Recently, a number of large molybdenum (-copper) deposits have been discovered successively in the Laba area, Shangri-La county, northwestern Yunnan province. The investigation confirmed that there is a superlarge por...Recently, a number of large molybdenum (-copper) deposits have been discovered successively in the Laba area, Shangri-La county, northwestern Yunnan province. The investigation confirmed that there is a superlarge porphyry-skarn hydrothermal vein type molybdenum-polymetallic- metallogenic system with the total prediction reservoir of more than 150 mt molybdenum. The porphyry intrusions contributed to the mineralization closely, the superficial little vein molybdenum (-copper, lead, silver) ore-bodies are usually located in faults and fractures, and the deep porphyry type ore-bodies occurred in the granodiorite porphyries, the skarn type ore-bodies occurred in the contact zone intrused into Triassic limestone or Permian basalts. Laba ore block is a new exploration area with great prospecting potential. In order to reduce the target area and guide the further exploration work, the magnetic method measurement about 3.3 square kilometres was carried out in the ore field. This paper presents an application of analyzing the horizontal and vertical derivative, using Fast Fourier Transform (FFT) filter (FFT high-pass, low-pass, cosine roll-off, suscepbility), calculated spectra frequency energy to predict the depth and intensity of the apparent remanence magnetization of source (Hilbert). The calculated results and magnetic anomalous show that the remanence anomaly is caused by the intrusions into the Triassic limestone and Permian basalts with small anomalies, and the depth of located source is not great. We have identified a number of positions to the three drilled well, the drilled result specify interpretation with very high accuracy. The magnetic method is helpful to identify porphyry mineralization, and judge the shape and depth of the concealed ore-bearing intrusive bodies under the similar geological condition.展开更多
Geogas prospecting is a new method in the search for deep and/or concealed mineral deposits.The probing depth of the method comes to 300-500 m below the surface. The method, based on nuclear aualysis and accumulation ...Geogas prospecting is a new method in the search for deep and/or concealed mineral deposits.The probing depth of the method comes to 300-500 m below the surface. The method, based on nuclear aualysis and accumulation sampling, has matured and become useful method of geogas prospecting, through authors' studies more than 10 years. The study of the mechanism for geogas prospecting has also been progressed. It bas been revealed that the geogas matter is in the form of nano-scale particles of the ores by the observation of scanning electron microscope (SEM). This paper summarizes the feature of the geogas anomaly, and describes its forming mechanism. A new example using geogas prospecting is given.展开更多
The results of recent mineral exploration in the Yuele lead-zinc mining area of Daguan County, northeastern Yunnan province, showed that there are much early Paleozoic strata under thick late Paleozoic strata in north...The results of recent mineral exploration in the Yuele lead-zinc mining area of Daguan County, northeastern Yunnan province, showed that there are much early Paleozoic strata under thick late Paleozoic strata in northeastern Yunnan province, where developed some hidden salt structures (SSs), often with lead-zinc polymetallic mineralization varying degrees along the tension torsional fault (belts) or fracture (joint). The ore-bodies belong to the epigenetic hydrothermal filling vein-type deposit, and the prospecting potential is great. In this area, the superficial mineralization information displayed clear, but the deep mineralization is unknown, so the exploration work is restricted. The audio-megnetotelluric (AMT) surveying is an advantageous method to characterize the size, resistivity and skin depth of the polarizable mineral deposit concealed beneath thick overburden. This paper presents the surveying results using AMT method to evaluate the concealed lead-zinc mineralization in Yuele lead-zinc ore field, Daguancounty, NE Yunnan province, China. After comparing the interpretation result of AMT surveying data with the geological data and the drilling data, it is found that there is some distinct difference in resistivity and polarizable between ore-bodies hosted strata, upper strata and gypsum strata. The results show that AMT method is helpful to identify lead-zinc mineralization under this geological condition.展开更多
This paper demonstrates the channels and methods for location prognosis of concealed ore deposits (bodies) in the deep seated and surrounding districts of productive mines in accordance with their special features. Th...This paper demonstrates the channels and methods for location prognosis of concealed ore deposits (bodies) in the deep seated and surrounding districts of productive mines in accordance with their special features. The system frame map is built, from quick exploration in the field to the rapid building of a model indoors. The main research points of location prognosis are also discussed in the paper, which include: 1) integrating the location with the surrounding geological areas, microscopic with macroscopic; 2) analyzing and synthesizing all geological information of different levels, depths and aspects; 3) laying stress on mineralization series; 4) paying attention to the study of the distribution law of ore bodies; 5) introducing the theory of nonlinear dynamics of ore forming processes to ordinary static prognosis; 6) the necessity of the geophysical me thod in recovering information of concealed ore bodies; 7) the combination of all kinds of geology, geophysics, geochemistry and remote sensing methods.展开更多
With the increase of exploration depth,it is more and more difficult to find Au deposits.Due to the limitation of time and cost,traditional geological exploration methods are becoming increasingly difficult to be effe...With the increase of exploration depth,it is more and more difficult to find Au deposits.Due to the limitation of time and cost,traditional geological exploration methods are becoming increasingly difficult to be effectively applied.Thus,new methods and ideas are urgently needed.This study assessed the feasibility and effectiveness of using hyperspectral technology to prospect for hidden Au deposits.For this purpose,48 plant(Seriphidium terrae-albae)and soil(aeolian gravel desert soil)samples were first collected along a sampling line that traverses an Au mineralization alteration zone(Aketasi mining region in an arid region of China)and were used to obtain soil Au contents by a chemical analysis method and the reflectance spectra of plants obtained with an Analytical Spectral Device(ASD)FieldSpec3 spectrometer.Then,the corresponding relationship between the soil Au content anomaly and concealed Au deposits was investigated.Additionally,the characteristic bands were selected from plant spectra using four different methods,namely,genetic algorithm(GA),stepwise regression analysis(STE),competitive adaptive reweighted sampling(CARS),and correlation coefficient method(CC),and were then input into the partial least squares(PLS)method to construct a model for estimating the soil Au content.Finally,the quantitative relationship between the soil Au content and the 15 different plant transformation spectra was established using the PLS method.The results were compared with those of a model based on the full spectrum.The results obtained in this study indicate that the location of concealed Au deposits can be predicted based on soil geochemical anomaly information,and it is feasible and effective to use the full plant spectrum and PLS method to estimate the Au content in the soil.The cross-validated coefficient of determination(R2)and the ratio of the performance to deviation(RPD)between the predicted value and the measured value reached the maximum of 0.8218 and 2.37,respectively,with a minimum value of 6.56μg/kg for the root-mean-squared error(RMSE)in the full spectrum model.However,in the process of modeling,it is crucial to select the appropriate transformation spectrum as the input parameter for the PLS method.Compared with the GA,STE,and CC methods,CARS was the superior characteristic band screening method based on the accuracy and complexity of the model.When modeling with characteristic bands,the highest accuracy,R2 of 0.8016,RMSE of 7.07μg/kg,and RPD of 2.20 were obtained when 56 characteristic bands were selected from the transformed spectra(1/lnR)'(where it represents the first derivative of the reciprocal of the logarithmic spectrum)of sampled plants using the CARS method and were input into the PLS method to construct an inversion model of the Au content in the soil.Thus,characteristic bands can replace the full spectrum when constructing a model for estimating the soil Au content.Finally,this study proposes a method of using plant spectra to find concealed Au deposits,which may have promising application prospects because of its simplicity and rapidity.展开更多
Under the guide of advanced theories of geosciences, new technology and methods of prospecting, integrating sedimentation, magmatic emplacement, metamorphism and deformation with mineralization by means of intersectio...Under the guide of advanced theories of geosciences, new technology and methods of prospecting, integrating sedimentation, magmatic emplacement, metamorphism and deformation with mineralization by means of intersectional subjects, the author has revealed that the geodynamic setting of formation of uranium deposits of granitic exocontact zone type in eastern Hunan and neighbouring areas has a specia1 stretching strike-slip structure, a special thermal rock series,a special texture and composition of the crust and mantle, elaborated the macroscopic and microscopic features of stretching decollement faults in the Mingyuefeng area, and summed up the metallogenic regularities of typical uranium deposits, factors for a genetic mode1 and the criteria for prospecting by synthetic information, on the basis of which he has made prognosis of concealed and blind uranium deposits.展开更多
文摘Recently, a number of large molybdenum (-copper) deposits have been discovered successively in the Laba area, Shangri-La county, northwestern Yunnan province. The investigation confirmed that there is a superlarge porphyry-skarn hydrothermal vein type molybdenum-polymetallic- metallogenic system with the total prediction reservoir of more than 150 mt molybdenum. The porphyry intrusions contributed to the mineralization closely, the superficial little vein molybdenum (-copper, lead, silver) ore-bodies are usually located in faults and fractures, and the deep porphyry type ore-bodies occurred in the granodiorite porphyries, the skarn type ore-bodies occurred in the contact zone intrused into Triassic limestone or Permian basalts. Laba ore block is a new exploration area with great prospecting potential. In order to reduce the target area and guide the further exploration work, the magnetic method measurement about 3.3 square kilometres was carried out in the ore field. This paper presents an application of analyzing the horizontal and vertical derivative, using Fast Fourier Transform (FFT) filter (FFT high-pass, low-pass, cosine roll-off, suscepbility), calculated spectra frequency energy to predict the depth and intensity of the apparent remanence magnetization of source (Hilbert). The calculated results and magnetic anomalous show that the remanence anomaly is caused by the intrusions into the Triassic limestone and Permian basalts with small anomalies, and the depth of located source is not great. We have identified a number of positions to the three drilled well, the drilled result specify interpretation with very high accuracy. The magnetic method is helpful to identify porphyry mineralization, and judge the shape and depth of the concealed ore-bearing intrusive bodies under the similar geological condition.
文摘Geogas prospecting is a new method in the search for deep and/or concealed mineral deposits.The probing depth of the method comes to 300-500 m below the surface. The method, based on nuclear aualysis and accumulation sampling, has matured and become useful method of geogas prospecting, through authors' studies more than 10 years. The study of the mechanism for geogas prospecting has also been progressed. It bas been revealed that the geogas matter is in the form of nano-scale particles of the ores by the observation of scanning electron microscope (SEM). This paper summarizes the feature of the geogas anomaly, and describes its forming mechanism. A new example using geogas prospecting is given.
文摘The results of recent mineral exploration in the Yuele lead-zinc mining area of Daguan County, northeastern Yunnan province, showed that there are much early Paleozoic strata under thick late Paleozoic strata in northeastern Yunnan province, where developed some hidden salt structures (SSs), often with lead-zinc polymetallic mineralization varying degrees along the tension torsional fault (belts) or fracture (joint). The ore-bodies belong to the epigenetic hydrothermal filling vein-type deposit, and the prospecting potential is great. In this area, the superficial mineralization information displayed clear, but the deep mineralization is unknown, so the exploration work is restricted. The audio-megnetotelluric (AMT) surveying is an advantageous method to characterize the size, resistivity and skin depth of the polarizable mineral deposit concealed beneath thick overburden. This paper presents the surveying results using AMT method to evaluate the concealed lead-zinc mineralization in Yuele lead-zinc ore field, Daguancounty, NE Yunnan province, China. After comparing the interpretation result of AMT surveying data with the geological data and the drilling data, it is found that there is some distinct difference in resistivity and polarizable between ore-bodies hosted strata, upper strata and gypsum strata. The results show that AMT method is helpful to identify lead-zinc mineralization under this geological condition.
文摘This paper demonstrates the channels and methods for location prognosis of concealed ore deposits (bodies) in the deep seated and surrounding districts of productive mines in accordance with their special features. The system frame map is built, from quick exploration in the field to the rapid building of a model indoors. The main research points of location prognosis are also discussed in the paper, which include: 1) integrating the location with the surrounding geological areas, microscopic with macroscopic; 2) analyzing and synthesizing all geological information of different levels, depths and aspects; 3) laying stress on mineralization series; 4) paying attention to the study of the distribution law of ore bodies; 5) introducing the theory of nonlinear dynamics of ore forming processes to ordinary static prognosis; 6) the necessity of the geophysical me thod in recovering information of concealed ore bodies; 7) the combination of all kinds of geology, geophysics, geochemistry and remote sensing methods.
基金This research was funded by the National Natural Science Foundation of China(U1803117)the Young Scholars in Western China,Chinese Academy of Sciences(2020-XBQNXZ-014)+3 种基金the Tianchi Doctoral Plan(Y970000317)the Key Project of Natural Science Foundation of China-Xinjiang Joint Fund(U1803241)the Xinjiang Uygur Autonomous Region Talent Special Plan-Tianshan Outstanding Youth(2019Q033)the Geological Exploration Project of Xinjiang Bureau of Geo-exploration and Minera development(XGMB202143).
文摘With the increase of exploration depth,it is more and more difficult to find Au deposits.Due to the limitation of time and cost,traditional geological exploration methods are becoming increasingly difficult to be effectively applied.Thus,new methods and ideas are urgently needed.This study assessed the feasibility and effectiveness of using hyperspectral technology to prospect for hidden Au deposits.For this purpose,48 plant(Seriphidium terrae-albae)and soil(aeolian gravel desert soil)samples were first collected along a sampling line that traverses an Au mineralization alteration zone(Aketasi mining region in an arid region of China)and were used to obtain soil Au contents by a chemical analysis method and the reflectance spectra of plants obtained with an Analytical Spectral Device(ASD)FieldSpec3 spectrometer.Then,the corresponding relationship between the soil Au content anomaly and concealed Au deposits was investigated.Additionally,the characteristic bands were selected from plant spectra using four different methods,namely,genetic algorithm(GA),stepwise regression analysis(STE),competitive adaptive reweighted sampling(CARS),and correlation coefficient method(CC),and were then input into the partial least squares(PLS)method to construct a model for estimating the soil Au content.Finally,the quantitative relationship between the soil Au content and the 15 different plant transformation spectra was established using the PLS method.The results were compared with those of a model based on the full spectrum.The results obtained in this study indicate that the location of concealed Au deposits can be predicted based on soil geochemical anomaly information,and it is feasible and effective to use the full plant spectrum and PLS method to estimate the Au content in the soil.The cross-validated coefficient of determination(R2)and the ratio of the performance to deviation(RPD)between the predicted value and the measured value reached the maximum of 0.8218 and 2.37,respectively,with a minimum value of 6.56μg/kg for the root-mean-squared error(RMSE)in the full spectrum model.However,in the process of modeling,it is crucial to select the appropriate transformation spectrum as the input parameter for the PLS method.Compared with the GA,STE,and CC methods,CARS was the superior characteristic band screening method based on the accuracy and complexity of the model.When modeling with characteristic bands,the highest accuracy,R2 of 0.8016,RMSE of 7.07μg/kg,and RPD of 2.20 were obtained when 56 characteristic bands were selected from the transformed spectra(1/lnR)'(where it represents the first derivative of the reciprocal of the logarithmic spectrum)of sampled plants using the CARS method and were input into the PLS method to construct an inversion model of the Au content in the soil.Thus,characteristic bands can replace the full spectrum when constructing a model for estimating the soil Au content.Finally,this study proposes a method of using plant spectra to find concealed Au deposits,which may have promising application prospects because of its simplicity and rapidity.
文摘Under the guide of advanced theories of geosciences, new technology and methods of prospecting, integrating sedimentation, magmatic emplacement, metamorphism and deformation with mineralization by means of intersectional subjects, the author has revealed that the geodynamic setting of formation of uranium deposits of granitic exocontact zone type in eastern Hunan and neighbouring areas has a specia1 stretching strike-slip structure, a special thermal rock series,a special texture and composition of the crust and mantle, elaborated the macroscopic and microscopic features of stretching decollement faults in the Mingyuefeng area, and summed up the metallogenic regularities of typical uranium deposits, factors for a genetic mode1 and the criteria for prospecting by synthetic information, on the basis of which he has made prognosis of concealed and blind uranium deposits.
