Abstract
Edge detection is an image processing technique for finding the boundaries of objects within images. It is typically used to interpret gravity and magnetic data, and find the horizontal boundaries of geological bodies. Large deviations between model and true edges are common because of the interference of depth and errors in computing the derivatives; thus, edge detection methods cannot provide information about the depth of the source. To simultaneously obtain the horizontal extent and depth of geophysical anomalies, we use normalized edge detection filters, which normalize the edge detection function at different depths, and the maxima that correspond to the location of the source. The errors between model and actual edges are minimized as the depth of the source decreases and the normalized edge detection method recognizes the extent of the source based on the maxima, allowing for reliable model results. We demonstrate the applicability of the normalized edge detection filters in defining the horizontal extent and depth using synthetic and actual aeromagnetic data.
Similar content being viewed by others
References
Abdelrahman, E. M., 1990, Discussion on “A leastsquares approach to depth determination from gravity data” by O.P. Gupta: Geophysics, 55, 376–378.
Aydin, A., 1997, Evaluation of Gravity Data in Terms of Hydrocarbon by Normalized Full Gradient, Variation, and Statistic Methods, Model Studies and Application in Hasankale-Horasan Basin (Erzurum): Ph.D. Thesis, Karadeniz Technical Univ., Natural and Applied Sciences Institute, Trabzon, Turkey.
Aydin, A., 2005. Evaluation of Gravity Anomalies by Direct Interpretation Techniques: An Application from Hasankale-Horasan Region: Journal of Engineering Sciences, 11(1), 95–102.
Aydin, A., 2007, Interpretation of gravity anomalies with the normalized full gradient (NFG) method and an example: Pure and Applied Geophysics, 164(11), 2329–2344.
Berezkin, V.M., 1967, Application of the total vertical gradient of gravity for determination of the depths to the sources of gravity anomalies: Exploration Geophysics, 18, 69–79.
Blakely, R. J., 1995. Potential theory in gravity and magnetic applications: Cambridge University Press.
Cordell, L., 1979, Gravimetric expression of graben faulting in Santa Fe Country and the Espanola Basin, New Mexico. New Mexico Geol. Soc. Guidebook, 30th Field Conf., 59–64.
Cordell. L, and Grauch, V. J. S., 1985, Mapping basement magnetization zones from aeromagnetic data in the San Juan basin, New Mexico, in Hinzc. W. J. Ed., The utility of regional gravity and magnetic anomaly: Society of Exploration Geophysicists, 181–197.
Cooper, G. R. J., and Cowan, D. R.. 2006, Enhancing potential field data using filters based on the local phase: Computers & Geosciences, 32(10), 1585–1591.
Cooper, G. R. J., and Cowan, D. R., 2008, Edge enhancement of potential field data using normalized statistics: Geophysics, 73(3), H1–H4.
Cooper, G. R. J., 2009, Balancing images of potential field data: Geophysics, 74(3), L17–L20.
Elawadi, E., Salem, A., and Ushijima, K., 2001, Detection of cavities and tunnels from gravity data using a neural network: Exploration Geophysics, 32(4), 204–208.
Even, H. M., 1936, The place of the vertical gradient in gravitational interpretations: Geophysics, 1(1), 127–136.
Gao, F.H., Wang, F., and Cao, H.H., 2010, Zircon U-Pb Age of the Basement Granite from Suibin Depression in Sanjiang Basin and Its Tectonic Implications: Journal of Jilin University (Earth Science Edition), 40(4), 869–878.
Griffin, W.R., 1949, Residual gravity in theory and practice: Geophysics. 14(1), 39–56.
Ma, G.Q., Liu, C., Huang, D.N., et al., 2013, A stable iterative downward continuation of potential field data: Journal of Applied Geophysics, 98, 205–211.
Hartman, R. R., Teskey, D. J., and Friedberg, J. L., 1971, A system for rapid digital aeromagnetic interpretation: Geophysics, 36(5), 891–918.
Hood. P. J., and Tasked, D. J., 1989, Aeromagnetic gradiometer program of the Geological Survey of Canada: Geophysics, 54(8), 1012–1022.
Hsu, S., Sibuet, J. C., and Shyu, C., 1996, Highresolution detection of geologic boundaries from potential field anomalies: an enhanced analytic signal technique: Geophysics, 61(2), 373–386.
Miller, H.G., and Singh, V., 1994, Potential field tilt—a new concept for location of potential field sources: Journal of Applied Geophysics, 32(2–3), 213–217.
Ma, G.Q., Huang, D.N., Yu, P., et al., Huang Da-Nian, Yu, Ping et al., 2012, Application of improved balancing filters to edge identification of potential field data: Chinese J.Geophys., 55(12),4288–4295.
Ma, G.Q., 2013, Edge detection of potential field data using improved local phase filter: Exploration Geophysics, 44(1), 36–41.
Nabighian, M. N., 1972, The analytic signal of two-dimensional magnetic bodies with polygonal crosssection: its properties and use for automated anomaly interpretation: Geophysics, 37(3), 507–517.
Rajagopalan, S., and Milliganm P., 1995, Image enhancement of aeromagnetic data using automatic gain control: Exploration Geophysics, 25(4), 173–178.
Reid, A. B, Allsop, J. M., Granser, H, et al. 1990, Magnetic interpretation in three dimensions using Euler deconvolution: Geophysics, 55(1), 80–91.
Roest, W. R., Verhoef, J., and Pilkington, M., 1992, Magnetic interpretation using the 3-D analytic signal: Geophysics, 57(1), 116–125.
Salem, A., Ravat, D., Mushayandebvu, M. F., et al. 2004, Linearized least-squares method for interpretation of potential field data from sources of simple geometry: Geophysics, 69(3), 783–788.
Thompson, D. T., 1982, “EULDPH”—A new technique for making computer-assisted depth estimates from magnetic data: Geophysics, 47(1), 31–37.
Thurston, J. B., and Smith, R. S., 1997, Automatic conversion of magnetic data to depth, dip, and susceptibility contrast using the SPI method: Geophysics, 62(3), 807–813.
Verduzco, B., Fairhead, J. D., and Green, C. M., 2004, New insights into magnetic derivatives for structural mapping: The Leading Edge, 23(2), 116–119.
Wang, W.Y., Pan, Y., and Qiu, Z.Y., 2009, A new edge recognition technology based on the normalized vertical derivative of the total horizontal derivative for potential field data: Applied Geophysics, 6(3), 226–233
Wang, W.Y., 2010, Spatial variation law of the extreme value positions of total horizontal derivative for potential field data. Chinese Journal of Geophysics, 53(9), 2257–2270.
Wang, W.Y., Zhang, G.C., and Liang, J.S., 2010, Spatial variation law of vertical derivative zero points for potential field data: Applied Geophysics, 7(3), 197–209.
Wijns C, Perez C, Kowalczyk P., 2005, Theta map: edge detection in magnetic data: Geophysics, 70(4), 39–43.
Xiao, P.F., Li, M., and Xu, S.Z., 2006, Stable solution of normalized total gravity gradient: Oil Geophysics Prospecting, 41(5), 596–600.
Zeng, H., Meng, X., and Yao, C., 2002. Detection of reservoirs from normalized full gradient of gravity anomalies and its application to Shengli Oil Field, East China: Geophysics, 67(4), 1138–1147.
Author information
Authors and Affiliations
Corresponding author
Additional information
This research was financially supported by the China Postdoctoral Science Foundation (No.2014M551188) and the Deep Exploration in China Sinoprobe-09-01 (No.201011078)
Li Li-Li, lecturer, graduated from Jilin University in 2013 with a PhD in Solid Geophysics. Her research interests include the processing and interpretation of geophysical data.
Rights and permissions
About this article
Cite this article
Li, LL., Han, LG. & Huang, DN. Normalized edge detection, and the horizontal extent and depth of geophysical anomalies. Appl. Geophys. 11, 149–157 (2014). https://doi.org/10.1007/s11770-014-0436-2
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11770-014-0436-2