and number of contributing stations, since it incorporates 218 and 114 precipitation and temper- ature records, respectively. A geostatistical method using surface elevation from a Digital Elevation Model (DEM) as the ancillary variable was used to interpolate station data into even spaced points. The maps provided by NPCG are consistent with the broad spatial and temporal patterns of the northern Patagonian climate, showing a comprehensive representation of the latitudinal and altitudinal gradients in temperature and precipitation, as well as their related patterns of seasonality and continentality. We compared the per- formance of NPCG and various other datasets available to the climate community for northern Patagonia. The grids used for the comparison included those of the Global Precipitation Climatology Project, ERA- Interim, Climate Research Unit (University of East Anglia), and University of Delaware. Based on three statistics that quantitatively assess the spatial coherence of gridded data against available observations (bias, MAE, and RMSE), NPCG outperforms other global grids. NPCG represents a useful tool for understand- ing climate variability in northern Patagonia and a valuable input for regional models of hydrological and ecological processes. Its resolution is optimal for validating data from the general circulation models and working with raster data derived from remote sensing, such as vegetation indices. 展开更多
关键词 northern Patagonia PRECIPITATION temperature CO-KRIGING climate grids Cordillera de los andes
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明代哈密“哈剌灰”及其与裕固族关系考辨
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作者 杨富学 海霞 《内蒙古社会科学》 CSSCI 北大核心 2024年第3期77-83,F0002,共8页
关于明代文献所见哈密“哈剌灰”之名与义,学界多有争议。揆诸《华夷译语·委兀儿译语·地名》中有“黑羊群—噶剌塊”之谓,可以推定“哈剌灰”这一称谓应出自维吾尔语qaraqoi,意为“黑羊群”。作为蒙古豳王家族的属部,元明时... 关于明代文献所见哈密“哈剌灰”之名与义,学界多有争议。揆诸《华夷译语·委兀儿译语·地名》中有“黑羊群—噶剌塊”之谓,可以推定“哈剌灰”这一称谓应出自维吾尔语qaraqoi,意为“黑羊群”。作为蒙古豳王家族的属部,元明时期哈剌灰一直与信仰伊斯兰教的回回和信仰佛教的畏兀儿共处哈密,经历了由伊斯兰教改宗佛教的过程。“哈剌灰”指的就是1276年以后由中亚迁居哈密原本信仰伊斯兰教后皈依佛教的蒙古人。他们在皈依藏传佛教后,仍葆有浓重的伊斯兰文化情结。明正德年间,东迁河西走廊,后融合于裕固族之中。 展开更多
关键词 哈剌灰 蒙古豳王 安定王 宗教信仰
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20个玉米品种在安定区的适应性研究及营养价值评价 被引量:1
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作者 杨文静 赵聖明 +2 位作者 王霞 樊霞 蓝志斌 《饲料研究》 CAS 北大核心 2024年第8期143-149,共7页
试验于2021年-2022年对20个玉米品种的生产性能和饲用品质进行综合评价,旨在筛选出适宜安定区或同类地区种植的青贮玉米品种。2021年对20个参试玉米品种的株高、茎粗、叶片数、单株重、果穗长、果穗粗和穗行数等农艺性状和饲草产量进行... 试验于2021年-2022年对20个玉米品种的生产性能和饲用品质进行综合评价,旨在筛选出适宜安定区或同类地区种植的青贮玉米品种。2021年对20个参试玉米品种的株高、茎粗、叶片数、单株重、果穗长、果穗粗和穗行数等农艺性状和饲草产量进行测定,利用隶属函数法对其营养成分进行综合分析,并结合饲草相对饲喂价值(RFV)和饲草分级指数(GI),对参试品种进行综合评价,初步筛选出兴贮88、先玉1321、中农大2118、京科青贮516、京科968、京九青贮16、同康1号、京科青贮932和先玉1225共9个综合指标较好的品种,于2022年进行第二次试验。2022年采用同样的方法对选出的9个参试品种进一步综合评价,结果表明:京科青贮932、京科青贮516、京九青贮16和兴贮88的适应性好,农艺性状和产量优异,相对饲用价值较高,适宜在安定区或者同类地区推广种植。 展开更多
关键词 玉米品种 安定区 适应性研究 营养价值评价
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高性能材料和耐久性设计在大跨度斜拉桥中的应用与实践
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作者 林全富 《交通节能与环保》 2024年第4期234-238,共5页
高性能材料和工艺的应用,是一种理念创新,也是一种技术创新。本文采用实证分析法,论述了高性能耐久材料在大跨度斜拉桥中的应用细节与实施效果,得到如下结论:高性能混凝土的应用可以极大地提高材料使用效率,减小断面尺寸和结构自重,简... 高性能材料和工艺的应用,是一种理念创新,也是一种技术创新。本文采用实证分析法,论述了高性能耐久材料在大跨度斜拉桥中的应用细节与实施效果,得到如下结论:高性能混凝土的应用可以极大地提高材料使用效率,减小断面尺寸和结构自重,简化结构配筋,简化施工流程,适合各类结构形式与安装方法,特别是在钢-混组合结构中,其优点更加突出;采用高强度钢结构可以有效降低构件的自身重量,降低施工难度;综合长效防腐体系的斜拉索有效满足了桥梁的耐久性和抗风动力性能需求,有效兼顾了运营期构件更换的便利性,对交通限制时间更短、影响更小;新型高性能桥墩防船撞消能装置的正撞碰撞力消减幅度达38.0%。 展开更多
关键词 高性能材料 耐久性设计 大跨度斜拉桥 全生命周期 提质降碳
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2023年甘肃省安定区牛羊布鲁氏菌病的流行病学调查
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作者 张玲萍 马永国 +1 位作者 田华 王振华 《养殖与饲料》 2024年第7期69-72,共4页
[目的]明确甘肃安定区牛羊布鲁氏菌病的感染状况及流行趋势,分析疫情发生的原因和传播途径,为制定针对性的防控措施提供科学依据。[方法]从安定区牛羊规模化养殖场和散养户中随机抽取未进行布病免疫接种的牛羊,2023年1-12月共采集21 01... [目的]明确甘肃安定区牛羊布鲁氏菌病的感染状况及流行趋势,分析疫情发生的原因和传播途径,为制定针对性的防控措施提供科学依据。[方法]从安定区牛羊规模化养殖场和散养户中随机抽取未进行布病免疫接种的牛羊,2023年1-12月共采集21 010份血清样本,其中羊血清样本为13 284份,牛血清样本为7 726份。对安定区牛羊布鲁氏菌病流行病学进行分析,结合实验室检测,确诊疑似病例。[结果]在不同的养殖场地中,种畜场阳性检出率最低,其中种羊场总阳性检出率为0.11%,种牛场总阳性检出率为0。在1年监测周期内,羊布病在3、9、10月的阳性检出率较高,分别为0.37%、0.36%、0.27%;牛布病在4、8、9月阳性检出率较高,分别为0.28%、0.32%、0.31%。[结论]在春秋季节,牛羊布病更容易流行,因此应从监测净化、消毒灭源、养殖管理等方面入手,采取有效的防控措施,减轻牛羊布病的危害。 展开更多
关键词 安定区 牛羊布鲁氏菌病 流行病学调查 布病净化 防控措施
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丹东花岗岩的地球化学特征及其成因 被引量:34
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作者 李三忠 郝德峰 +3 位作者 赵国春 孙敏 韩宗珠 郭晓玉 《岩石学报》 SCIE EI CAS CSCD 北大核心 2004年第6期1417-1423,共7页
新的SHRIMP定年结果表明,原先划归于古元古代的丹东花岗杂岩现在被确定为中生代岩体.其岩浆型环锆石带的年龄代表结晶年龄,为167~157 Ma;但是这些锆石的核部年龄主体为古元古代.本文侧重探讨丹东花岗岩体的岩石学和地球化学特征,论证... 新的SHRIMP定年结果表明,原先划归于古元古代的丹东花岗杂岩现在被确定为中生代岩体.其岩浆型环锆石带的年龄代表结晶年龄,为167~157 Ma;但是这些锆石的核部年龄主体为古元古代.本文侧重探讨丹东花岗岩体的岩石学和地球化学特征,论证其起源和产生的构造背景.研究结果表明,丹东花岗岩体具铕异常(Eu/Eu*=0.59~1.41),轻重稀土分异明显,其微量元素特征与安第斯型构造背景下的花岗岩特征一致,其tDM和εNd(t)变化范围分别为1.93~2.30 Ga和-17.95~-21.32.εNd(t)-t图解显示丹东花岗岩的源岩以古元古代中酸性壳源岩石为主.构造环境环境判别结果表明其形成于大陆边缘岩浆弧.结合中生代丹东地区所处的大地构造背景,本文认为丹东花岗岩体的起源和侵位与古太平洋板块向欧亚板块的俯冲有关. 展开更多
关键词 丹东花岗岩 ND同位素 安第斯型 辽东半岛 中生代
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鄂尔多斯盆地直罗组—安定组沉积期原始边界恢复 被引量:39
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作者 赵俊峰 刘池洋 +4 位作者 梁积伟 王晓梅 喻林 黄雷 刘永涛 《地质学报》 EI CAS CSCD 北大核心 2010年第4期553-569,共17页
有关中生代鄂尔多斯盆地各时期原始沉积面貌的探讨,长期以来深受关注但认识和研究程度不一,其中对于直罗组—安定组沉积期的研究尤为薄弱。本文针对鄂尔多斯克拉通内大型坳陷型盆地的属性及其演化-改造特点,从今盆地及邻区残存沉积建造... 有关中生代鄂尔多斯盆地各时期原始沉积面貌的探讨,长期以来深受关注但认识和研究程度不一,其中对于直罗组—安定组沉积期的研究尤为薄弱。本文针对鄂尔多斯克拉通内大型坳陷型盆地的属性及其演化-改造特点,从今盆地及邻区残存沉积建造、现今构造格局两方面出发,在大量野外露头观测、钻井与测井资料分析及实验测试基础上,通过系统的地层划分与对比、沉积相分析、物源综合分析和对周邻构造单元形成演化史的分析,认为直罗组—安定组沉积期盆地的原始沉积边界大致为:东在今太行山脉以西;北在今河套盆地一带;西北部边界在狼山—巴彦浩特盆地—科学山一带;西南部边界在今六盘山西缘;南部边界在今渭河盆地一带。自盆地周缘向湖盆中心有大致7个方向的物源供给,沉积中心位于原始盆地中心偏南。该期盆地的演化记录了华北克拉通西部由印支期的南北分异向燕山期东西分异的转变过程与时限。该研究对于构建完整的中生代鄂尔多斯盆地演化时空坐标和铀矿、石油等能源矿产勘探评价具有理论和实际意义。 展开更多
关键词 鄂尔多斯盆地 直罗组 安定组 原始沉积边界
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世界盐湖卤水型锂矿特征、分布规律与成矿动力模型 被引量:38
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作者 刘成林 余小灿 +5 位作者 袁学银 李瑞琴 姚佛军 沈立建 李强 赵元艺 《地质学报》 EI CAS CSCD 北大核心 2021年第7期2009-2029,共21页
卤水锂矿在世界探明的锂矿总资源量中占比达65%,由于其易于开采,成本较低,其锂盐产品占总锂盐产品的75%左右。世界卤水锂矿主要产于现代盐湖,这些盐湖分布于世界三大高原:中国青藏高原、南美西部安第斯高原和北美西部高原,形成了三大盐... 卤水锂矿在世界探明的锂矿总资源量中占比达65%,由于其易于开采,成本较低,其锂盐产品占总锂盐产品的75%左右。世界卤水锂矿主要产于现代盐湖,这些盐湖分布于世界三大高原:中国青藏高原、南美西部安第斯高原和北美西部高原,形成了三大盐湖卤水锂成矿区。中国青藏高原盐湖主要包括西藏中北部和柴达木盆地盐湖,卤水锂(LiCl)资源量为2330万t;南美西部安第斯高原盐湖,涵盖玻利维亚、智利和阿根廷盐湖,锂(Li_(2)O)资源量为2300万t;北美西部高原盐湖卤水锂矿(Li__(2)O)资源量为550万t。同时,中国华南地区在中生代晚期可能也是高原环境,高原地貌孕育了大量盐湖,并形成了一些富锂卤水矿。这些高原的形成与隆升都起因于板块俯冲及陆陆碰撞:南美安第斯高原和北美西部高原是太平洋板块向美洲板块俯冲-增生造山形成的,中国青藏高原是印度板块向欧亚板块俯冲-陆陆碰撞形成的,而中国华南古高原则可能与古太平洋板块向亚洲大陆俯冲作用有关。板块俯冲及陆陆碰撞作用,一方面形成高原地貌,挡住了来自大洋的水汽,从而导致高原内部降水减少,形成干旱气候,引发强烈蒸发作用;洋壳俯冲至上地幔之后,由于脱水和部分熔融导致其中的氯、钾、锂和溴等挥发分进入岩浆并被带到地壳浅部富集;板块俯冲-碰撞作用形成大量构造盆地,同时,岩浆活动又引起大量温热泉水活动,高温水-岩反应将地壳中大量锂等成矿物质释放出来,汇入盆地并通过蒸发浓缩形成富锂盐湖。上述构造、气候和物源等成矿要素的耦合,最终导致高原盐湖卤水富锂成矿。综合世界卤水锂矿特征与成矿作用,提出盐湖卤水锂成矿动力学模式。 展开更多
关键词 盐湖 卤水锂矿 板块俯冲 青藏高原 安第斯高原 美国西部高原
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鄂尔多斯盆地中侏罗世直罗—安定期沉积构造特征 被引量:23
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作者 赵俊峰 刘池洋 +2 位作者 喻林 梁积伟 黄雷 《石油与天然气地质》 EI CAS CSCD 北大核心 2006年第2期159-166,共8页
中侏罗世直罗—安定期伴随大华北盆地分化瓦解,直罗—安定组除在鄂尔多斯盆地呈整体分布外,在其周邻地区亦有大量零星分布的同期可对比地层。在现今盆地内,直罗组主要为河流相沉积;安定组以干旱气候条件下的河流、湖泊相沉积为主。直罗... 中侏罗世直罗—安定期伴随大华北盆地分化瓦解,直罗—安定组除在鄂尔多斯盆地呈整体分布外,在其周邻地区亦有大量零星分布的同期可对比地层。在现今盆地内,直罗组主要为河流相沉积;安定组以干旱气候条件下的河流、湖泊相沉积为主。直罗—安定组的湖相沉积主要位于盆地东南部的古沉积中心部位,其堆积中心位于盆地西部的乌海—鄂托克前旗—平凉一线,堆积中心与沉积中心偏离。直罗组沉积前古构造格局为南高北低、东高西低。直罗—安定期的古地质面貌呈西北高东南低特点,南、北分异表现甚微。结合周邻同期地层岩性、岩相和现今构造单元形成时限等综合分析,认为直罗—安定期原始盆地的边界大致为:西在贺兰山之西,东达吕梁山之东、太行山以西,北抵大青山,南至秦岭。 展开更多
关键词 沉积相 古地质构造 直罗-安定期 鄂尔多斯盆地
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