With the efficient and intelligent development of computer-based big data processing,applying machine learning methods to the processing and interpretation of logging data in the field of geophysical well logging has ...With the efficient and intelligent development of computer-based big data processing,applying machine learning methods to the processing and interpretation of logging data in the field of geophysical well logging has broad potential for improving production efficiency.Currently,the Jiyuan Oilfield in the Ordos Basin relies mainly on manual reprocessing and interpretation of old well logging data to identify different fluid types in low-contrast reservoirs,guiding subsequent production work.This study uses well logging data from the Chang 1 reservoir,partitioning the dataset based on individual wells for model training and testing.A deep learning model for intelligent reservoir fluid identification was constructed by incorporating the focal loss function.Comparative validations with five other models,including logistic regression(LR),naive Bayes(NB),gradient boosting decision trees(GBDT),random forest(RF),and support vector machine(SVM),show that this model demonstrates superior identification performance and significantly improves the accuracy of identifying oil-bearing fluids.Mutual information analysis reveals the model's differential dependency on various logging parameters for reservoir fluid identification.This model provides important references and a basis for conducting regional studies and revisiting old wells,demonstrating practical value that can be widely applied.展开更多
Many new forms of Boussinesq-type equations have been developed to extend the range of applicability of the classical Boussinesq equations to deeper water in the Study of the surface waves. One approach was used by Nw...Many new forms of Boussinesq-type equations have been developed to extend the range of applicability of the classical Boussinesq equations to deeper water in the Study of the surface waves. One approach was used by Nwogu （1993. J. Wtrw. Port Coastal and Oc. Eng. 119, 618-638） to improve the linear dispersion characteristics of the classical Boussinesq equations by using the velocity at an arbitrary level as the velocity variable in derived equations and obtain a new form of Boussinesq-type equations, in which the dispersion property can be optimized by choosing the velocity variable at an adequate level. In this paper, a set of Boussinesq-type equations describing the motions of the interracial waves propagating alone the interface between two homogeneous incompressible and inviscid fluids of different densities with a free surface and a variable water depth were derived using a method similar to that used by Nwogu （1993. J. Wtrw. Port Coastal and Oc. Eng. 119, 618-638） for surface waves. The equations were expressed in terms of the displacements of free surface and density-interface, and the velocity vectors at arbitrary vertical locations in the upper layer and the lower layer （or depth-averaged velocity vector across each layer） of a two-layer fluid. As expected, the equations derived in the present work include as special cases those obtained by Nwogu （1993, J. Wtrw. Port Coastal and Oc. Eng. 119, 618-638） and Peregrine （1967, J. Fluid Mech. 27, 815-827） for surface waves when the density of the upper fluid is taken as zero.展开更多
In recent times,scientists and engineers have been most attracted to electrically conducted nanofluids due to their numerous applications in various fields of science and engineering.For example,they are used in cance...In recent times,scientists and engineers have been most attracted to electrically conducted nanofluids due to their numerous applications in various fields of science and engineering.For example,they are used in cancer treatment(hyperthermia),magnetic resonance imaging(MRI),drugdelivery,and magnetic refrigeration(MR).Bearing in mind the significance and importance of electrically conducted nanofluids,this article aims to study an electrically conducted water-based nanofluid containing carbon nanotubes(CNTs).CNTs are of two types,single-wall carbon nanotubes(SWCNTs)and multiple-wall carbon nanotubes(MWCNTs).The CNTs(SWCNTs and MWCNTs)have been dispersed in regular water as base fluid to form waterCNTs nanofluid.The Brinkman Type nanofluid model is developed in terms of time-fractional domain.The ramped heating and sinusoidal oscillations conditions have been taken at the boundary.The model has been solved for exact analytical solutions via the fractional Laplace transform method.The exact solutions have been graphically studied to explore the physics of various pertinent flow parameters on velocity and temperature fields.The empirical results reveal that the temperature and velocity fields decreased with increasing values of fractional parameters due to variation in thermal and momentum boundary layers.It is also indicated that the isothermal velocity and temperature are higher than ramped velocity and temperature.展开更多
Interracial waves propagating along the interface between a three-dimensional two-fluid system with a rigid upper boundary and an uneven bottom are considered. There is a light fluid layer overlying a heavier one in t...Interracial waves propagating along the interface between a three-dimensional two-fluid system with a rigid upper boundary and an uneven bottom are considered. There is a light fluid layer overlying a heavier one in the system, and a small density difference exists between the two layers. A set of higher-order Boussinesq-type equations in terms of the depth-averaged velocities accounting for stronger nonlinearity are derived. When the small parameter measuring frequency dispersion keeping up to lower-order and full nonlinearity are considered, the equations include the Choi and Camassa＇s results （1999）. The enhanced equations in terms of the depth-averaged velocities are obtained by applying the enhancement technique introduced by Madsen et al. （1991） and Schaffer and Madsen （1995a）. It is noted that the equations derived from the present study include, as special cases, those obtained by Madsen and Schaffer （1998）. By comparison with the dispersion relation of the linear Stokes waves, we found that the dispersion relation is more improved than Choi and Camassa＇s （1999） results, and the applicable scope of water depth is deeper.展开更多
A novel-type delivery system consisting of a special feeding device and delivery device was developed and applied to a φ600 mm× 1 000 mm twin-roll casting system for producing the steel strip of 2 mm in thicknes...A novel-type delivery system consisting of a special feeding device and delivery device was developed and applied to a φ600 mm× 1 000 mm twin-roll casting system for producing the steel strip of 2 mm in thickness, and the characteristics of fluid flow and temperature field in the casting pool were investigated by mathematical simulation. The results showed that the melt from the novel-type delivery system was distributed to the casting pool along the width direction smoothly and uniformly. At the casting speed of 80 m/min, the difference of minimum residence time （groin） and actual average residence time （tave） among different ports of the delivery device was less than 0.18 s and 0.26 s respectively, and the average amplitude of level fluctuation was 0.3 mm to 0.6 mm on the free surface of casting pool. In addition, the difference of temperature on the free surface of the pool was below 20 K and the difference across the width direction of roll in different pool depths was less than 13 K, which indicates that the uniformity of temperature distribution was obtained in the casting pool to maintain the casting process and the defect-free steel strip can also be obtained.展开更多
The Jinlongshan gold ore belt in southern Shaanxi Province contains a number of Carlin-type gold deposits in the Qinling collisional orogenic belt. Their fluid inclusions are of the Na-Cl- type. From the main metallog...The Jinlongshan gold ore belt in southern Shaanxi Province contains a number of Carlin-type gold deposits in the Qinling collisional orogenic belt. Their fluid inclusions are of the Na-Cl- type. From the main metallogenic stage to later stages, the total quantity of anions and cations, temperature and deoxidation parameter (R) for fluid inclusions all gradually decreased, suggesting the gradual intensification of fluid oxidation, the reduction of metallogenic depth and the input of meteoric water and organic components. The deposits were formed during crustal uplifting and hence had similar tectonic settings to orogenic gold deposits. The CO-2 contents and CO-2/H-2O values of the ore fluid increased from early to late stages, and the wall-rock alteration is represented by decarbonation, which is inconsistent with the characteristics of orogenic gold deposits. It is also discovered that Na, K, SO{2-}-4, Cl- and the total amounts of anions and cations in the inclusions in quartz are higher than those in the coexisting calcite. The H, O and C isotope ratios indicate that the ore fluid was sourced from meteoric water and metamorphic devolatilisation of the sedimentary rocks that host the ores. The high background {δ{}{18}O} and {δ{}{13}C} values of wall rocks resulted in high {δ{}{18}O} and {δ{}{13}C} values of ore fluid and also high {δ{}{18}O} and {δ{}{13}C} values of hydrothermal minerals such as quartz and carbonate. The carbon in ore fluid stemmed largely from the hosting strata. The {δ{}{18}O} and {δ{}{13}C} values of Fe-calcite and the δD values of fluid inclusions are lower than those of calcite and quartz. In terms of the theory of coordination chemistry, all these differences can be ascribed to water-rock interaction in the same fluid system, instead, to the multi-source of ore fluid.展开更多
Analyses of fluid\|inclusion leachates from ore deposits show that Na/Br ratios are within the range of 75-358 and Cl/Br 67-394, respectively, and this variation trend coincides with the seawater evaporation trajector...Analyses of fluid\|inclusion leachates from ore deposits show that Na/Br ratios are within the range of 75-358 and Cl/Br 67-394, respectively, and this variation trend coincides with the seawater evaporation trajectory on the basis of the Na/Br and Cl/Br ratios. The average Cl/Br and Na/Br ratios of mineralizing fluids are 185 and 173 respectively, which are very close to the ratios (120 and 233) of the residual evaporated seawater past the point of halite precipitation. It is suggested that the original mineralizing brine was derived from highly evaporated seawater with a high salinity. However, the inclusion fluids have absolute Na values of \{69.9\}-\{2606.2\} mmol kg\+\{-1\} and Cl values of \{106.7\}-\{1995.5\} mmol kg\+\{-1\}. Most of the values are much less than those of seawater: Na, 485 mmol kg\+\{-1\} and Cl, 566 mmol kg\+\{-1\}, respectively; the salinity measured from fluid inclusions of the deposits ranges from \{2.47 wt%\} to \{15.78 wt%\} NaCl equiv. The mineralizing brine has been diluted. The \{δ\{\}\+\{18\}O\} and δD values of ore\|forming fluids vary from \{-8.21‰\} to \{9.51‰\} and from \{-40.3‰\} to \{-94.3‰\}, respectively. The δD values of meteoric water in this region varied from \{-80‰\} to \{-100‰\} during the Jurassic. This evidenced that the ore\|forming fluids are the mixture of seawater and meteoric water. Highly evaporated seawater was responsible for leaching and extracting Pb, Zn and Fe, and mixed with and diluted by descending meteoric water, which resulted in the formation of ores.展开更多
Einstein’s field equations with variable gravitational and cosmological constants are considered in presence of perfect fluid for locally-rotationally-symmetric (LRS) Bianchi type-V space-time discussion in context o...Einstein’s field equations with variable gravitational and cosmological constants are considered in presence of perfect fluid for locally-rotationally-symmetric (LRS) Bianchi type-V space-time discussion in context of the particle creation. We present new shear free solutions for both absence and presence of particle creation. The solution describes the particle and entropy generation in the anisotropic cosmological models. We observe that time variation of gravitational and cosmological constant is needed for particle creation phenomena. Moreover, we obtained the particle production rate Γ(t) for this model and discussed in detail.展开更多
Fluid inclusions in quartz from the Lannigou and Yata Carlin\|type gold deposits in southwestern Guizhou were analyzed by inductively coupled plasma\|mass spectrometry for their trace elements (Co, Ni, Cu, Pb, Zn, Pt,...Fluid inclusions in quartz from the Lannigou and Yata Carlin\|type gold deposits in southwestern Guizhou were analyzed by inductively coupled plasma\|mass spectrometry for their trace elements (Co, Ni, Cu, Pb, Zn, Pt, etc.). The results show that quartz fluid inclusions entrapped at different ore\|forming stages contain higher Co, Ni, Cu, Pb and Zn. It has been found for the first time that the ore\|forming fluids responsible for the Carlin\|type gold deposits are rich in Pt. From this it can be concluded that basic volcanic rocks seem to be one of the important sources of ore\|forming materials for the Carlin\|type gold deposits.展开更多
The Xiaohongshilazi mineral deposit in Jilin Province,China,is located in the accretion zone in the northern margin of the North China Block. The deposit contains two types of ore bodies: layered Pb-Zn ore bodies in v...The Xiaohongshilazi mineral deposit in Jilin Province,China,is located in the accretion zone in the northern margin of the North China Block. The deposit contains two types of ore bodies: layered Pb-Zn ore bodies in volcanic rock and vein-hosted Pb-Zn ore bodies controlled by fractures. The vein Pb-Zn ore bodies are strictly controlled by tectonic fracture zones trending in S-N direction,which comprise sulfide veins or sulfidebearing quartz veins distributed along faults or structural fissures. The ores mainly appear mesh-vein and vein structures,and also show solid-solution separation and metasomatic textures. The metal minerals are mainly sphalerite,galena,and pyrite,etc. Wall-rock alteration includes mainly sericitization,chloritization,silicification and carbonatization,etc. Microscope observations and Raman spectroscopy analyses indicate that the oreforming fluid of the vein Pb-Zn ore bodies was mainly magmatic water with low temperature,low salinity,and a shallow depth of metallogenesis( ~ 1.5 km). Sulfur and lead isotope analyses indicate that the sulfide source is mainly formation sulfur or biogenic sulfur,which is similar to the sulfur source of hydrothermal deposit( negative( δ^(34) S values),while the main Pb source was the upper crust with some mantle input. This article argues that the vein Pb-Zn ore body of the Xiaohongshilazi deposit is a low-to medium-temperature hydrothermal vein type related to the formation of a shallow magma chamber.展开更多
Kupferschiefer type Cu-Ag deposits occur in the Upper Permian Xuanwei Formation in the Leshan-Muchuan region at the southwestern edge of the Sichuan Basin. Evidences from geology, major element, REE and thermolurnines...Kupferschiefer type Cu-Ag deposits occur in the Upper Permian Xuanwei Formation in the Leshan-Muchuan region at the southwestern edge of the Sichuan Basin. Evidences from geology, major element, REE and thermolurninescence analyses suggest that these Kupferschiefer type CuAg deposits were formed during diagenesis and the ore-forming fluids were derived frorn the underlying basalt. Fluid dynamic analyses show that the ore-forming fluids migrated in a unicellular convection, fluids migrated through the basalt, leaching Cu and Ag frorn basalt and forming orebearing solutions, up the western basement highs, moved laterally along the Xuanwei Formation toward the basin centers, presumably to sink back down into the basalt, completing a convection cycle which was about 15 km long, 300 m high and subhorizontal. Further analysis and calculation suggest that there are good geological, tectonic and fluid-dynamic conditions to form middle-scale Cu and giant Ag Kupferschiefer type deposits, but superlarge deposits are unlikely to be formed in this region.展开更多
One-dimensional nuclear magnetic resonance （1D NMR） logging technology is limited for fluid typing, while two-dimensional nuclear magnetic resonance （2D NMR） logging can provide more parameters including longitudi...One-dimensional nuclear magnetic resonance （1D NMR） logging technology is limited for fluid typing, while two-dimensional nuclear magnetic resonance （2D NMR） logging can provide more parameters including longitudinal relaxation time （71） and transverse relaxation time （T2） relative to fluid types in porous media. Based on the 2D NMR relaxation mechanism in a gradient magnetic field, echo train simulation and 2D NMR inversion are discussed in detail. For 2D NMR inversion, a hybrid inversion method is proposed based on the damping least squares method （LSQR） and an improved truncated singular value decomposition （TSVD） algorithm. A series of spin echoes are first simulated with multiple waiting times （Tws） in a gradient magnetic field for given fluid models and these synthesized echo trains are inverted by the hybrid method. The inversion results are consistent with given models. Moreover, the numerical simulation of various fluid models such as the gas-water, light oil-water, and vicious oil-water models were carried out with different echo spacings （TEs） and Tws by this hybrid method. Finally, the influences of different signal-to-noise ratios （SNRs） on inversion results in various fluid models are studied. The numerical simulations show that the hybrid method and optimized observation parameters are applicable to fluid typing of gas-water and oil-water models.展开更多
A novel intermediate fluid vaporization (IFV) technology for LNG re-gasification process with spiral-wound heat exchanging tubes is proposed. The new IFV project combines the advantage of running the shell and tube he...A novel intermediate fluid vaporization (IFV) technology for LNG re-gasification process with spiral-wound heat exchanging tubes is proposed. The new IFV project combines the advantage of running the shell and tube heat exchangers at high pressure with the advantage of compact space of heat exchangers. Thermal analysis on the two processes of forced convection and vaporization type heat transfer in the spiral wound tubes and vapor condensation /re-boiling type of heat transfer via intermediate fluid in shell side shows the feasibility of this promising technology.展开更多
Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with un...Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with uncertainties, especially in marginal fields. An approach is employed in this study that integrated rock physics and waveform inverse modelling for lithology and fluid-type characterization to appropriately identify potential hydrocarbon saturated zones and their corresponding lithology. Seismic and well-log data were analyzed using Hampson Russel software. The method adopted includes lithofacies and fluid content analysis using rock physics parameters and seismic simultaneous inverse modelling. Rock physics analysis identified 2 broad reservoirs namely: HDZ1 and HDZ2 reservoirs. Results from the inverse modelling showed that low values of acoustic impedance from 19,743 to 20,487 (ft/s)(g/cc) reflect hydrocarbon-bearing reservoirs while medium to high values shows brine and shale respectively, with brine zone ranging from 20,487 to 22,531 (ft/s)(g/cc) and shale above 22,531 (ft/s)(g/cc). Two lithofacies were identified from inversion analysis of Vp/Vs and Mu-Rho, namely: sand and shale with VpVs 1.95 values respectively. Mu-Rho > 12.29 (GPa)(g/cc) and <12.29 (GPa) (g/cc) represent sand and shale respectively. From 3D volume, it was observed that a high accumulation of hydrocarbon was observed to be saturated at the north to the eastern part of the field forming a meandering channel. Sands were mainly distributed around the northeastern to the southwestern part of the field, that tends to be away from Well 029. This was also validated by the volume of rigidity modulus (Mu-Rho) showing high values indicating sands fall within the northeastern part of the field.展开更多
The characteristics of quartz-hosted fluid inclusions in fluvial sediments from five locations in the upstream,midstream,and estuary of the Changjiang River,China,are analyzed.The sources of sediments are discussed co...The characteristics of quartz-hosted fluid inclusions in fluvial sediments from five locations in the upstream,midstream,and estuary of the Changjiang River,China,are analyzed.The sources of sediments are discussed concerning their differences in the shape,size,number,gas percentage and genetic type of quartz-hosted fluid inclusions.From upstream to downstream,the characteristics of quartz-hosted fluid inclusions in sediments are different.The fluid inclusion types in the samples from upstream to estuary are gradually enriched.The sediment influx from the tributaries of the Changjiang River makes new types of quartz-hosted fluid inclusions in the downstream and estuary.In terms of the number and size,most quartz-hosted fluid inclusions are concentrated in the range of 2-4μm in diameters and 10-150 in number per 10^-3 mm^3.The number and size ranges of the fluid inclusions from different positions are also different.The fluid inclusions in the sample collected from the Shigu,upstream of the Changjiang River,are 2-18μm in size,with the number of 2-166 per 10^-3 mm^3.Among the samples collected from Yibin,Yichang and Wuhan,the sizes of fluid inclusions are 2-15,2-10,2-12μm,with the number of 1-270,2-220,and 1^-308 per 10^-3 mm^3,respectively.The proportion of primary fluid inclusions in the sample of the upstream(14%)is higher than that of the midstream(6%-8%)and the estuary(5%),suggesting that different types of source rocks have been input into the river by the tributaries.The characteristics of quartz-hosted fluid inclusions in the fluvial sediments could offer a new perspective for exploration of the source of sediments.展开更多
基金supported by a project of the Shaanxi Youth Science and Technology Star(2021KJXX-87)public welfare geological survey projects of Shaanxi Institute of Geologic Survey(20180301,201918 and 202103)。
文摘With the efficient and intelligent development of computer-based big data processing,applying machine learning methods to the processing and interpretation of logging data in the field of geophysical well logging has broad potential for improving production efficiency.Currently,the Jiyuan Oilfield in the Ordos Basin relies mainly on manual reprocessing and interpretation of old well logging data to identify different fluid types in low-contrast reservoirs,guiding subsequent production work.This study uses well logging data from the Chang 1 reservoir,partitioning the dataset based on individual wells for model training and testing.A deep learning model for intelligent reservoir fluid identification was constructed by incorporating the focal loss function.Comparative validations with five other models,including logistic regression(LR),naive Bayes(NB),gradient boosting decision trees(GBDT),random forest(RF),and support vector machine(SVM),show that this model demonstrates superior identification performance and significantly improves the accuracy of identifying oil-bearing fluids.Mutual information analysis reveals the model's differential dependency on various logging parameters for reservoir fluid identification.This model provides important references and a basis for conducting regional studies and revisiting old wells,demonstrating practical value that can be widely applied.
文摘Many new forms of Boussinesq-type equations have been developed to extend the range of applicability of the classical Boussinesq equations to deeper water in the Study of the surface waves. One approach was used by Nwogu （1993. J. Wtrw. Port Coastal and Oc. Eng. 119, 618-638） to improve the linear dispersion characteristics of the classical Boussinesq equations by using the velocity at an arbitrary level as the velocity variable in derived equations and obtain a new form of Boussinesq-type equations, in which the dispersion property can be optimized by choosing the velocity variable at an adequate level. In this paper, a set of Boussinesq-type equations describing the motions of the interracial waves propagating alone the interface between two homogeneous incompressible and inviscid fluids of different densities with a free surface and a variable water depth were derived using a method similar to that used by Nwogu （1993. J. Wtrw. Port Coastal and Oc. Eng. 119, 618-638） for surface waves. The equations were expressed in terms of the displacements of free surface and density-interface, and the velocity vectors at arbitrary vertical locations in the upper layer and the lower layer （or depth-averaged velocity vector across each layer） of a two-layer fluid. As expected, the equations derived in the present work include as special cases those obtained by Nwogu （1993, J. Wtrw. Port Coastal and Oc. Eng. 119, 618-638） and Peregrine （1967, J. Fluid Mech. 27, 815-827） for surface waves when the density of the upper fluid is taken as zero.
基金fund from King Saud University through Deanship of Scientific Research,Research Group Program.The authors would also like to acknowledge Ministry of Education(MOE)and Research Management Centre-UTM,Universiti Teknologi Malaysia(UTM)for the financial support through vote Nos.5F004,07G70,07G72,07G76,07G77and 08G33 for this research.
文摘In recent times,scientists and engineers have been most attracted to electrically conducted nanofluids due to their numerous applications in various fields of science and engineering.For example,they are used in cancer treatment(hyperthermia),magnetic resonance imaging(MRI),drugdelivery,and magnetic refrigeration(MR).Bearing in mind the significance and importance of electrically conducted nanofluids,this article aims to study an electrically conducted water-based nanofluid containing carbon nanotubes(CNTs).CNTs are of two types,single-wall carbon nanotubes(SWCNTs)and multiple-wall carbon nanotubes(MWCNTs).The CNTs(SWCNTs and MWCNTs)have been dispersed in regular water as base fluid to form waterCNTs nanofluid.The Brinkman Type nanofluid model is developed in terms of time-fractional domain.The ramped heating and sinusoidal oscillations conditions have been taken at the boundary.The model has been solved for exact analytical solutions via the fractional Laplace transform method.The exact solutions have been graphically studied to explore the physics of various pertinent flow parameters on velocity and temperature fields.The empirical results reveal that the temperature and velocity fields decreased with increasing values of fractional parameters due to variation in thermal and momentum boundary layers.It is also indicated that the isothermal velocity and temperature are higher than ramped velocity and temperature.
基金Knowledge Innovation Programs of the Chinese Academy of Sciences under contract Nos KZCX2-YW-201 and KZCX1-YW-12Natural Science Fund supported by the Educational Department of Inner Mongolia under contract Nos NJzy080005,and NJ09011A Grant from Science Fund for Young Scholars of Inner Mongolia University under contract NoND0801
文摘Interracial waves propagating along the interface between a three-dimensional two-fluid system with a rigid upper boundary and an uneven bottom are considered. There is a light fluid layer overlying a heavier one in the system, and a small density difference exists between the two layers. A set of higher-order Boussinesq-type equations in terms of the depth-averaged velocities accounting for stronger nonlinearity are derived. When the small parameter measuring frequency dispersion keeping up to lower-order and full nonlinearity are considered, the equations include the Choi and Camassa＇s results （1999）. The enhanced equations in terms of the depth-averaged velocities are obtained by applying the enhancement technique introduced by Madsen et al. （1991） and Schaffer and Madsen （1995a）. It is noted that the equations derived from the present study include, as special cases, those obtained by Madsen and Schaffer （1998）. By comparison with the dispersion relation of the linear Stokes waves, we found that the dispersion relation is more improved than Choi and Camassa＇s （1999） results, and the applicable scope of water depth is deeper.
基金Item Sponsored by National Natural Science Foundation of China(51174049,51174052,51374057,51374062)
文摘A novel-type delivery system consisting of a special feeding device and delivery device was developed and applied to a φ600 mm× 1 000 mm twin-roll casting system for producing the steel strip of 2 mm in thickness, and the characteristics of fluid flow and temperature field in the casting pool were investigated by mathematical simulation. The results showed that the melt from the novel-type delivery system was distributed to the casting pool along the width direction smoothly and uniformly. At the casting speed of 80 m/min, the difference of minimum residence time （groin） and actual average residence time （tave） among different ports of the delivery device was less than 0.18 s and 0.26 s respectively, and the average amplitude of level fluctuation was 0.3 mm to 0.6 mm on the free surface of casting pool. In addition, the difference of temperature on the free surface of the pool was below 20 K and the difference across the width direction of roll in different pool depths was less than 13 K, which indicates that the uniformity of temperature distribution was obtained in the casting pool to maintain the casting process and the defect-free steel strip can also be obtained.
文摘The Jinlongshan gold ore belt in southern Shaanxi Province contains a number of Carlin-type gold deposits in the Qinling collisional orogenic belt. Their fluid inclusions are of the Na-Cl- type. From the main metallogenic stage to later stages, the total quantity of anions and cations, temperature and deoxidation parameter (R) for fluid inclusions all gradually decreased, suggesting the gradual intensification of fluid oxidation, the reduction of metallogenic depth and the input of meteoric water and organic components. The deposits were formed during crustal uplifting and hence had similar tectonic settings to orogenic gold deposits. The CO-2 contents and CO-2/H-2O values of the ore fluid increased from early to late stages, and the wall-rock alteration is represented by decarbonation, which is inconsistent with the characteristics of orogenic gold deposits. It is also discovered that Na, K, SO{2-}-4, Cl- and the total amounts of anions and cations in the inclusions in quartz are higher than those in the coexisting calcite. The H, O and C isotope ratios indicate that the ore fluid was sourced from meteoric water and metamorphic devolatilisation of the sedimentary rocks that host the ores. The high background {δ{}{18}O} and {δ{}{13}C} values of wall rocks resulted in high {δ{}{18}O} and {δ{}{13}C} values of ore fluid and also high {δ{}{18}O} and {δ{}{13}C} values of hydrothermal minerals such as quartz and carbonate. The carbon in ore fluid stemmed largely from the hosting strata. The {δ{}{18}O} and {δ{}{13}C} values of Fe-calcite and the δD values of fluid inclusions are lower than those of calcite and quartz. In terms of the theory of coordination chemistry, all these differences can be ascribed to water-rock interaction in the same fluid system, instead, to the multi-source of ore fluid.
基金ThisresearchprojectwasfundedbytheNationalNaturalScienceFoundationofChina (No .4 0 1 72 0 39)
文摘Analyses of fluid\|inclusion leachates from ore deposits show that Na/Br ratios are within the range of 75-358 and Cl/Br 67-394, respectively, and this variation trend coincides with the seawater evaporation trajectory on the basis of the Na/Br and Cl/Br ratios. The average Cl/Br and Na/Br ratios of mineralizing fluids are 185 and 173 respectively, which are very close to the ratios (120 and 233) of the residual evaporated seawater past the point of halite precipitation. It is suggested that the original mineralizing brine was derived from highly evaporated seawater with a high salinity. However, the inclusion fluids have absolute Na values of \{69.9\}-\{2606.2\} mmol kg\+\{-1\} and Cl values of \{106.7\}-\{1995.5\} mmol kg\+\{-1\}. Most of the values are much less than those of seawater: Na, 485 mmol kg\+\{-1\} and Cl, 566 mmol kg\+\{-1\}, respectively; the salinity measured from fluid inclusions of the deposits ranges from \{2.47 wt%\} to \{15.78 wt%\} NaCl equiv. The mineralizing brine has been diluted. The \{δ\{\}\+\{18\}O\} and δD values of ore\|forming fluids vary from \{-8.21‰\} to \{9.51‰\} and from \{-40.3‰\} to \{-94.3‰\}, respectively. The δD values of meteoric water in this region varied from \{-80‰\} to \{-100‰\} during the Jurassic. This evidenced that the ore\|forming fluids are the mixture of seawater and meteoric water. Highly evaporated seawater was responsible for leaching and extracting Pb, Zn and Fe, and mixed with and diluted by descending meteoric water, which resulted in the formation of ores.
文摘Einstein’s field equations with variable gravitational and cosmological constants are considered in presence of perfect fluid for locally-rotationally-symmetric (LRS) Bianchi type-V space-time discussion in context of the particle creation. We present new shear free solutions for both absence and presence of particle creation. The solution describes the particle and entropy generation in the anisotropic cosmological models. We observe that time variation of gravitational and cosmological constant is needed for particle creation phenomena. Moreover, we obtained the particle production rate Γ(t) for this model and discussed in detail.
文摘Fluid inclusions in quartz from the Lannigou and Yata Carlin\|type gold deposits in southwestern Guizhou were analyzed by inductively coupled plasma\|mass spectrometry for their trace elements (Co, Ni, Cu, Pb, Zn, Pt, etc.). The results show that quartz fluid inclusions entrapped at different ore\|forming stages contain higher Co, Ni, Cu, Pb and Zn. It has been found for the first time that the ore\|forming fluids responsible for the Carlin\|type gold deposits are rich in Pt. From this it can be concluded that basic volcanic rocks seem to be one of the important sources of ore\|forming materials for the Carlin\|type gold deposits.
基金Supported by Project of Natural Science Foundation of Jilin Province(No.20170101084JC)
文摘The Xiaohongshilazi mineral deposit in Jilin Province,China,is located in the accretion zone in the northern margin of the North China Block. The deposit contains two types of ore bodies: layered Pb-Zn ore bodies in volcanic rock and vein-hosted Pb-Zn ore bodies controlled by fractures. The vein Pb-Zn ore bodies are strictly controlled by tectonic fracture zones trending in S-N direction,which comprise sulfide veins or sulfidebearing quartz veins distributed along faults or structural fissures. The ores mainly appear mesh-vein and vein structures,and also show solid-solution separation and metasomatic textures. The metal minerals are mainly sphalerite,galena,and pyrite,etc. Wall-rock alteration includes mainly sericitization,chloritization,silicification and carbonatization,etc. Microscope observations and Raman spectroscopy analyses indicate that the oreforming fluid of the vein Pb-Zn ore bodies was mainly magmatic water with low temperature,low salinity,and a shallow depth of metallogenesis( ~ 1.5 km). Sulfur and lead isotope analyses indicate that the sulfide source is mainly formation sulfur or biogenic sulfur,which is similar to the sulfur source of hydrothermal deposit( negative( δ^(34) S values),while the main Pb source was the upper crust with some mantle input. This article argues that the vein Pb-Zn ore body of the Xiaohongshilazi deposit is a low-to medium-temperature hydrothermal vein type related to the formation of a shallow magma chamber.
文摘Kupferschiefer type Cu-Ag deposits occur in the Upper Permian Xuanwei Formation in the Leshan-Muchuan region at the southwestern edge of the Sichuan Basin. Evidences from geology, major element, REE and thermolurninescence analyses suggest that these Kupferschiefer type CuAg deposits were formed during diagenesis and the ore-forming fluids were derived frorn the underlying basalt. Fluid dynamic analyses show that the ore-forming fluids migrated in a unicellular convection, fluids migrated through the basalt, leaching Cu and Ag frorn basalt and forming orebearing solutions, up the western basement highs, moved laterally along the Xuanwei Formation toward the basin centers, presumably to sink back down into the basalt, completing a convection cycle which was about 15 km long, 300 m high and subhorizontal. Further analysis and calculation suggest that there are good geological, tectonic and fluid-dynamic conditions to form middle-scale Cu and giant Ag Kupferschiefer type deposits, but superlarge deposits are unlikely to be formed in this region.
基金sponsored by the National Natural Science Foundation of China(41172130)the Fundamental Research Funds for the Central Universities(2-9-2012-48)+1 种基金the National Major Projects(No.2011ZX05014-001)CNPC Innovation Foundation(No.2011D-5006-0305)
文摘One-dimensional nuclear magnetic resonance （1D NMR） logging technology is limited for fluid typing, while two-dimensional nuclear magnetic resonance （2D NMR） logging can provide more parameters including longitudinal relaxation time （71） and transverse relaxation time （T2） relative to fluid types in porous media. Based on the 2D NMR relaxation mechanism in a gradient magnetic field, echo train simulation and 2D NMR inversion are discussed in detail. For 2D NMR inversion, a hybrid inversion method is proposed based on the damping least squares method （LSQR） and an improved truncated singular value decomposition （TSVD） algorithm. A series of spin echoes are first simulated with multiple waiting times （Tws） in a gradient magnetic field for given fluid models and these synthesized echo trains are inverted by the hybrid method. The inversion results are consistent with given models. Moreover, the numerical simulation of various fluid models such as the gas-water, light oil-water, and vicious oil-water models were carried out with different echo spacings （TEs） and Tws by this hybrid method. Finally, the influences of different signal-to-noise ratios （SNRs） on inversion results in various fluid models are studied. The numerical simulations show that the hybrid method and optimized observation parameters are applicable to fluid typing of gas-water and oil-water models.
基金supported by grants from the Fundamental Research Funds for the Central Universities(DUT12JN01)the National Natural Science Foundation of China(51106017)
文摘A novel intermediate fluid vaporization (IFV) technology for LNG re-gasification process with spiral-wound heat exchanging tubes is proposed. The new IFV project combines the advantage of running the shell and tube heat exchangers at high pressure with the advantage of compact space of heat exchangers. Thermal analysis on the two processes of forced convection and vaporization type heat transfer in the spiral wound tubes and vapor condensation /re-boiling type of heat transfer via intermediate fluid in shell side shows the feasibility of this promising technology.
文摘Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with uncertainties, especially in marginal fields. An approach is employed in this study that integrated rock physics and waveform inverse modelling for lithology and fluid-type characterization to appropriately identify potential hydrocarbon saturated zones and their corresponding lithology. Seismic and well-log data were analyzed using Hampson Russel software. The method adopted includes lithofacies and fluid content analysis using rock physics parameters and seismic simultaneous inverse modelling. Rock physics analysis identified 2 broad reservoirs namely: HDZ1 and HDZ2 reservoirs. Results from the inverse modelling showed that low values of acoustic impedance from 19,743 to 20,487 (ft/s)(g/cc) reflect hydrocarbon-bearing reservoirs while medium to high values shows brine and shale respectively, with brine zone ranging from 20,487 to 22,531 (ft/s)(g/cc) and shale above 22,531 (ft/s)(g/cc). Two lithofacies were identified from inversion analysis of Vp/Vs and Mu-Rho, namely: sand and shale with VpVs 1.95 values respectively. Mu-Rho > 12.29 (GPa)(g/cc) and <12.29 (GPa) (g/cc) represent sand and shale respectively. From 3D volume, it was observed that a high accumulation of hydrocarbon was observed to be saturated at the north to the eastern part of the field forming a meandering channel. Sands were mainly distributed around the northeastern to the southwestern part of the field, that tends to be away from Well 029. This was also validated by the volume of rigidity modulus (Mu-Rho) showing high values indicating sands fall within the northeastern part of the field.
基金This study was supported by the National Basic Research Program of China(No.2013CB956504).
文摘The characteristics of quartz-hosted fluid inclusions in fluvial sediments from five locations in the upstream,midstream,and estuary of the Changjiang River,China,are analyzed.The sources of sediments are discussed concerning their differences in the shape,size,number,gas percentage and genetic type of quartz-hosted fluid inclusions.From upstream to downstream,the characteristics of quartz-hosted fluid inclusions in sediments are different.The fluid inclusion types in the samples from upstream to estuary are gradually enriched.The sediment influx from the tributaries of the Changjiang River makes new types of quartz-hosted fluid inclusions in the downstream and estuary.In terms of the number and size,most quartz-hosted fluid inclusions are concentrated in the range of 2-4μm in diameters and 10-150 in number per 10^-3 mm^3.The number and size ranges of the fluid inclusions from different positions are also different.The fluid inclusions in the sample collected from the Shigu,upstream of the Changjiang River,are 2-18μm in size,with the number of 2-166 per 10^-3 mm^3.Among the samples collected from Yibin,Yichang and Wuhan,the sizes of fluid inclusions are 2-15,2-10,2-12μm,with the number of 1-270,2-220,and 1^-308 per 10^-3 mm^3,respectively.The proportion of primary fluid inclusions in the sample of the upstream(14%)is higher than that of the midstream(6%-8%)and the estuary(5%),suggesting that different types of source rocks have been input into the river by the tributaries.The characteristics of quartz-hosted fluid inclusions in the fluvial sediments could offer a new perspective for exploration of the source of sediments.
