钻孔雷达探测金属矿的数值模拟
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摘要
矿产资源是制约一个国家经济和社会发展的重要因素之一,而其中原材料部分所用的矿产资源有很大一部分是金属矿,因此金属矿产的勘探开发对国民经济有着很大的作用。钻孔雷达在金属矿探测中,相对于传统钻孔地球物理方法有着横向探测范围大,分辨率高的优点,将越来越多的应用于金属矿探测中。
本文利用时域有限差分法(FDTD)采用数值模拟手段对钻孔雷达探测进行了正演模拟,通过对不同探测形式主要包括单孔反射测量和跨孔测量以及对不同形态的金属矿体主要包括等轴状体、板状体、柱状体和一个实际矿体的数值模拟,观测其数值模拟结果并进行必要的数据处理。通过对结果进行对比分析,说明了单孔反射测量对于探测等轴状体、板状体、柱状体和实际矿体具有良好的效果,不仅可以确定矿体的位置,而且对矿体形态也具有很好的识别性;跨孔反射测量对于探测等轴状体、板状体、柱状体也具有良好的效果,利用交会法可以确定出等轴状体的位置和形态,对板状体和柱状体的位置也能准确确定。
Mineral resources are very important to the economy and development. At present in our country about 80 present of raw and processed materials and 96 present of energy sources are come from mineral resources. Most part of mineral resources used as raw and processed materials are mining. So the exploration of mining is very important to the economy.
Borehole radar detects the high ground medium basing on high frequency electromagnetic. In China at present, there are not very much applications of using borehole radar to detect mining. The bore-radar can detect in the borehole, and it has higher resolution. The borehole radar can detect larger horizontal range, and it also can receive more strata information. These excellences make borehole radar playing a important part in mining exploration, especially in detailed investigation and exploration of blind ore body.
Bore–hole radar has three survey methods. They are single-hole reflection, cross-hole survey and surface-borehole survey. In this paper we use FDTD to simulate the borehole radar detection. We simulate the single-hole reflection and cross-hole survey. Taking into account the output of three-dimensional body can be Orebody (refers to solid mineral) is divided into three categories, namely, equiaxed-like, tabular and columnar. Axis of the body such as fingers roughly balanced three-dimensional extension of the ore body; tabular ore body refers to the direction of the two (length, width) and the other an extension of a larger direction (thickness) on the extension of a smaller body ; pole in one direction means an extension of a very long (up to 100m vertical depth and above) the direction of extension of two other very short (often round or oval) of the ore body. In order to output a variety of different simulated ore body, and from time to time in order to simplify the general model, this article were spherical body, instead of thin rectangular and cylindrical bodies of the three forms of output. Ore bodies have different outputs in addition to its occurrence and drilling the relative spatial location different from the probe will have different results.
The target used in this paper has low resistance and high dielectric constant. This is similar with mining. First we simulate the single-hole reflection. When the target is spherical bodies, in the profile the direct wave and reflect wave are in focus. The direct wave is linear. The reflect wave is hyperbolic. Using migration, we get the figure and the position of the target. When the target is plate body, we chose two representational models, one is the borehole cross the target, the other is the borehole perpendicular the target strike. When the borehole cross the target, the direct wave is cut, and blind spot appeared in the rear we can determine the drilling through the high dielectric constant and low resistance target, which is the main features of ore. When borehole does not pass through target but vertical the strike, the reflection wave is clear into hyperbolic curve shape. When the target is cylindrical body, we also chose two representational models, one is the borehole cross the target, the other is the borehole perpendicular the target strike. When the borehole cross the target, the direct wave is cut, and blind spot appeared in the rear we can determine the drilling through the high dielectric constant and low resistance target, which is the main features of ore. When borehole does not pass through target but vertical the strike, the reflection wave is clear into hyperbolic curve shape. Finally, a simulation of the actual deposits, see the single-hole survey has good detect result to detect the complex geological conditions, the adoption of a comprehensive explanation of a number of bored, we can accurately determine the location and form of the deposits. Yet it must be noted is that the low resistance of the electromagnetic waves experience strong absorption, so the follow-up media can not be detected. By simulate he single-hole reflection surveys, it shows that the single-hole reflection surveys has very good results detecting deep underground target, when drilling through the target can also determine ore body of low resistance and high dielectric constant.
After simulating the single-hole survey, we simulate the cross-hole survey. The goal of a simple form, such as spherical bodies, plate body, and the cylindrical body, in the detection of cross-hole reflection mode, as a result of the different detection methods, analysis becomes very complicated, but still be able to roughly determine the depth of target location, and determine along the direction of the drilling target is a point or a certain extension. In order to accurately determine the target location and form, this article uses the intersection method. The shape and specific location of the target can gained, but the intersection method only have good identification where the target is planes in the plane of the two drilling, for example, spherical body.
The simulation results for the above can be seen: single-hole reflection surveys on the ground floor has a very good target identification, and through the drill hole through the target can be of high dielectric constant of the low resistance metal body for confirmation; cross-hole detection although the analysis is complex but has a very good effect on the simple target detection. So borehole radar is a very effective geophysical method, a necessary complement to electromagnetic methods and Logging. In the future borehole radar will play a important role.
本文利用时域有限差分法(FDTD)采用数值模拟手段对钻孔雷达探测进行了正演模拟,通过对不同探测形式主要包括单孔反射测量和跨孔测量以及对不同形态的金属矿体主要包括等轴状体、板状体、柱状体和一个实际矿体的数值模拟,观测其数值模拟结果并进行必要的数据处理。通过对结果进行对比分析,说明了单孔反射测量对于探测等轴状体、板状体、柱状体和实际矿体具有良好的效果,不仅可以确定矿体的位置,而且对矿体形态也具有很好的识别性;跨孔反射测量对于探测等轴状体、板状体、柱状体也具有良好的效果,利用交会法可以确定出等轴状体的位置和形态,对板状体和柱状体的位置也能准确确定。
Mineral resources are very important to the economy and development. At present in our country about 80 present of raw and processed materials and 96 present of energy sources are come from mineral resources. Most part of mineral resources used as raw and processed materials are mining. So the exploration of mining is very important to the economy.
Borehole radar detects the high ground medium basing on high frequency electromagnetic. In China at present, there are not very much applications of using borehole radar to detect mining. The bore-radar can detect in the borehole, and it has higher resolution. The borehole radar can detect larger horizontal range, and it also can receive more strata information. These excellences make borehole radar playing a important part in mining exploration, especially in detailed investigation and exploration of blind ore body.
Bore–hole radar has three survey methods. They are single-hole reflection, cross-hole survey and surface-borehole survey. In this paper we use FDTD to simulate the borehole radar detection. We simulate the single-hole reflection and cross-hole survey. Taking into account the output of three-dimensional body can be Orebody (refers to solid mineral) is divided into three categories, namely, equiaxed-like, tabular and columnar. Axis of the body such as fingers roughly balanced three-dimensional extension of the ore body; tabular ore body refers to the direction of the two (length, width) and the other an extension of a larger direction (thickness) on the extension of a smaller body ; pole in one direction means an extension of a very long (up to 100m vertical depth and above) the direction of extension of two other very short (often round or oval) of the ore body. In order to output a variety of different simulated ore body, and from time to time in order to simplify the general model, this article were spherical body, instead of thin rectangular and cylindrical bodies of the three forms of output. Ore bodies have different outputs in addition to its occurrence and drilling the relative spatial location different from the probe will have different results.
The target used in this paper has low resistance and high dielectric constant. This is similar with mining. First we simulate the single-hole reflection. When the target is spherical bodies, in the profile the direct wave and reflect wave are in focus. The direct wave is linear. The reflect wave is hyperbolic. Using migration, we get the figure and the position of the target. When the target is plate body, we chose two representational models, one is the borehole cross the target, the other is the borehole perpendicular the target strike. When the borehole cross the target, the direct wave is cut, and blind spot appeared in the rear we can determine the drilling through the high dielectric constant and low resistance target, which is the main features of ore. When borehole does not pass through target but vertical the strike, the reflection wave is clear into hyperbolic curve shape. When the target is cylindrical body, we also chose two representational models, one is the borehole cross the target, the other is the borehole perpendicular the target strike. When the borehole cross the target, the direct wave is cut, and blind spot appeared in the rear we can determine the drilling through the high dielectric constant and low resistance target, which is the main features of ore. When borehole does not pass through target but vertical the strike, the reflection wave is clear into hyperbolic curve shape. Finally, a simulation of the actual deposits, see the single-hole survey has good detect result to detect the complex geological conditions, the adoption of a comprehensive explanation of a number of bored, we can accurately determine the location and form of the deposits. Yet it must be noted is that the low resistance of the electromagnetic waves experience strong absorption, so the follow-up media can not be detected. By simulate he single-hole reflection surveys, it shows that the single-hole reflection surveys has very good results detecting deep underground target, when drilling through the target can also determine ore body of low resistance and high dielectric constant.
After simulating the single-hole survey, we simulate the cross-hole survey. The goal of a simple form, such as spherical bodies, plate body, and the cylindrical body, in the detection of cross-hole reflection mode, as a result of the different detection methods, analysis becomes very complicated, but still be able to roughly determine the depth of target location, and determine along the direction of the drilling target is a point or a certain extension. In order to accurately determine the target location and form, this article uses the intersection method. The shape and specific location of the target can gained, but the intersection method only have good identification where the target is planes in the plane of the two drilling, for example, spherical body.
The simulation results for the above can be seen: single-hole reflection surveys on the ground floor has a very good target identification, and through the drill hole through the target can be of high dielectric constant of the low resistance metal body for confirmation; cross-hole detection although the analysis is complex but has a very good effect on the simple target detection. So borehole radar is a very effective geophysical method, a necessary complement to electromagnetic methods and Logging. In the future borehole radar will play a important role.
引文
[1]柴东浩.地球科学的100个基本问题[M].陕西:山西科学技术出版社,2004.
[2]曾昭发,刘四新,王者江,薛建.探地雷达方法原理及应用[M].北京:科学出版社,2006.
[3]黄家会,宋雷,陈先德,崔广心,杨维好.地下深部灰岩岩石特性的单孔雷达反射研究[J].水文地质工程地质,1996,23(6) :57-59.
[4]王驹,陈伟明,张鹏,郭永海,苏锐.钻孔雷达在高放废物处置库场址评价中的应用—以北山1号孔为例[J].铀矿地质,2005,21(6):360-363.
[5] Peter K. Fullagar, Dean Liveybrooks, Ping Zhang, Andrew Calvert, and Yiren Wu. The Proceeding of the Tenth International Conference on Ground Penetrating Radar. IEEE, 2004[C]. The Netherlands, 21-24.
[6]王兴泰,赵翼忱,陈森鑫.水文工程地球物理勘探[M].长春:长春地质学院工程物探教研室,1982.
[7]粟毅,黄春琳,雷文太.探地雷达理论及应用[M],科学出版社,2006,46-47.
[8]钟声.钻孔雷达于数字摄像动态勘察技术若干关键问题研究[D].武汉:中科院武汉岩土力学研究所,2008.
[9]陈建胜,陈从新.钻孔雷达于数字摄像动态勘察技术若干关键问题研究[D].武汉:中科院武汉岩土力学研究所,2008.
[10]粟毅,黄春琳,雷文太.探地雷达理论及应用[M],科学出版社,2006.
[11]何樵登,熊维纲主编.应用地球物理教程-地震勘探[M],长春:吉林大学出版社,2004.
[12]黄伟,邓世坤,偏移方法用于探地雷达图像处理的有效性研究[J],地质科技情报,2001,20(4):99-102.
[13]薛桂霞,刘秀娟,邓世坤.雷达波偏移方法研究[J],地球物理学进展,2004,19(4):903-908.
[14]郑海山.地震偏移技术研究进展[J],世界地质,2000,19(4) :392-401.
[15]仝传雪.探地雷达极化测量响应研究[D].吉林:吉林大学,2007.
[16]王春辉.探地雷达方法测量近地表含水量及污染物探测研究[D].吉林:吉林大学,2007.
[17]冯彦谦.机载探地雷达探测地下目标体的数值仿真于成像研究[D].吉林:吉林大学,2008.
[18]杨薇.基于弯曲射线的跨孔层析成像算法研究[D].吉林:吉林大学,2008.
[19]杨保祥.攀枝花矿产资源特征及循环经济发展策略探讨[J].四川有色金属,2006,01(06):1-5.
[20]郑永春,欧阳自远,王世杰,等.微扰法测量干燥岩矿样品复介电常数[J].地球科学,2006,31(6):867-872.
[21] Iain M.Mason, Andrew J.Bray, Tim G.Sindle, Carina M.Simmat, and Johannes H.Cloete. The Effect of Conduction on VHF Radar Images Shot in Water-Filled Boreholes[J]. IEEE Geoscience and remote sensing letters, 2008,5(2):304-307.
[22] Peter K.Fullagar, Dean W.Livelybrooks, Ping Zhang, Andrew J.Calver and Yiren Wu. Radio tomography and borehole radar delineation of the McConnell nickel sulfide deposit, Sudbury, Ontario, Canada[J]. 2000, 65(6):1920-1930.
[23] Pradip Kumar Mukhopadhyay.Three-dimensional boreradar imaging[D]. Cape Town: University of Cape Town:2005.
[24] K.Holliger, M.Musil, H.R.Maurer. Ray-based amplitude tomography for crosshole georadar data: a numerical assessment[J]. Journal of Applied Geophysics,47(2001):285-298.
[25] Barry J.Drummond, Bruce R.Goleby, A.J.Owen, et al. Seismic reflection imaging of mineral system: Three case histories[J]. Geophysics, 65(6): 1852-1861.
[26]刘四新,曾昭发,徐波.利用钻孔雷达探测地下含水裂缝[J].地球物理学进展,2006,21(2):620-624.
[27]刘四新,曾昭发,徐波.钻孔雷达探测地下裂缝[J].吉林大学学报(地球科学版),2005,35:128-131.
[28] Tong Xu, George A.McMechan. GPR attenuation and its numerical simulation in 2.5 dimensions[J]. Geophysics,1997,62(1):403-414.
[29]葛德彪,阎玉波,电磁波时域有限差分方法[M],西安:电子科技大学出版社,2001.
[30] Stanislav Vitebskiy, Lawrence Carin, Marc A.Ressler, and Francis H.Le. Ultra-Wideband, Short-Pulse Ground-Penetrating Radar: Simulation and Measurement[C], IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, 35(3), MAY 1997.
[31] Abdelhak M. Zoubir, Ian James Chant, Christopher L.Brown. Signal Processing Techniques for Landmine Detection Using Impulse Ground Penetrating Radar[J], IEEE SENSORS JOURNAL, 2002,2(1):221-227
[32] Antonis Giannopoulos, Modelling ground penetrating radar by GprMax[J], Construction and Building Materials, 2005, 22:755-762.
[33] How-Wei Chen, Tai-Min Huang, Finite-difference time-domain simulation of GPR data[J], Journal of Applied Geophysics, 1998, 39:139-163.
[34] James Irving, Rosemary Knight, Numerical modeling of ground penetrating radar in 2-D using MATLAB[J], Computers and Geosciences, 2006, 33:1247-1258.
[2]曾昭发,刘四新,王者江,薛建.探地雷达方法原理及应用[M].北京:科学出版社,2006.
[3]黄家会,宋雷,陈先德,崔广心,杨维好.地下深部灰岩岩石特性的单孔雷达反射研究[J].水文地质工程地质,1996,23(6) :57-59.
[4]王驹,陈伟明,张鹏,郭永海,苏锐.钻孔雷达在高放废物处置库场址评价中的应用—以北山1号孔为例[J].铀矿地质,2005,21(6):360-363.
[5] Peter K. Fullagar, Dean Liveybrooks, Ping Zhang, Andrew Calvert, and Yiren Wu. The Proceeding of the Tenth International Conference on Ground Penetrating Radar. IEEE, 2004[C]. The Netherlands, 21-24.
[6]王兴泰,赵翼忱,陈森鑫.水文工程地球物理勘探[M].长春:长春地质学院工程物探教研室,1982.
[7]粟毅,黄春琳,雷文太.探地雷达理论及应用[M],科学出版社,2006,46-47.
[8]钟声.钻孔雷达于数字摄像动态勘察技术若干关键问题研究[D].武汉:中科院武汉岩土力学研究所,2008.
[9]陈建胜,陈从新.钻孔雷达于数字摄像动态勘察技术若干关键问题研究[D].武汉:中科院武汉岩土力学研究所,2008.
[10]粟毅,黄春琳,雷文太.探地雷达理论及应用[M],科学出版社,2006.
[11]何樵登,熊维纲主编.应用地球物理教程-地震勘探[M],长春:吉林大学出版社,2004.
[12]黄伟,邓世坤,偏移方法用于探地雷达图像处理的有效性研究[J],地质科技情报,2001,20(4):99-102.
[13]薛桂霞,刘秀娟,邓世坤.雷达波偏移方法研究[J],地球物理学进展,2004,19(4):903-908.
[14]郑海山.地震偏移技术研究进展[J],世界地质,2000,19(4) :392-401.
[15]仝传雪.探地雷达极化测量响应研究[D].吉林:吉林大学,2007.
[16]王春辉.探地雷达方法测量近地表含水量及污染物探测研究[D].吉林:吉林大学,2007.
[17]冯彦谦.机载探地雷达探测地下目标体的数值仿真于成像研究[D].吉林:吉林大学,2008.
[18]杨薇.基于弯曲射线的跨孔层析成像算法研究[D].吉林:吉林大学,2008.
[19]杨保祥.攀枝花矿产资源特征及循环经济发展策略探讨[J].四川有色金属,2006,01(06):1-5.
[20]郑永春,欧阳自远,王世杰,等.微扰法测量干燥岩矿样品复介电常数[J].地球科学,2006,31(6):867-872.
[21] Iain M.Mason, Andrew J.Bray, Tim G.Sindle, Carina M.Simmat, and Johannes H.Cloete. The Effect of Conduction on VHF Radar Images Shot in Water-Filled Boreholes[J]. IEEE Geoscience and remote sensing letters, 2008,5(2):304-307.
[22] Peter K.Fullagar, Dean W.Livelybrooks, Ping Zhang, Andrew J.Calver and Yiren Wu. Radio tomography and borehole radar delineation of the McConnell nickel sulfide deposit, Sudbury, Ontario, Canada[J]. 2000, 65(6):1920-1930.
[23] Pradip Kumar Mukhopadhyay.Three-dimensional boreradar imaging[D]. Cape Town: University of Cape Town:2005.
[24] K.Holliger, M.Musil, H.R.Maurer. Ray-based amplitude tomography for crosshole georadar data: a numerical assessment[J]. Journal of Applied Geophysics,47(2001):285-298.
[25] Barry J.Drummond, Bruce R.Goleby, A.J.Owen, et al. Seismic reflection imaging of mineral system: Three case histories[J]. Geophysics, 65(6): 1852-1861.
[26]刘四新,曾昭发,徐波.利用钻孔雷达探测地下含水裂缝[J].地球物理学进展,2006,21(2):620-624.
[27]刘四新,曾昭发,徐波.钻孔雷达探测地下裂缝[J].吉林大学学报(地球科学版),2005,35:128-131.
[28] Tong Xu, George A.McMechan. GPR attenuation and its numerical simulation in 2.5 dimensions[J]. Geophysics,1997,62(1):403-414.
[29]葛德彪,阎玉波,电磁波时域有限差分方法[M],西安:电子科技大学出版社,2001.
[30] Stanislav Vitebskiy, Lawrence Carin, Marc A.Ressler, and Francis H.Le. Ultra-Wideband, Short-Pulse Ground-Penetrating Radar: Simulation and Measurement[C], IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, 35(3), MAY 1997.
[31] Abdelhak M. Zoubir, Ian James Chant, Christopher L.Brown. Signal Processing Techniques for Landmine Detection Using Impulse Ground Penetrating Radar[J], IEEE SENSORS JOURNAL, 2002,2(1):221-227
[32] Antonis Giannopoulos, Modelling ground penetrating radar by GprMax[J], Construction and Building Materials, 2005, 22:755-762.
[33] How-Wei Chen, Tai-Min Huang, Finite-difference time-domain simulation of GPR data[J], Journal of Applied Geophysics, 1998, 39:139-163.
[34] James Irving, Rosemary Knight, Numerical modeling of ground penetrating radar in 2-D using MATLAB[J], Computers and Geosciences, 2006, 33:1247-1258.