2010 Vol. 38 No. 1
2010, 38(1): 1-6.
DOI: 10.3969/j.issn.1001-1986.2010.01.001
Abstract：
In the study of sequence stratigraphy and litho-palaeogeography,quantitative analysis,precise calculation and detailed comparison of tremendous geological data,such as field profiles,logging records and artificial seismic curves from different areas,are the basic requirements.In order to obtain more reliable and precise result,we have developed a method,by combining the spatial database analysis and the single-factor mapping technology,to establish sequence stratigraphical succession and to map the Ordovician litho-paleogeography of the Ordos basin-one of the largest oil-gas bearing basin in North China Platform.By using the method,all of the related basic geological data can be quantitatively analyzed and scientifically managed.Various attributes of the basic stratigraphic units and their characters,such as the overall color,sequence and parasequence thickness,pene-contemporaneous dolostone content,shallow water plaster content,terrigenous material content,carbonate grain ratio,parasequence number,and the relative thickness of the lower and upper units in a parasequence,can be fully utilized statistically in facie analysis and in mapping.Based on this analysis,we have exerted single-factor isopachous mapping quantitatively for each of the Ordovician sequences in the basin,and finally synthezed multiple factors to construct the litho-palaeogeographical maps for each of the sequence intervals.The study shows that the proposed method is quite effective and has much higher resolution in recognizing litho-paleogeographic units than traditional ways.For example,in one of the Middle Ordovician sequence interval(the SQ17 in Lower Majiagou Formaton) of the Ordos basin,we have successfully mapped the precise distribution of various facie units.
In the study of sequence stratigraphy and litho-palaeogeography,quantitative analysis,precise calculation and detailed comparison of tremendous geological data,such as field profiles,logging records and artificial seismic curves from different areas,are the basic requirements.In order to obtain more reliable and precise result,we have developed a method,by combining the spatial database analysis and the single-factor mapping technology,to establish sequence stratigraphical succession and to map the Ordovician litho-paleogeography of the Ordos basin-one of the largest oil-gas bearing basin in North China Platform.By using the method,all of the related basic geological data can be quantitatively analyzed and scientifically managed.Various attributes of the basic stratigraphic units and their characters,such as the overall color,sequence and parasequence thickness,pene-contemporaneous dolostone content,shallow water plaster content,terrigenous material content,carbonate grain ratio,parasequence number,and the relative thickness of the lower and upper units in a parasequence,can be fully utilized statistically in facie analysis and in mapping.Based on this analysis,we have exerted single-factor isopachous mapping quantitatively for each of the Ordovician sequences in the basin,and finally synthezed multiple factors to construct the litho-palaeogeographical maps for each of the sequence intervals.The study shows that the proposed method is quite effective and has much higher resolution in recognizing litho-paleogeographic units than traditional ways.For example,in one of the Middle Ordovician sequence interval(the SQ17 in Lower Majiagou Formaton) of the Ordos basin,we have successfully mapped the precise distribution of various facie units.
2010, 38(1): 7-13.
DOI: 10.3969/j.issn.1001-1986.2010.01.002
Abstract：
In order to discuss the orientation of research on coal and gas outburst mechanism,research findings of coal and gas outburst mechanism were presented in this paper,Different thoughts and methods of research on coal and gas outburst mechanism were expounded,so were the processes of development and current situation of research on coal and gas outburst mechanism.Limitations of existing research findings on coal and gas outburst mechanism were analyzed.Orientation of research on coal and gas outburst mechanism was proposed as well.Currently,research on coal and gas outburst mechanism has developed from single-factor level to multiple-factor level and hypothesis of comprehensive function of multiple-factor has received wide acceptance,which has built theoretical basis for outburst prevention measures in coal mine.Domestic researchers have made abundant achievements in the research on mechanism of coal and gas outburst,which has advanced and developed the mechanism.It was believed that the mechanisms of outburst preparation,outburst instability and balancing,outburst development,outburst transmission of coal and gas,as well as the regularity of distribution of regions where coal and gas outburst tend to take place are the research orientation for deepened study of the mechanism of coal and gas outburst.
In order to discuss the orientation of research on coal and gas outburst mechanism,research findings of coal and gas outburst mechanism were presented in this paper,Different thoughts and methods of research on coal and gas outburst mechanism were expounded,so were the processes of development and current situation of research on coal and gas outburst mechanism.Limitations of existing research findings on coal and gas outburst mechanism were analyzed.Orientation of research on coal and gas outburst mechanism was proposed as well.Currently,research on coal and gas outburst mechanism has developed from single-factor level to multiple-factor level and hypothesis of comprehensive function of multiple-factor has received wide acceptance,which has built theoretical basis for outburst prevention measures in coal mine.Domestic researchers have made abundant achievements in the research on mechanism of coal and gas outburst,which has advanced and developed the mechanism.It was believed that the mechanisms of outburst preparation,outburst instability and balancing,outburst development,outburst transmission of coal and gas,as well as the regularity of distribution of regions where coal and gas outburst tend to take place are the research orientation for deepened study of the mechanism of coal and gas outburst.
2010, 38(1): 14-17.
DOI: 10.3969/j.issn.1001-1986.2010.01.003
Abstract：
On the basis of reorganization statistics and mapping analysis of geological structure data from exploration,mine building and mining,the author has systematically summarized the development features,combination and distribution regularities of geological structures in mined area,and carried out forecast of geological structures in unmined area in Xiangshan coal mine.The results indicated that faults were very developed in coal seams,great number of middle and small scale faults had evident directivity in main mined seam,the extension direction of faults was mainly NW,secondly nearly EW,NE and SN.The development of faults had evident zonation.Geological structures in seam 3 have been divided into 4 structure belt groups and 16 structure belts.In these structure belts,coal seams were complex structurally,which has serious impact on safe mining,while between these belts coal seam was relatively simple in structure.
On the basis of reorganization statistics and mapping analysis of geological structure data from exploration,mine building and mining,the author has systematically summarized the development features,combination and distribution regularities of geological structures in mined area,and carried out forecast of geological structures in unmined area in Xiangshan coal mine.The results indicated that faults were very developed in coal seams,great number of middle and small scale faults had evident directivity in main mined seam,the extension direction of faults was mainly NW,secondly nearly EW,NE and SN.The development of faults had evident zonation.Geological structures in seam 3 have been divided into 4 structure belt groups and 16 structure belts.In these structure belts,coal seams were complex structurally,which has serious impact on safe mining,while between these belts coal seam was relatively simple in structure.
2010, 38(1): 18-21.
DOI: 10.3969/j.issn.1001-1986.2010.01.004
Abstract：
The Late Permian coal-accumulating area in eastern Ynnan and western Guizhou is an important coal-forming area in south China.The paper,based on geological data and practices,disscussed and sumed up the depositional characteristics and coal-forming regularities in tidal flats in the area.The results indicated that specific depositional structures of tidal flat system were abundant in the area,mainly included single clay layer,double clay layer,tidal cyclic sequences,bivariate rhythmic structures of up-tide and down-tide deposits,flat and round mud pebbles,bidirectional mud pebbles,gradational cyclic tidal sequence and mud scour channels,etc.Depositional sequence of tidal flats and planar sand bodies were evident.Sand bodies in tidal channels were generally parpenticular to the shore,and often pinched out towards the land.Wide and stable high quality coal seams were mostly formed in tidal flat environments under relatively stable tectonic conditions.But in areas such as tidal channels,lagoon and gulf flooded by sea water for long time,sulfure content often increased in coal seams.It was pointed out that tidal flat system was one of the important coal-forming environments for stable high quality coal seams in the area.
The Late Permian coal-accumulating area in eastern Ynnan and western Guizhou is an important coal-forming area in south China.The paper,based on geological data and practices,disscussed and sumed up the depositional characteristics and coal-forming regularities in tidal flats in the area.The results indicated that specific depositional structures of tidal flat system were abundant in the area,mainly included single clay layer,double clay layer,tidal cyclic sequences,bivariate rhythmic structures of up-tide and down-tide deposits,flat and round mud pebbles,bidirectional mud pebbles,gradational cyclic tidal sequence and mud scour channels,etc.Depositional sequence of tidal flats and planar sand bodies were evident.Sand bodies in tidal channels were generally parpenticular to the shore,and often pinched out towards the land.Wide and stable high quality coal seams were mostly formed in tidal flat environments under relatively stable tectonic conditions.But in areas such as tidal channels,lagoon and gulf flooded by sea water for long time,sulfure content often increased in coal seams.It was pointed out that tidal flat system was one of the important coal-forming environments for stable high quality coal seams in the area.
2010, 38(1): 22-25.
DOI: 10.3969/j.issn.1001-1986.2010.01.005
Abstract：
Based on the Langmuir equation,Fick unsteady diffusion law and Darcy equation,the partial differential equations and the definite conditions which describe the mechanism of coal gas and water flow were established in consideration of gravity and compression.The method of finite difference was presented to solve the equations.It can be concluded that the model and algorithm are available on predicting the productivity of coalbed methane horizontal well.According to the productivity results under different fissure permeability,we can conclude that the peak time will be artificially shortened and the peak gas rate will be exaggerated,the energy of gas expansion is decreased and the productivity is underestimated if the unsteady diffusion and the compression are ignored.The higher fissure permeability is,the greater the effect of permeability reversion on productivity.The shorter the duration of peak gas rate is,the faster the decline rate will be.In order to reduce the disadvantage of the effect of permeability reversion,a thoughtful bottom hole flowing pressure should be set during production to establish a reasonable pressure system.
Based on the Langmuir equation,Fick unsteady diffusion law and Darcy equation,the partial differential equations and the definite conditions which describe the mechanism of coal gas and water flow were established in consideration of gravity and compression.The method of finite difference was presented to solve the equations.It can be concluded that the model and algorithm are available on predicting the productivity of coalbed methane horizontal well.According to the productivity results under different fissure permeability,we can conclude that the peak time will be artificially shortened and the peak gas rate will be exaggerated,the energy of gas expansion is decreased and the productivity is underestimated if the unsteady diffusion and the compression are ignored.The higher fissure permeability is,the greater the effect of permeability reversion on productivity.The shorter the duration of peak gas rate is,the faster the decline rate will be.In order to reduce the disadvantage of the effect of permeability reversion,a thoughtful bottom hole flowing pressure should be set during production to establish a reasonable pressure system.
2010, 38(1): 26-28,32.
DOI: 10.3969/j.issn.1001-1986.2010.01.006
Abstract：
On the basis of systemic sample collection,by analyzing macerals,micro-fracture,facies,quality and mercury injection test on coal samples,the authors systematically studied the physical characteristics of Jurassic coal bed methane reservoirs in western Ordos basin.And the favorable area was calculated using multi-level fuzzy evaluation method.The results show that the Jurassic coal bed methane(CBM) reservoir in western Ordos basin has great gas potential,and its pore system has bimodal distribution,and is dominated by micropores,mini pores and macropores.The Erdaoling-Rujigou region is considered as the most favorable target area for CBM development.
On the basis of systemic sample collection,by analyzing macerals,micro-fracture,facies,quality and mercury injection test on coal samples,the authors systematically studied the physical characteristics of Jurassic coal bed methane reservoirs in western Ordos basin.And the favorable area was calculated using multi-level fuzzy evaluation method.The results show that the Jurassic coal bed methane(CBM) reservoir in western Ordos basin has great gas potential,and its pore system has bimodal distribution,and is dominated by micropores,mini pores and macropores.The Erdaoling-Rujigou region is considered as the most favorable target area for CBM development.
2010, 38(1): 29-32.
DOI: 10.3969/j.issn.1001-1986.2010.01.007
Abstract：
It is usually required that the gas content determined on coal cores is delivered rapidly in the course of coal and coalbed methane(CBM) exploration.However,the existing method of CBM content determination is hard to meet the requirement.Based on the principle and methodology of CBM natural desorption,on the basis of the result of natural desorption,and under remaining the desorbed volume,gas composition and its content basically unchanged,the gas desorption rate is sped up reasonably and effectively by the use of continuous measuring and appropriately raising desorption temperature.Taking the determination analog between the rapid method and conventional natural desorption as a basis,the method of the rapid CBM content determination is built up.Comparatively,the application of rapid method will shorten the determining period to several days or even several hours,which is able to meet the demand for coal and CBM exploration.
It is usually required that the gas content determined on coal cores is delivered rapidly in the course of coal and coalbed methane(CBM) exploration.However,the existing method of CBM content determination is hard to meet the requirement.Based on the principle and methodology of CBM natural desorption,on the basis of the result of natural desorption,and under remaining the desorbed volume,gas composition and its content basically unchanged,the gas desorption rate is sped up reasonably and effectively by the use of continuous measuring and appropriately raising desorption temperature.Taking the determination analog between the rapid method and conventional natural desorption as a basis,the method of the rapid CBM content determination is built up.Comparatively,the application of rapid method will shorten the determining period to several days or even several hours,which is able to meet the demand for coal and CBM exploration.
2010, 38(1): 33-36.
DOI: 10.3969/j.issn.1001-1986.2010.01.008
Abstract：
Based on the analysis of samples from coal gangue,soil and leached water around gangue pile,it was found that the background content of total nitrogen in coal gangue is about 0.4%~0.8%,but the total nitrogen content in ammonium illite-bearing gangue is up to 1.0%~1.6%.So that,the existence of ammonium illite in the area of high metamorphic coal will contribute to the elevated nitrogen content.The leached water around coal gangue has high content of nitrogen,which shows that the nitrogen in the gangue is easy to be leached out by rain.The soil around the coal gangue has lower nitrogen content,which shows that leached water does not flow laterally,but possibly infiltres vertically,which may cause potential nitrogen pollution.
Based on the analysis of samples from coal gangue,soil and leached water around gangue pile,it was found that the background content of total nitrogen in coal gangue is about 0.4%~0.8%,but the total nitrogen content in ammonium illite-bearing gangue is up to 1.0%~1.6%.So that,the existence of ammonium illite in the area of high metamorphic coal will contribute to the elevated nitrogen content.The leached water around coal gangue has high content of nitrogen,which shows that the nitrogen in the gangue is easy to be leached out by rain.The soil around the coal gangue has lower nitrogen content,which shows that leached water does not flow laterally,but possibly infiltres vertically,which may cause potential nitrogen pollution.
2010, 38(1): 37-40.
DOI: 10.3969/j.issn.1001-1986.2010.01.009
Abstract：
In this paper,fourth silt clay in Shanhai was remolded to carry out experiment of direct shear,namely consolidation quick shear and slow shear,the curves of shear stress and shear strength were analyzed in summary.The normalized curves of its shearing stress and shear displacement were also analyzed,and the normalization equation was obtained,the relations between shear strength and water content of the shearing failure were discussed.
In this paper,fourth silt clay in Shanhai was remolded to carry out experiment of direct shear,namely consolidation quick shear and slow shear,the curves of shear stress and shear strength were analyzed in summary.The normalized curves of its shearing stress and shear displacement were also analyzed,and the normalization equation was obtained,the relations between shear strength and water content of the shearing failure were discussed.
2010, 38(1): 41-44.
DOI: 10.3969/j.issn.1001-1986.2010.01.010
Abstract：
FAAS(Flame Atomic Absorption Spectrometry) has already been widely used to many fields.However,due to several problems such as too many samples required,too long digested time and more interferers during the FAAS experiment,its use in practice is limited.In order to solve these problems,a new method using the FAAS to determine Zn、Cu、Fe、Mg、Ca、K and Na,seven element contents of soil samples in coal mining area after digested by HNO3-HClO4 is established in this paper after doing trial and error,combining with the characters of these samples.The method is easy and rapid with satisfied results.The relative standard deviations of these soil samples from Huainan coal mining area are less than 2.9%,while the recoveries of the additional standard are in the range of 97.3%~112.5%.
FAAS(Flame Atomic Absorption Spectrometry) has already been widely used to many fields.However,due to several problems such as too many samples required,too long digested time and more interferers during the FAAS experiment,its use in practice is limited.In order to solve these problems,a new method using the FAAS to determine Zn、Cu、Fe、Mg、Ca、K and Na,seven element contents of soil samples in coal mining area after digested by HNO3-HClO4 is established in this paper after doing trial and error,combining with the characters of these samples.The method is easy and rapid with satisfied results.The relative standard deviations of these soil samples from Huainan coal mining area are less than 2.9%,while the recoveries of the additional standard are in the range of 97.3%~112.5%.
2010, 38(1): 45-49.
DOI: 10.3969/j.issn.1001-1986.2010.01.011
Abstract：
The relationships among equivalent load,effective stress increment,water content,pore ratio and struccrease.The bigger the water content and the pore ratio are,the lower the structure strength of hydraulic fill is.It is considered that the formation of structure strength of hydraulic fill is closely related to its drainage concretion.The drainage concretion process of hydraulic fill includes forepart air discharge,penetrating concretion in vacuum ture strength were studied to probe the factors influencing the structure strength growth,the result shows that with increasement of effective stress increment and equivalent load,structure strength of hydraulic fill tends to in-seepage field and water gasification discharge under the vacuum condition.
The relationships among equivalent load,effective stress increment,water content,pore ratio and struccrease.The bigger the water content and the pore ratio are,the lower the structure strength of hydraulic fill is.It is considered that the formation of structure strength of hydraulic fill is closely related to its drainage concretion.The drainage concretion process of hydraulic fill includes forepart air discharge,penetrating concretion in vacuum ture strength were studied to probe the factors influencing the structure strength growth,the result shows that with increasement of effective stress increment and equivalent load,structure strength of hydraulic fill tends to in-seepage field and water gasification discharge under the vacuum condition.
2010, 38(1): 50-53.
DOI: 10.3969/j.issn.1001-1986.2010.01.012
Abstract：
Because of complicated engineering geology conditions and big load of upper structure in road construction of mountainous area,large deformation of bridge pile foundation appears,and the problem can not be solved very well.So deformation control of bridge pile foundation is very important in high frusta bridge design.Artificial dug pile foundation have been simulated by three-dimensional finite element method in the paper,then horizontal displacement and settlement were given.According to numerical simulation results,reinforced function and effect have been analyzed,horizontal displacement and settlement of pile foundation which have been reinforced by anchor pole(cable) were reduced effectively,and its project investment was reduced largely,and then the method provided a good way for similar projects.
Because of complicated engineering geology conditions and big load of upper structure in road construction of mountainous area,large deformation of bridge pile foundation appears,and the problem can not be solved very well.So deformation control of bridge pile foundation is very important in high frusta bridge design.Artificial dug pile foundation have been simulated by three-dimensional finite element method in the paper,then horizontal displacement and settlement were given.According to numerical simulation results,reinforced function and effect have been analyzed,horizontal displacement and settlement of pile foundation which have been reinforced by anchor pole(cable) were reduced effectively,and its project investment was reduced largely,and then the method provided a good way for similar projects.
2010, 38(1): 54-57.
DOI: 10.3969/j.issn.1001-1986.2010.01.013
Abstract：
Rapid discrimination of the water bursting sources is the precondition of preventing water-inrush from coal floor effectively.This paper puts forward a method for determining the weighting coefficient,deviation weighing method with reference to a deviation decomposition method in variance analysis,in the light of the shortages of the "super weighting method" and "biasing weighting method" that are commonly used to determine the weighting coefficient of the judging factors for solving the discrimination of the water bursting sources with the fuzzy comprehensive evaluation;Using SPSS,the example of Huainan Pansan mine had been studied with the three fuzzy models.The results show that the fuzzy comprehensive evaluation based on the deviation weighing method which has an advantage of "super weighting method" and "biasing weighting method" can make the discrimination of the water bursting sources more effective.Considering its characters such as clear principle,simple structure and more suitability,the fuzzy comprehensive evaluation based on the deviation weighing method suits for rapid discrimination of the water bursting sources and provides an assistant means for decision-making to prevent water-inrush from coal floor.
Rapid discrimination of the water bursting sources is the precondition of preventing water-inrush from coal floor effectively.This paper puts forward a method for determining the weighting coefficient,deviation weighing method with reference to a deviation decomposition method in variance analysis,in the light of the shortages of the "super weighting method" and "biasing weighting method" that are commonly used to determine the weighting coefficient of the judging factors for solving the discrimination of the water bursting sources with the fuzzy comprehensive evaluation;Using SPSS,the example of Huainan Pansan mine had been studied with the three fuzzy models.The results show that the fuzzy comprehensive evaluation based on the deviation weighing method which has an advantage of "super weighting method" and "biasing weighting method" can make the discrimination of the water bursting sources more effective.Considering its characters such as clear principle,simple structure and more suitability,the fuzzy comprehensive evaluation based on the deviation weighing method suits for rapid discrimination of the water bursting sources and provides an assistant means for decision-making to prevent water-inrush from coal floor.
2010, 38(1): 58-61.
DOI: 10.3969/j.issn.1001-1986.2010.01.014
Abstract：
The geothermometer is often used to calculate the deep temperatures of geothermal reservoirs in the geothermal system,but the temperatures calculated by different geothermometers are different,which needs to exam the mineral-fluid equilibrium state.The conditions for use of geothermometers in the geothermal system were discussed in the paper by taking the geothermal system in pingdingshan 8th mine as example.The Na-K-Ca diagram and lg(Q/K) figure were used to exam the mineral-fluid equilibrium state of the geothermal system in Pingdingshan 8th mine,which indicated that the chalcedony geothermometer was the most suitable geothermometer for the deep reservior in Pingdingshan 8th mine,and the temperature of the deep reserviors is about 50℃.
The geothermometer is often used to calculate the deep temperatures of geothermal reservoirs in the geothermal system,but the temperatures calculated by different geothermometers are different,which needs to exam the mineral-fluid equilibrium state.The conditions for use of geothermometers in the geothermal system were discussed in the paper by taking the geothermal system in pingdingshan 8th mine as example.The Na-K-Ca diagram and lg(Q/K) figure were used to exam the mineral-fluid equilibrium state of the geothermal system in Pingdingshan 8th mine,which indicated that the chalcedony geothermometer was the most suitable geothermometer for the deep reservior in Pingdingshan 8th mine,and the temperature of the deep reserviors is about 50℃.
2010, 38(1): 62-65,70.
DOI: 10.3969/j.issn.1001-1986.2010.01.015
Abstract：
The propagator matrix approach Abo-Zena based on the dispersion equation of Rayleigh wave could only be used for studying dispersion characteristics of layered media.For non-layered media,the propagator matrix approach was useless,and the finite-element method and the finite-difference method had to be considered.The authors applied the finite-difference method to simulate full-wave-fields in an infinite half-space filled with homogeneous elastic solid medium.The modeling program was written out in Matlab environment.The propagation characteristics of Rayleigh wave reappeared in snaps.A kind of algorithm to draw and fill the wiggle curves of the seismic synthetic records was also achieved,and more realistic seismograms were obtained.According to the modeling results,there is serious numerical dispersion by using one order finite-difference method,and the numerical dispersion must be suppressed when zigzag dispersion will be studied by finite-difference method in the future.Then,more realistic dispersion curves can be obtained.
The propagator matrix approach Abo-Zena based on the dispersion equation of Rayleigh wave could only be used for studying dispersion characteristics of layered media.For non-layered media,the propagator matrix approach was useless,and the finite-element method and the finite-difference method had to be considered.The authors applied the finite-difference method to simulate full-wave-fields in an infinite half-space filled with homogeneous elastic solid medium.The modeling program was written out in Matlab environment.The propagation characteristics of Rayleigh wave reappeared in snaps.A kind of algorithm to draw and fill the wiggle curves of the seismic synthetic records was also achieved,and more realistic seismograms were obtained.According to the modeling results,there is serious numerical dispersion by using one order finite-difference method,and the numerical dispersion must be suppressed when zigzag dispersion will be studied by finite-difference method in the future.Then,more realistic dispersion curves can be obtained.
2010, 38(1): 66-70.
DOI: 10.3969/j.issn.1001-1986.2010.01.016
Abstract：
Noise attenuation of seismic data processing is one of the key questions that can not be ignored.According to the nonlinear approximation property of the Curvelet transform in objects with piecewise C2 edges,a threshold method of random noise attenuation in seismic data is proposed based on the Curvelet transform.And an estimation approach of the threshold value is presented on the assumption that the random noise is independent and identically distributed Gaussian white noise.The synthetic data and post-stack real data processing results confirm the effectiveness of the proposed method.
Noise attenuation of seismic data processing is one of the key questions that can not be ignored.According to the nonlinear approximation property of the Curvelet transform in objects with piecewise C2 edges,a threshold method of random noise attenuation in seismic data is proposed based on the Curvelet transform.And an estimation approach of the threshold value is presented on the assumption that the random noise is independent and identically distributed Gaussian white noise.The synthetic data and post-stack real data processing results confirm the effectiveness of the proposed method.
2010, 38(1): 71-75.
DOI: 10.3969/j.issn.1001-1986.2010.01.017
Abstract：
Ground radar wave propagation in ground is influenced by the attenuation,dispersion and other interference,to certain extent,which will limit ground radar detection resolution and final interpretation effect.In order to reduce the attenuation,dispersion and the impact of interference,this paper presented a frequency compensation and correction method,which was based on the stratum system response model,through computing a frequency compensation and correction factor from the ground penetrating radar raw data,the raw recorder spectrum will be corrected,which will improve the ground penetrating radar profile record and enhance the vertical detection resolution.For better understanding of the effect of the stratum spectrum correction method,this article gave detailed introduction of its principle and application effect,but also compared its effect with that of sharp pulse deconvolution,which can further prove that the stratum spectrum correction method has advantage in reducing noise and enhancing resolution of the ground penetrating radar data.
Ground radar wave propagation in ground is influenced by the attenuation,dispersion and other interference,to certain extent,which will limit ground radar detection resolution and final interpretation effect.In order to reduce the attenuation,dispersion and the impact of interference,this paper presented a frequency compensation and correction method,which was based on the stratum system response model,through computing a frequency compensation and correction factor from the ground penetrating radar raw data,the raw recorder spectrum will be corrected,which will improve the ground penetrating radar profile record and enhance the vertical detection resolution.For better understanding of the effect of the stratum spectrum correction method,this article gave detailed introduction of its principle and application effect,but also compared its effect with that of sharp pulse deconvolution,which can further prove that the stratum spectrum correction method has advantage in reducing noise and enhancing resolution of the ground penetrating radar data.
2010, 38(1): 76-80.
DOI: 10.3969/j.issn.1001-1986.2010.01.018
Abstract：
The multi-scale analysis can effectively describe the signal characteristics in different scales efficiently and is widely used in signal processing.Curvelet transform is characterized by optimum sparseness constraint condition that can deal with line-like phenomena in high dimension.Through analyzing the signal characteristic in Curvelet domain among different waves,we think they have significant difference in frequency,angle and position.So we can employ Curvelet transform to separate interference wave from effective wave.Examples of processing the model data and field data illustrate its feasibility and effectiveness in wave separation,it can provide superior interference wave attenuation with minimal impact on the desirable signal components,and its result has good fidelity.
The multi-scale analysis can effectively describe the signal characteristics in different scales efficiently and is widely used in signal processing.Curvelet transform is characterized by optimum sparseness constraint condition that can deal with line-like phenomena in high dimension.Through analyzing the signal characteristic in Curvelet domain among different waves,we think they have significant difference in frequency,angle and position.So we can employ Curvelet transform to separate interference wave from effective wave.Examples of processing the model data and field data illustrate its feasibility and effectiveness in wave separation,it can provide superior interference wave attenuation with minimal impact on the desirable signal components,and its result has good fidelity.
