880 resultados para Two-body correlation
Resumo:
Stable isotope compositions of land snail shells have a great potential as an indicator of paleoclimatic and paleoenvironmental changes. However, some key issues, such as the relationship of carbon isotope between snail food and local vegetation, and the uncertainty of the dominant factors about snail body fluid changes in oxygen isotope composition, remain less well known, strongly limiting shell isotopic application. In this study, we measure the stable isotope compositions on the shells of both live snails and fossils collected from the Chinese Loess Plateau and a loess sequence at Mangshan, Xingyang, respectively. Based on the analyses, the association of the stable isotope compositions of land snail shells with their growing seasons is investigated. In addition, the climatic and environmental significances of isotopic differences among several snail species are discussed. The main results and conclusions are presented as follows: 1. δ18O values for the shell lip samples of Bradybaena ravida redfieldi range from -6.79‰ to -1.92‰, and parallels to the monthly changes of local rain water δ18O, temperature and humidity. The compatibility of shell lip δ18O with monthly modeled shell δ18O indicates that the shell lip δ18O changes are mainly resulted from the 18O variations of rain-water. The shells of a land snail growing in spring could be enriched in 18O, and those growing in summer depleted in 18O. 2. Carbon isotope compositions of snail shells are controlled by their diet, which is affected by the relative proportion of C3 to C4. There are some differences in carbon isotopic compositions among different snail species, especially between P. orphana and V. tenera or P. aeoli. Shell δ13C for P. orphana is the most positive with an average of -5.88 ± 2.54 ‰. The C4 plant fraction of the food for “cold-aridiphilous” taxa, P. aeoli and V. tenera, is distinctly lower than that for “thermo-humidiphilous” taxa, P. orphana, indicating that summer is likely to be the main active season of P. orphana and spring of P. aeoli and V. tenera. Therefore, some discrepancy of carbon isotopic compositions among different species may be related to snail active season. 3. δ13C values among different species have a certain degree of positive correlation, which may be influenced by local vegetation ecosystem. δ13C value of the snail shells (especially P. orphana) shows an eastward increasing trend and consists with the variations of C4 plants biomass in Loess Plateau. The result shows that the carbon isotope in local vegetation ecosystem is one of the main factors influencing δ13C values of snail food. Therefore, both carbon isotopes of local vegetation ecosystem and snail active season contribute to the carbon isotopic differences among different snail species and in different areas. 4. δ13C values of living snail shells and soil organic matter have a positive correlation with each other, which further supports the view that carbon isotope in local vegetation ecosystem is one of the main factors influencing δ13C values of snail food. However, the range of δ13C values of snail food for various species in response to carbon isotope in local vegetation ecosystem is different. It is suggested that 13C enrichment of snail shells relative to local vegetation ecosystem has a potential to indicate snail active season and the degree of climate temperature and humidity. 5. There is a significant negative correlation between carbon and oxygen isotopic compositions of living snail shells in Loess Plateau. This result further supports that snail active season can be inferred based on the shell carbon and oxygen isotopic compositions. Moreover, there are some positive correlations between mean annual temperature and differences of shell δ13C values ( 13CV. tenera-P. orphana) and that of δ18O values ( 18OV. tenera-P. orphana) for P. orphana, a typical “thermo-humidiphilous” taxa, and V. tenera, a typical “cold-aridiphilous” taxa, respectively. It shows that 13CV. tenera-P. orphana and 18OV. tenera-P. orphana may have a potential to indicate mean annual temperature or the length of biological growing season. 6. Stable isotopes of land snail shell in the Mangshan loess sequence show that the shell δ18O value of “cold-aridiphilous” taxa V. tenera is more positive than “thermo-humidiphilous” taxa P. orphana and δ13C value of the former is more negative than the latter. In addition, the shell δ18O value of V. tenera varies significantly in different period. During the last glacial maximum, its δ18O value with an average of -7.89 ‰ is more negative than that (-5.88 ‰) from the last deglaciation to the early Holocene. This phenomenon indicates that its growing season during different period is significantly different. It tends to grow in summer in last glacial maximum. With climate warming, it prefers growing in spring with relatively low temperature. While the shell δ18O value of P. orphana varies in a little range, which shows that its activity season is shorter and mainly in summer. These results further support that the change of the snail growing season is one of the main factors of differences of carbon isotopic compositions among different snail species and varies with time. Furthermore, it is consistent that changes in magnetic susceptibility and trend of differences of shell δ18O values and δ13C values respectively between the two snail fossils. It is further testified that 13CV. tenera-P. orphana and 18OV. tenera-P. orphana may have a potential to indicate mean annual temperature or the length of biological growing season.
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Duobuza copper deposit, newly discovered typical gold-rich porphyry copper deposit with superlarge potential, is located in the Tiegelong Mesozoic tectonic -magmatic arc of the southern edge of Qiangtang block and the northern margin of Bangonghu-Nujiang suture. Quartz diorite porphyrite and grandiorite porphyry, occurred in stock, are the main ore-bearing porphyries. As the emplacement of porphyry stock, a wide range of hydrothermal alteration has developed. Within the framework of the ore district, abundant hydrothermal magnetite developed, and the relationship between precipitation of copper and gold and hydrothermal magnetite seems much close. Correspondingly, a series of veinlets and network veinlets occurred in all alteration zones. Therefore, systematic research on such a superlarge high-grade Duobuza gold-rich porphyry copper deposit can fully revealed the metallogenic characteristics of gold-rich porphyry copper deposits in this region, establish metallogenetic model and prospecting criteria, and has important practical significance on the promotion of regional exploration. In addition, this research on it can enrich metallogenic theory of strong oxidation magma-fluid to gold-rich porphyry copper deposit, and will be helpful to understand the metallogenic characteristics in early of subduction of Gangdese arc stages and its entire evolution history of the Qinghai-Tibet Plateau, the temporal and spatial distribution of ore deposits and their geodynamics settings. Northern ore body of Duobuza copper deposit have been controlled with width (north-south) about 100 ~ 400 m, length (east-west) about 1400 m, dip of 200 °, angle of dip 65 °~ 80 °. And controlled resource amount is of 2.7 million tons Cu with grade 0.94% and 13 tons Au with 0.21g/tAu. Overall features of ore body are large scale, higher grade copper, gold-rich. Ore occurred in the body of granodiotite porphyry and quartz diorite porphyrite and its contact zone with wall rock. Through the detailed mapping and field work studies, some typies of alteration are identificated as follows: albitization, biotititation, sericitization, silication, epidotization, chloritization, carbonatization, illitization, kaolinization and so on. The range of alteration is more than 10km2. Wall alteration zone can be divided into potassic alteration, moderate argillization alteration, argillization, illite-hydromuscovite or propylitization from ore-bearing porphyry center outwards, but phyllic alteration has not well developed and only sericite-quartz veins occurred in local area. Moreover, micro-fracture is development in ore district , and correspondingly a series of veinlets are development as follows: biotite vein (EB type), K-feldspar-biotite-chalcopyrite-quartz vein, magnetite-antinolite-K-feldspar vein, quartz-chalcopyrite-magnetite veins (A-type), quartz-magnetite-biotite-K-feldspar vein, chalcopyrite veinlets in potassic alteration zone; (2) chalcopyrite occurring in the center vein–quartz vein (B type), chalcopyrite veinlets, chalcopyrite-gypsum vein in intermediate argillization alteration; (3) chalcopyrite- pyrite-quartz vein, pyrite-quartz vein, chalcopyrite-gypsum veins, quartz-gypsum- molybdenite-chalcopyrite vein in argillization alteration; (4) gypsum veins, quartz-(molybdenite)-chalcopyrite vein, quartz-pyrite vein, gypsum- chalcopyrite vein, potassium feldspar veinlets, Carbonate veins, quartz-magnetite veins in the wall rock. In short, various veins are very abundant within the framework of the ore district. The results of electronic probe microscopy analysis (EMPA) indicate that Albite (Ab 91.5~99.7%) occurred along the rim of plagioclase phenocryst and fracture, and respresents the earliest stages of alteration. K-feldspar (Or 75.1~96.9%) altered plagioclase phenocryst and matrix or formed secondary potassium feldspar veinlets. Secondary biotite occurred mainly in phenocryst, matrix and veinlets, belong to magnesium-rich biotite formed under the conditions of high-oxidation magma- hydrothermal. Chloritization developed in all alteration zones and alterd iron- magnesium minerals such as biotite and hornblende and then formed chlorite veinlets. As the temperature rises, Si in the tetrahedral site of chlorite decreased, and chlorite component evolved from diabantite to ripiolite. The consistent 280℃~360℃ of formation temperature hinted that chlorite formed on the same temperature range in all alteration zones. However, formation temperature range of chlorite from the gypsum-carbonate-chlorite vein was 190℃~220℃, and it may be the product of the latest stage of hydrothermal activity. The closely relationship between biotite and rutile indicate that most of rutiles are precipitated in the process of biotite alteration and recrystallization. In addition, the V2O3 concentration of rutile from ore body in Duobuza gold-rich porphyry copper deposit is >0.4%, indicate that V concentration in rutile has important significance on marking main ore body of porphyry copper deposit. Apatites from Duobuza deposit all are F-rich. And apatite in the wall rock contained low MnO content and relatively high FeO content, which may due to the basaltic composition of the wall rocks. The MnO in apatite from altered porphyry show a strong positive correlation with FeO. In addition, Cl/F ratio of apatite from wall rock was highest, followed by the potassic alteration zone and potassic alteration zone overprinted by moderate argillization alteration was the lowest. SO2 in Apatite are in the scope of 0 to 0.66%, biotite in the apatite has the highest SO2, followed by the potassic alteration zone, potassic alteration zone overprinted by moderate argillization alteration, and the lowest in the surrounding rocks, which may be caused by the decrease of oxygen fugacity of hydrothermal fluid and S exhaust by sulfide precipitation in potassic alteration. Magnetite in the wall rock have higher Cr2O3 and lower Al2O3 features compared with altered porphyry, this may be due to basalt wall rock generally has high Cr content. And magnetites have higher TiO2 content in potassic alteration than moderate argillization alteration overprinted by potassic alteration, argillization and wall rock, suggested that its formation temperature in potassic alteration was the highest among them. The ore minerals mainly are chalcopyrite and bornite, and Au contents of chalcopyrite, bornite, and pyrite are similar with chalcopyrite slightly higher. The Eu* negative anomaly of disseminated chalcopyrite was relatively lower than chalcopyrite in veinlets. Within a drill hole, the Eu* negative anomaly of disseminated chalcopyrite was gradually larger from bottom to top. Magnetite has the same distribution model, with obvious negative Eu* abnormal, and ΣREE in great changes. The gypsum has the highest ΣREE content and the obvious negative anomaly, and biotite obviously has the Eu* abnormal. Based on the petrographic and geochemical characteristics, five series of magmatic rocks can be broadly classified; they are volcanic rocks of the normal island arc, high-Nb basaltic rocks, adakites, altered porphyry and diorite. The Sr, Nd, Hf isotopes and geochemistry of various series of magmatic rock show that they may be the result of mixing between basic magma and various degrees of acid magma coming from lower crust melted by high temperature basic underplating from partial melting of the subduction sediment melt metasomatic mantle wedge. Furthermore S isotope and Pb isotope of the sulfide, ore-bearing porphyries and volcanic rocks indicated ore-forming source is the mantle wedge metasomatied by subduction sediment melt. Oxygen fugacity of magma estimated by Fe2O3/FeO of whole rock and zircon Ce4+/Ce3+ indicated that the oxidation of basalt-andesitic rocks is higher than ore-forming porphyry, and might imply high-oxidation characteristics of underplated basic magma. Its high oxidative mechanism is likely mantle sources metasomatied by subduction sediment magma, including water and Fe3+. And such high oxidation of basaltic magma is conducive to the mantle of sulfides in the effective access to melt. And the An component of dark part within plagioclase phenocryst zoning belong to bytownite (An 74%), and its may be a result of magma composition changes refreshment by basaltic magma injection. SHRIMP zircon U-Pb and LA-ICP-MS zircon U-Pb geochronology study showed that the intrusions and volcanic rocks from Duobuza porphyry copper deposit belong to early Cretaceous magma series (126~105Ma). The magma evolution series are as follows: the earliest diorite and diorite porphyrite → ore-bearing porphyry and barren grandiorite porphyry →basaltic andesite → diorite porphyrite → andesite → basaltic andesite, and magma component shows a evolution trend from intermediate to intermediate-acid to basic. Based on the field evidences, the formation age of high-Nb basalt may be the latest. The Ar-Ar geochronology of altered secondary biotite, K-feldspar and sericite shows that the main mineralization lasting a interval of about 4 Ma, the duration limit of whole magma-hydrothermal evolution of about 6 Ma, and possibly such a long duration limit may result in the formation of Duobuza super-large copper deposit. Moreover, tectonic diagram and trace element geochemistry of volcanic rocks and diorite from Duobuza porphyry copper deposit confirm that it formed in a continental margin arc environment. Zircon U-Pb age of volcanic rocks and porphyry fall in the range of 105~121Ma, and Duobuza porphyry copper deposit locating in the north of the Bangonghu- Nujiang suture zone, suggested that Neo-Tethys ocean still subducted northward at least early Cretaceous, and its closure time should be later than 105 Ma. Three major inclusion types and ten subtypes are distinguished from quartz phenocrysts and various quartz veins. Vapor generally coexisting with brine inclusions, suggest that fluid boiling may be the main ore-forming mechanism. Raman spectrums of fluid inclusions display that the content of vapor and liquid inclusion mainly contain water, and vapor occasionally contain a little CO2. In addition, the component of liquid inclusions mainly include Cl-, SO42-, Na+, K+, a small amount of Ca2+, F-; and Cl- and Na+ show good correlation. Vapor mainly contains water, a small amount of CO2, CH4 and C2H6 and so on. The daughter minerals identified by Laman spectroscopy and SEM include gypsum, chalcopyrite, halite, sylvite, rutile, potassium feldspar, Fe-Mn-chloride and other minerals, and ore-forming fluid belong to a complex hydrothermal system containing H2O-NaCl-KClFeCl2CaCl2. H and O isotopic analysis of quartz phenocryst, vein quartz, magnetite, chlorite and gypsum from all alteration zones show that the ore-forming fluid of Duobuza gold-rich porphyry copper deposit consisted mainly of magmatic water, without addition of meteric water. Duobuza gold-rich porphyry copper deposit formed by the primary magmatic fluid (600-950C), which has high oxidation, ultra-high salinity and metallogenic element-rich, exsolution direct from the magma, and it is representative of the typical orthomagmatic end member of the porphyry continuum. Moreover, the fluid evolution model of Duobuza gold-rich porphyry copper deposit has been established. Furthermore, two key factors for formation of large Au-rich porphyry copper deposit have been summed up, which are ore-forming fluids earlier separated from magma and high oxidation magma-mineralization fluid system.
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Lower member of the lower Ganchaigou Formation in the southwestern of Qaidam Basin is one of the main targeted exploration zones. With the advancement of exploration, the targets are gradually switching into the lithologic reservoirs and it is urgent to gain the more precise research results in distribution of sedimentary facies and sandstones. Guided by the theory of sequence stratigraphy and sedimentology as well as on the basis of many logging data, drillings, seismic data and chemical tests, the paper comprehensively analyzes the sedimentary facies and sandstones in the lower member of lower Ganchaigou Formation in the southern of Chaixi. According to the identification marks of the key interface in sequence stratigraphy, the key interfaces in lower member of lower Ganchaigou Formation in the southwestern of Qaidam Basin are identified as two third-order sequences SQ1、SQ2. By calibrating the synthetic seismogram, the seismic sequence, well drilling and logging sequences are united. Based on the works above, this paper chooses seven primary cross-sections and builds connecting-well stratigraphic correlation of seven main connecting-well sections. Ultimately, the high-resolution sequence stratigraphic frameworks in the lower member of the lower Ganchaigou Formation, which are uniform to logging and seismic data, are figured out. In terms of study on each sequence features, the main style of the base-level cycle overlay which forms the third-order sequence is confirmed. It contains asymmetric “becoming deep upward” style and symmetry style. Researching on the spreading characters of sequence stratigraphy indicates that SQ1 and SQ2 are rather thicker near northwest well Shashen 20 and Shaxin1 while they are quite thiner near Hongcan 1, Yuejin, Qie 4 and Dong8-Wu3, and the thickness of SQ1 is thicker than SQ2.Based on the deep analysis of the marks for depositional facies, it is proposed that the lake facies and braid river deltas facies mainly occurred in study areas. Besides, the sorts of sub-facies and micro-facies model are divided and described. Under the control of high-resolution sequence stratigraphic framework, three source directions from Arlarer Mountain、Qimantage Mountain and Dongchai Mountain are identified by using the features of heavy mineral assemblage and paleogeomorphy. In addition, regularities of distribution sedimentary facies in sequence stratigraphic framework are studied in accordance with research thinking of the "point" (single well) "line" (section) "face" (plane). In the stage of lower member in the lower Ganchaigou Formation in the southwestern of Qaidam Basin, it is at the early phrase of evolution of the lake basin with the gradual outspread and the rise of the lake level. Combined with physical analysis of reservoir sands formed in different sedimentary environment, the paper studies the style of favorable sandstone bodies that are underwater distributary channel of braided rive delta front, coarse sand in mouth bar and the sand body in sand flat of shore-shallow lacustrine facies. Finally, this article comprehensively analyzes the distribution relationship between sedimentary facies and favorable sandstone body and proposes the ideas that sequence SQ1 Yuejin area, well east 8-wu3 area, well qie4-qie1 area and well hongcan2 area are distributed areas of favorable sandstone.
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Based on geodynamic analysis of sedimentary basins, combined sedimentology with structural geology and other methods, the author studied the Honghe basin located in Yunnan province of Southwestern China. Sandstone slice grain size analysis, combined with field geology and indoors study indicate that a set of inland alluvial fan diposits, fluvial deposites, delta deposits and some lacustrine sediments are in Honghe basin. Studying on shape of the Honghe basin, sedimentary and structural characteristic and distribution of different kinds of conglomerate and its structural significance, we hold the idea that the formation and evolution of Honghe basin are controlled by the activity of Red River faut. Correlation of lithostratic cross section in Honghe basin and studying on activity of Red River fault indicate that Honghe basin was formed in two stages. It is a complex basin constitutes of the first-stage trans-releasing basin and the second-stage trans-downfaulted basin. Due to the uplift of Qinghai-Xizang plateau and deformation of orogeny, the western Yunnan and adjacent area move to SE direction as a result of Tectonic Escape. Right lateral strike slip occurred along Red River fault, trans-releasing basin formed at the bend part of the fault due to stress relexation. As the block escaping, it moves away from the other block of the Red River fault, the upper block move down obliquely and trans-downfaulted basin formed. Combined the age of phytolite and regional structural events, we think the first-stage transreleasing basin was formed in late Miocene, on the other words, the dextral strike slip of Red River fault may began in late Miocene (10-7Ma). The second-stage trans-downfaulted basin may be formed in early stage of Pliocene (about 4.7Ma). Subsequently, the bilateral faults dipping to the inside of the plateau and thrusting outwards occurred in the marginal region of Qinghai-Xizang plateau during its uplifting as a fan-shaped mountain body, this results in the uplift of the strata to the east of Red River fault and supply large quantity of provenance for the Honghe basin. In last Pliocene (about 3Ma), strong uplift of Qinghai-Xizang plateau leads to massive clastic sediment entered Honghe basin and causes its closure. As a kind of trans-tentional basin, trans-releasing basin is different to pull-apart basin. The author compared the Mosha trans-releasing basin with Jinggu pull-apart basin in SW Yunan, China, and described their character correspondingly. Otherwise, the author combined the predecessors' studding with conclusion of own study, discussed the kinematics of Ailaoshan-Red River belt in Cenozoic, and the relationship between the formation of Honghe basin and uplifting of Qinghai-Xizang plateau.
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This dissertation tries to combine the new theories of high-resolution sequence stratigraphy and reservoir architecture with fine sedimentology to form a integral theory system -"high-resolution sequence sedimentology", which can be applied widely ranging from the early petroleum exploration to the tertiary recovery stage in marine and terrestrial basin. So the west slope area in south of Songliao basin, in which, early-fine exploration have been developed, and Xingnan area of Daqing placantictine in high water-bearing and tertiary recovery stage, are selected as target areas to research and analyze. By applying high-resolution sequence stratigraphy theory as well as analysis of source area-facies, the west slope area has been divided into two source areas and three drainage systems and the following conclusions have been drawn: three high values sandstone areas, two sandstone pinchout zones and one stratigraphic pinchout overlap; the facies between Baicheng-Tongyu drainage system is frist ascertained as large-scale argillaceous filled plain facies; fine-grained braided channel-delta depositional system has been found; plane sedimentary facies and microfacies maps of different-scale sequence have been completed, and then twenty-eight lithologic traps have been detected in the east of Taobao-Zhenlai reverse fault zone; In no exploration area of the west, large-scale stratigraiphic overlap heavy oil reservoirs has first been found, which has become an important prograss. In Xingnan area, in the view of high-resolution sequence stratigraphy, the surface of unconformity (the bottom of SSC13) in P I group has been identified, and the following method and technique have been advanced: the division and correlation methods of short-scale base-level cycle sequence (SSC); the comprehensive research methods of SSC plane microfacies; the division technique of hierarchy and type of flow unit, the origin of large-scale composite sandbody and flow unit; And ,on the basis of these, 103 monosandstone bodies and 87 flow units of the third levels have been identified, and four levels of flow units model of five sandstone-bodies types have been established. Because it is a very difficult task all over the world to research architecture in subsurface monosandstone body, brings forward a series of techniques as follows: technique of researching architecture of thin interbed in subsurface monosandstone body; classification, type and liquid-resisting mechanism of thin interbed; multiple-remember vertical subsequence model of remaining oil in monosadstone body. Models of heterogeneity and architecture of thin interbed in five types of monosandstone body have been established. Applying these techniques, type and distribution of remaining oil in different types of monosandstone bodies have been predicated.
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Turbidity sandstone reservoirs have been an important field of hydrocarbon exploration and development in the basins all over the world, as well as in China. Lithologic pools are composed of turbidity sandstones and other sandstones are frequently found in the Jiyang Depression that is a Mesozoic-Cenozoic non-marine oil-bearing basin. The Dongying Sag lies in the sedimentary center of the basin. The subtle traps with turbidity reservoirs are generally difficult to be predicted and described by using current techniques. The studies on turbidity reservoirs plays thus an important theoretical and theoretical practical role in exploration and development in the Jiyang Depression. The attention is, in this thesis, focused on the petrologic properties and oil accumulating behaviors in lake turbidity sedimentary systems in the middle part of the third section of Shahejie Formation in the Dongying Sag, especially in Dongxin area, which lies on the central uplift of the Sag. The paper has disclosed the origin types of turbidity sandstones, distribution pattern and controlling factors of turbidity sandstones, and set up hydrocarbon accumulation patterns of the middle part of the third section of Shahejie Formation in Dongxin, based on nonmarine high resolution sequence stratigraphy, event sedimentology and new theories of hydrocarbon forming. By studying prediction method and technology of turbidity sandstone reservoirs, using precise geological model developing, new techniques of high resolution seismic inversion constrained by logging, the paper has forecast low permeability turbidity sandstone reservoirs and pointed out advantage exploration aims to progressive exploration and development. The paper has obtained mainly many productions and acknowledges as follows: 1.Turbidity sandstone reservoirs of the third section of Shahejie Formationin Dongying Sag are formed in such specifical geological background as rift and extension of basin. The inherited Dongying delta and transgression make up many turbidity distribution areas by overlaying and joining together. The hydrocarbon migrates from depression area to adjacent turbidity sandstone continuously. Accumulation area which is sufficient in oil is formed. 2.The paper has confirmed distinguishable sign of sequence boundary , established stratigraphic framework of Dongying Sag and realized isotime stratigraphic correlation. Es3 of Dongying delta is divided into eleven stages. Among them, the second period of the lower section in Es3, the sixth period of the middle section in Es3, the third period of the upper section in Es3 correspond to eleven sedimentary isotime surface in seismic profile, namely Es3 is classified into eleven Formations. 3.According to such the features of turbidity sandstone as deep in burial, small in area, strong in subtle property, overlaying and joining together and occurring in groups, management through fault and space variations of restriction quantum are realized and the forecast precision of turbidity sandstone by using precise geological model developing, new techniques of high resolution seismic inversion constrained by logging, based on the analysis of all kinds of interwell seismic inversion techniques. 4.According to the features of low permeable turbidity sandstone reservoirs, new method of log interpretation model is put forward. At the same time, distinguish technology of familiar low resistivity oil layer in the turbidity sandstone reservoirs is studied based on petrophysical laboratory work and "four properties" interrelationship between lithological physical Jogging and bearing hydrocarbon properties. Log interpretation model and reservoir index interpretation model of low resistivity oil layer are set up. So the log interpretation precision is improved. 5.The evolution law and its difference of the turbidity sandstone are embodies as follows: the source of sediments come from the south and east of the study area in the middle period of Es3. East source of sediments is pushed from west to east. However, the south source supply of sediments in the early and middle period of Es3 is in full, especially in Es3. subsequently, the supply is decreased gradually. Turbidity fan moves back toward the south and the size of fan is minished accordingly. The characteristic of turbidity sandstone in Dongying Sag is different in different structural positions. Dongxin in the middle-east of the central lift and Niuzhuang Sag He in Dongying delta front and prodelta deep lake subfacies. Although the turbidity sandstone of the two areas root in the Dongying delta sedimentary system, the sand body has different remarkably characteristic. 6.The sedimentary model of the turbiditys in study area have three types as follows: (1) collapse turbidity fan in respect of delta; (2) fault trench turbidity fan; (3) other types of microturbidity sandstone. Middle fan and outer fan, can be found mainly in sublacustrine fan. Middle fan includes braided channel microfacies, central microfacies and braided interchannel microfacies, which is main prospecting oil-bearing subfacies. The middle section of the third section of Shahejie Formation in study area (for example the central lift) can be divided into middle-lower and upper part. The middle-lower part is characteristic of turbidity fan. The upper part is sedimented mainly by delta-collapse fan. 7.The turbidity reservoirs of the middle part of the third section of Shahejie Formation in study area characterize by low maturity both in component and texture, strong in diagenesis and low in permeability. The reservoir can be classified into four types. Type III is the body of reservoir and comprises two types of H a and HI b. M a belongs to middle porosity - low permeability reservoir and distributes in the central lift. Hlb belongs to low porosity - low permeability and distributes in Haojia region. 8.A11 single sand body of lens turbidity reservoir of the middle part of the third section of Shahejie Formation in study area are surrounded by thick dark source rocks. The oil-water system is complex and behaves that every sandstone is single seal unit. The water body is 1/3-1-5 of the sand body. The edge water is not active. The gas exists in the top of reservoir in the form of mixed gas. For far-range turbidity fan with big scale channel, the area and volume of sand body is large and the gap is big in oil packing degree. There are lots of edge water and bottom water, and the latter increases rapidly during the course of development. 9.By exerting the modern hydrocarbon forming theories, the third section of Shahejie Formation in study area belongs to abnormally pressured fluid compartment. The lithological reservoir of the third section of Shahejie Formation is formed in the compartment. The reservoir-formed dynamic system belongs to lower self-source enclosed type. The result and the practice indicate that the form and accumulation of lithological oil reservoirs are controlled by the temperature and pressure of stratum, microfacies, thickness of sand body, fault and reservoir heterogeneity. 10. Based on studies above, the emphases focus on in south and north part of Dongying structure, west Dongxin region and south part Xinzhen structure in the application of production. The practice proves that the turbidity sandstone reservoirs in Ying 11 block and the fault-lithological reservoirs in Xin 133 block have been obtained significant breakthrough. The next target is still sandstone groups of the third section of Shahejie Formation in the bordering areas of Dongxin region for instance Xin 149 area, He 89 area, Ying 8 area etc.
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Comprehensive two-dimensional gas chromatography (GC x GC) has attracted much attention for the analys is of complex samples. Even with a large peak capacity in GC x GC, peak overlapping is often met. In this paper, a new method was developed to resolve overlapped peaks based on the mass conservation and the exponentially modified Gaussian (EMG) model. Linear relationships between the calculated sigma, tau of primary peaks with the corresponding retention time (t(R)) were obtained, and the correlation coefficients were over 0.99. Based on such relationships, the elution profile of each compound in overlapped peaks could be simulated, even for the peak never separated on the second-dimension. The proposed method has proven to offer more accurate peak area than the general data processing method. (c) 2005 Elsevier B.V. All rights reserved.
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Mottram, S. (2005). Reading the rhetoric of nationhood in two Reformation pamphlets by Richard Morison and Nicholas Bodrugan. Renaissance Studies. 19(4), pp.523-540. RAE2008
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M.A. Thesis / University of Pretoria / Department of Practical Theology / Advised by Prof M Masango
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A novel approach for estimating articulated body posture and motion from monocular video sequences is proposed. Human pose is defined as the instantaneous two dimensional configuration (i.e., the projection onto the image plane) of a single articulated body in terms of the position of a predetermined set of joints. First, statistical segmentation of the human bodies from the background is performed and low-level visual features are found given the segmented body shape. The goal is to be able to map these, generally low level, visual features to body configurations. The system estimates different mappings, each one with a specific cluster in the visual feature space. Given a set of body motion sequences for training, unsupervised clustering is obtained via the Expectation Maximation algorithm. Then, for each of the clusters, a function is estimated to build the mapping between low-level features to 3D pose. Currently this mapping is modeled by a neural network. Given new visual features, a mapping from each cluster is performed to yield a set of possible poses. From this set, the system selects the most likely pose given the learned probability distribution and the visual feature similarity between hypothesis and input. Performance of the proposed approach is characterized using a new set of known body postures, showing promising results.
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The relative importance of long-term popularity and short-term temporal correlation of references for Web cache replacement policies has not been studied thoroughly. This is partially due to the lack of accurate characterization of temporal locality that enables the identification of the relative strengths of these two sources of temporal locality in a reference stream. In [21], we have proposed such a metric and have shown that Web reference streams differ significantly in the prevalence of these two sources of temporal locality. These finding underscore the importance of a Web caching strategy that can adapt in a dynamic fashion to the prevalence of these two sources of temporal locality. In this paper, we propose a novel cache replacement algorithm, GreedyDual*, which is a generalization of GreedyDual-Size. GreedyDual* uses the metrics proposed in [21] to adjust the relative worth of long-term popularity versus short-term temporal correlation of references. Our trace-driven simulation experiments show the superior performance of GreedyDual* when compared to other Web cache replacement policies proposed in the literature.
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A non-linear supervised learning architecture, the Specialized Mapping Architecture (SMA) and its application to articulated body pose reconstruction from single monocular images is described. The architecture is formed by a number of specialized mapping functions, each of them with the purpose of mapping certain portions (connected or not) of the input space, and a feedback matching process. A probabilistic model for the architecture is described along with a mechanism for learning its parameters. The learning problem is approached using a maximum likelihood estimation framework; we present Expectation Maximization (EM) algorithms for two different instances of the likelihood probability. Performance is characterized by estimating human body postures from low level visual features, showing promising results.
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A neural model is described of how the brain may autonomously learn a body-centered representation of 3-D target position by combining information about retinal target position, eye position, and head position in real time. Such a body-centered spatial representation enables accurate movement commands to the limbs to be generated despite changes in the spatial relationships between the eyes, head, body, and limbs through time. The model learns a vector representation--otherwise known as a parcellated distributed representation--of target vergence with respect to the two eyes, and of the horizontal and vertical spherical angles of the target with respect to a cyclopean egocenter. Such a vergence-spherical representation has been reported in the caudal midbrain and medulla of the frog, as well as in psychophysical movement studies in humans. A head-centered vergence-spherical representation of foveated target position can be generated by two stages of opponent processing that combine corollary discharges of outflow movement signals to the two eyes. Sums and differences of opponent signals define angular and vergence coordinates, respectively. The head-centered representation interacts with a binocular visual representation of non-foveated target position to learn a visuomotor representation of both foveated and non-foveated target position that is capable of commanding yoked eye movementes. This head-centered vector representation also interacts with representations of neck movement commands to learn a body-centered estimate of target position that is capable of commanding coordinated arm movements. Learning occurs during head movements made while gaze remains fixed on a foveated target. An initial estimate is stored and a VOR-mediated gating signal prevents the stored estimate from being reset during a gaze-maintaining head movement. As the head moves, new estimates arc compared with the stored estimate to compute difference vectors which act as error signals that drive the learning process, as well as control the on-line merging of multimodal information.
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This thesis is presented in two parts. Data for this research is from the Cork BASELINE (Babies after SCOPE, Evaluating Longitudinal Impact using Neurological and Nutritional Endpoints) Birth Cohort Study (n = 2137). In this prospective birth cohort study, pediatric follow-up with in-person appointments were repeated from the time of birth through to 2, 6 and 12 months, and at 2 years. Body composition was measured by air displacement plethysmography at birth and at 2 months using the PEA POD Infant Body Composition Tracking System. This thesis provides the first extensive report on the study’s 2 year assessment. In part one, the aims were to investigate potential early-life risk factors for childhood overweight and obesity, including rapid growth and body composition in infancy and umbilical cord concentrations of leptin and high molecular weight (HMW) adiponectin. This research is the first to describe rapid growth in early infancy in terms of changes in direct measures of body composition. These are also the first data to examine associations between umbilical cord leptin and HMW adiponectin concentrations and changes in fat and lean mass in early infancy. These data provide additional insight into characterising the growth trajectory in infancy and into the role of perinatal factors in determining infant growth and subsequent overweight/obesity risk. In part two of this thesis, the aims were to quantify vitamin D intake and status at 2 years and to investigate whether 25-hydroxyvitamin D [25(OH)D] concentrations in early pregnancy and in umbilical cord blood are associated with infant growth and body composition. There was a low prevalence of vitamin D deficiency among Irish 2 year olds (n = 742) despite a high prevalence of inadequate intakes and high latitude (51°N). Maternal 25(OH)D concentrations at 15 weeks gestation and cord 25(OH)D concentrations at delivery were not associated with infant growth or adiposity.
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Social and ecological factors are important in shaping sexual dimorphism in Anthropoidea, but there is also a tendency for body-size dimorphism and canine dimorphism to increase with increased body size (Rensch's rule) (Rensch: Evolution Above the Species Level. London: Methuen, 1959.) Most ecologist interpret Rensch's rule to be a consequence of social and ecological selective factors that covary with body size, but recent claims have been advanced that dimorphism is principally a consequence of selection for increased body size alone. Here we assess the effects of body size, body-size dimorphism, and social structure on canine dimorphism among platyrrhine monkeys. Platyrrhine species examined are classified into four behavioral groups reflecting the intensity of intermale competition for access to females or to limiting resources. As canine dimorphism increases, so does the level of intermale competition. Those species with monogamous and polyandrous social structures have the lowest canine dimorphism, while those with dominance rank hierarchies of males have the most canine dimorphism. Species with fission-fusion social structures and transitory intermale breeding-season competition fall between these extremes. Among platyrrhines there is a significant positive correlation between body size and canine dimorphism However, within levels of competition, no significant correlation was found between the two. Also, with increased body size, body-size dimorphism tends to increase, and this correlation holds in some cases within competition levels. In an analysis of covariance, once the level of intermale competition is controlled for, neither molar size nor molar-size dimorphism accounts for a significant part of the variance in canine dimorphism. A similar analysis using body weight as a measure of size and dimorphism yields a less clear-cut picture: body weight contributes significantly to the model when the effects of the other factors are controlled. Finally, in a model using head and body length as a measure of size and dimorphism, all factors and the interactions between them are significant. We conclude that intermale competition among platyrrhine species is the most important factor explaining variations in canine dimorphism. The significant effects of size and size dimorphism in some models may be evidence that natural (as opposed to sexual) selection also plays a role in the evolution of increased canine dimorphism.