Laplacian of Gaussian Operator with rotation invariance and sensitive to gravity and magnetic field gradient mutation is isotropic second-order differential operator, which has nothing to do with geological boundary objects trend. By calculating the zero value of the Laplacian of Gaussian Operator, the authors delineated the boundary in potential field and extracted geological body distribution, characteristics of fracture structure plane distribution and other geological information. The application of numerical experiments to airborne gravity data indicates that the method can effectively determine the gravity and magnetic source boundaries with higher resolution and accurate positioning. Especially for the multi-sources overlapping geological structure with different depths, different scales and different attitudes, the method can clearly detect the boundaries of weak anomalies with relatively smooth gradient and adjacent local anomalies with superimposed interference. It also can provide more details for further improvement of fine interpretation of the gravity and magnetic local anomalies, and has certain significance for detecting the geological boundaries, devising tectonic units, and determining the fracture zone and the trend of geological structure. All this will facilitate the integrated interpretation.
王明, 何辉, 王林飞, 刘前坤. 高斯——拉普拉斯算子场源边界识别方法[J]. 物探与化探, 2015, 39(S1): 137-143.
WANG Ming, HE Hui, WANG Lin-Fei, LIU Qian-Kun. Laplacian of Gaussian Operator for Edge Detection. Geophysical and Geochemical Exploration, 2015, 39(S1): 137-143.
[1] Hood P, McClure D J. Gradient measurements in ground magnetic prospecting[J].Geophysics,1965, 30(3):403-410.[2] Bhattacharyya B K. Two-dimensional harmonic analysis as a tool for magnetic interpretation[J]. Geophysics, 1965 ,30(5):829-857.[3] Grauch V J S, Cordell L. Limitations of determining density or magnetic boundaries from the horizontal derivative of gravity or pseudogravity data[J].Geophysics,1987,52(1):118-121.[4] Roest W R, Verhoef J, Pilkington M. Magnetic interpretation using 3-D the analytic signal[J]. Geophysics,1992,57(1):116-125.[5] Atchuta Rao D, Ram Babu H V, Sanker Narayan P V. Interpretation of magnetic anomalies due to dikes: The complex gradient method[J].Geophysics,1981,46(11):1572-1578.[6] 余钦范,楼海.水平梯度法提取重磁源边界位置[J].物探化探计算技术,1994,16(4):363-367.[7] Fedi M, Florio G. Detection of potential fields source boundaries by enhanced horizontal derivative method[J]. Geophysical Prospecting,2001,49(1):40-58.[8] Wang W Y, Pan Y, Qiu Z Y. A new edge recognition technology based on the normalized vertical derivative of the total horizontal derivative for potential field data[J].Applied Geophysics, 2009,6(3):226-233.[9] 王万银.位场总水平导数极值位置空间变化规律研究[J].地球物理学报,2010,53(9): 2257-2270.[10] 钟清,孟小红,刘士毅.重力资料定位地质体边界问题的探讨[J].物探化探计算技术,2007,29(增刊):35-38.[11] 张恒磊,刘天佑,杨宇山.各向异性标准化方差计算重磁源边界[J].地球物理学报,2011,54(7): 1921-1927.[12] 张恒磊,Marangoni Y R,左仁广,等.改进的各向异性标准化方差探测斜磁化磁异常源边界[J].地球物理学报,2014,57(8):2724-2731.[13] Nabighian M N. The analytic signal of two-dimensional magnetic bodies with polygonal cross-section: Its properties and use for automated anomaly interpretation[J].Geophysics, 1972,37(3):507-517.[14] Miller H G, Singh V. Potential field tilt-A new concept for location of potential field sources[J].Journal of Applied Geophysics,1994,32(2):213-217.[15] Wijns C, Perez C, Kowalczyk P. Theta map: Edge detection in magnetic data[J].Geophysics,2005,70(4):L39-L43.[16] Cooper G R J, Cowan D R. Edge enhancement of potential-field data using normalized statistics[J]. Geophysics, 2008, 73(3):1-4.[17] Hsu S K, Sibuet J C, Shyu C T. High-resolution detection of geologic boundaries from potential-field anomalies: An enhanced analytic signal technique[J].Geophysics,1996,61(2):373-386.[18] Debeglia N, Corpel J. Automatic 3-D interpretation of potential field data using analytic signal derivatives[J].Geophysics,1997,62(1):87-96.[19] Bournas N, Baker H A. Interpretation of magnetic anomalies using the horizontal gradient analytic signal[J]. Annali Di Geofisica,2001,44(3):505-526.[20] 骆遥,王明,罗锋,等.重磁场二维希尔伯特变换—直接解析信号解释方法.地球物理学报,2011,54(7):1912-1920.[21] Verduzco B, Fairhead J D, Green C M, Mackenzie C. New insights into magnetic derivatives for structural mapping[J]. The Leading Edge,2004,23(2):116-119.[22] Salem A, Ravat D. A combined analytic signal and Euler method(AN-EUL)for automatic interpretation of magnetic data[J].Geophysics,2003,68(6):1952-1961.[23] Salem A, Smith R, Williams S, et al. Generalized magnetic tilt-Euler deconvolution[C].SEG Expanded Abstracts, 2007:790-794.[24] Nabighian M N. Additional comments on the analytic signal of two-dimensional magnetic bodies with polygonal cross-section[J].Geophysics,1974,39(1):85-92.[25] Nabighian M N. Toward a three-dimensional automatic interpretation of potential field data via generalized Hilbert transforms:Fundamental relations[J].Geophysics,1984,49(6):780-786.[26] Agarwal B N P, Shaw R K. Comment on "An analytic signal approach to the interpretation of total field magnetic anomalies" by Shuang Qin[J]. Geophysical Prospecting,1996,44(5):911-914.[27] 管志宁, 姚长利. 倾斜板体磁异常总梯度模反演方法[J]. 地球科学—中国地质大学学报,1997,22(1): 81-85.[28] Huang L P, Guan Z N, Yao C L. Comment on: "An analytic signal approach to the interpretation of total field magnetic anomalies" by Shuang Qin[J]. Geophysical Prospecting,1997,45(5): 879-881.[29] Huang L P, Guan Z N. Discussion on:"Magnetic interpretation using the 3-D analytic signal"[J]. Geophysics, 1998, 63(2): 667-670.[30] 黄临平,管志宁.利用磁异常总梯度模确定磁源边界位置[J].华东地质学院学报,1998,21(2):143-150.[31] Li X. Understanding 3D analytic signal amplitude[J].Geophysics,2006,71(2):L13-L16.[32] Ma G Q,Du X J.An improved analytic signal technique for the depth and structural index from 2D magnetic anomaly data[J].Pure and Applied Geophysics,2012,169(12):2193-2200.[33] Ma G Q, Du X J, Li L L,et al.Interpretation of magnetic anomalies by horizontal and vertical derivatives of the analytic signal[J].Applied Geophysics,2012,9(4):468-474.[34] Gordon R J,Cooper.Reducing the dependence of the analytic signal amplitude of aeromagnetic data on the source vector direction[J].2014,79(4):J55-J60.[35] 王万银.位场解析信号振幅极值位置空间变化规律研究[J]. 地球物理学报,2012,55(4):1288-1299.[36] Archibald N, Gow P, Boschetti F. Multiscal edge analysis of potential field data[J]. Exploration Geophysics,1999,30(2):38-44.[37] Holden D J, Archibald N J, Boschetti F, Jessell M W. Infering geological structures using wavelet-based multiscale edge analysis and forward models[J]. Exploration geophysics,2001, 31(4):67-71.[38] Marlet G, Sailhac P, Moreau F, Diament M. Characterization of geological boundaries using 1-D wavelet transform on gravity data: Theory and application to the Himalayas[J].Geophysics, 66(4):1116-1129.[39] Cooper G R J, Cowan D R. Enhancing potential field data using filters based on the local phase[J]. Computers & Geosciences,2006,32(10):1585-1591.[40] Zhang L L, Hao T Y, Wu J S, Wang J L. Application of image enhancement techniques to potential field data[J]. Applied Geophysics,2005,2(3):145-152.[41] Thompson D T. EULDPH-a new technique for making computer assisted depth estimates from magnetic data[J].Geophysics,1982,47(1):31-37.[42] Reid A B, Allsop J M, Granser H, et al. Magnetic interpretation in three dimensions using euler deconvolution[J].Geophysiscs,1990,55(1):80-91.[43] Thurston J B, Smith R S. Automatic conversion of magnetic data to depth, dip and susceptibility contrast using the SPI method[J]. Geophysics,1997,62(3):807-813.[44] Smith R S, Thurston J B, Dai T, MacLeod I N. iSPITM-the improved source parameter imaging method[J]. Geophysical Prospecting,1998,46:141-151.[45] 李文勇,周坚鑫,周锡华,等.航空重力局部异常地质成因分类及找矿意义[J].地球科学进展,2010, 25(10):1061-1069.
