Abstract
Edge detection is one of the most important steps in the map interpretation of potential field data. In such a dataset, it is difficult to distinguish adjacent anomalous sources due to their field superposition. In particular, the presence of overlain shallow and deep magnetic/gravity sources leads to strong and weak anomalies. In this paper, we present an improved filter, STDR, which utilises the ratio of the second-order vertical derivative to the second-order total horizontal derivative at the tilt angle equation. The maximum and minimum values of this filter delineate the positive and negative anomalies, respectively. This novel filtering approach normalises the intensity of strong and weak anomalies, as well as anomalies with different depths and properties. Moreover, to better illustrate the edges, its total horizontal derivative (THD_STDR) is also used. For positive and negative anomalies, the maximum value of the THD_STDR filter shows the edges of the anomalies. The potentiality of the proposed method is examined through both synthetic and real case scenarios and the results are compared with a number of existing edge detector filters, namely TDR, THD_TDR, Theta and TDX. Due to substantial improvements in the filtering, STDR and its total horizontal derivative allow for more accurate estimation of anomaly edges in comparison with the other filtering techniques. As a consequence, the interpretation of the potential field data is more feasible using the STDR filtering method.
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References
Blakely, R. J. (1995). Potential theory in gravity and magnetic applications (p. 441). Cambridge: Cambridge University Press.
Blakely, R. J., & Simpson, R. W. (1986). Approximating edges of source bodies from magnetic or gravity anomalies. Geophysics, 51(7), 1494–1498.
Cooper, G. R. J., & Cowan, D. R. (2004). The detection of circular features in irregularly spaced data. Computers and Geosciences, 30(1), 101–105.
Cooper, G. R. J., & Cowan, D. R. (2006). Enhancing potential field data using filters based on the local phase. Computers and Geosciences, 32(10), 1585–1591.
Cordell, L. (1979). Gravimetric expression of graben faulting in Santa Fe country and the Espanola basin, New Mexico. New Mexico Geological Society Guidebook, 30th Field Conference, pp. 59–64.
Cordell, L., Grauch, V.J.S. (1985). Mapping basement magnetization zones from aeromagnetic data in the San Juan Basin, New Mexico. The Utility of Regional Gravity and Magnetic Anomaly Maps, pp. 181–197.
Daly, J. S., Balagansky, V. V., Timmerman, M. J., & Whitehouse, M. J. (2006). The Lapland–Kola orogen: Palaeoproterozoic collision and accretion of the northern Fennoscandian lithosphere. Geological Society, London, Memoirs, 32(1), 579–598.
EON Geosciences Inc. (2015). Troms-Finnmark fixed wing aeromagnetic survey 2014 (TROFI-14) (p. 34). Montréal: Report EON Geosciences.
Evjen, H. M. (1936). The place of the vertical gradient in gravitational interpretations. Geophysics, 1(1), 127–136.
Fedi, M., & Florio, G. (2001). Detection of potential fields source boundaries by enhanced horizontal derivative method. Geophysical Prospecting, 49(1), 40–58.
Ferreira, F. J., de Souza, J., de Bongiolo, B. E. S. A., & de Castro, L. G. (2013). Enhancement of the total horizontal gradient of magnetic anomalies using the tilt angle. Geophysics, 78(3), J33–J41.
Gaál, G., Berthelsen, A., Gorbatschev, R., Kesola, R., Lehtonen, M. I., Marker, M., et al. (1989). Structure and composition of the Precambrian crust along the POLAR Profile in the northern Baltic Shield. Tectonophysics, 162(1–2), 1–25.
Hsu, S. K., Sibuet, J. C., & Shyu, C. T. (1996). High-resolution detection of geologic boundaries from potential-field anomalies: An enhanced analytic signal technique. Geophysics, 61(2), 373–386.
Koistinen, T., Stephens, M. B., Bogatchev, V., Nordgulen, Ø., Wennerström, M., Korhonen, J. (2001). Geological map of the Fennoscandian Shield, scale 1:2 000 000. Trondheim: Geological Survey of Norway, Uppsala: Geological Survey of Sweden, Moscow: Ministry of Natural Resources of Russia, Espoo: Geological Survey of Finland.
Li, L., Ma, G., & Du, X. (2012). Edge detection in potential-field data by enhanced mathematical morphology filter. Pure and Applied Geophysics, 170(4), 645–653.
Ma, G. (2013). Edge detection of potential field data using improved local phase filter. Exploration Geophysics, 44(1), 36–41.
Ma, G., Liu, C., & Li, L. (2014). Balanced horizontal derivative of potential field data to recognize the edges and estimate location parameters of the source. Journal of Applied Geophysics, 108, 12–18.
Miller, H. G., & Singh, V. (1994). Potential field tilt—a new concept for location of potential field sources. Journal of Applied Geophysics, 32(2–3), 213–217.
Nabighian, M. N. (1972). The analytic signal of two-dimensional magnetic bodies with polygonal cross-section: Its properties and use for automated anomaly interpretation. Geophysics, 37(3), 507–517.
Nasuti, A., Roberts, D., Dumais, M. A., Ofstad, F., Hyvönen, E., Stampolidis, A., et al. (2015a). New high-resolution aeromagnetic and radiometric surveys in Finnmark and North Troms: linking anomaly patterns to bedrock geology and structure. Norwegian Journal of Geology, 95, 217–243.
Nasuti, A., Roberts, D., & Gernigon, L. (2015b). Multiphase mafic dykes in the Caledonides of northern Finnmark revealed by a new high-resolution aeromagnetic dataset. Norwegian Journal of Geology, 95, 285–297.
Novatem. (2012). Fixed wing magnetic and radiometric survey of the coastal area of Northwestern Norway (FRAS–E). Report no. C11089, Novatem Airborne Geophysics, Mont-Saint Hilaire, 36.
Novatem. (2014). Fixed wing magnetic and radiometric survey over the Troms-Finnmark region in Northern Norway (TROFI-14 E). Report no. C14104, Novatem Airborne Geophysics, Mont-Saint Hilaire, Quebec, Canada, 29.
Olesen, O., & Sandstad, J. S. (1993). Interpretation of the Proterozoic Kautokeino Greenstone Belt, Finnmark, Norway from combined geophysical and geological data. Norges geologiske undersøkelse Bulletin, 425, 43–64.
Roest, W. R., Verhoef, J., & Pilkington, M. (1992). Magnetic interpretation using the 3-D analytic signal. Geophysics, 57(1), 116–125.
Verduzco, B., Fairhead, J. D., Green, C. M., & MacKenzie, C. (2004). New insights into magnetic derivatives for structural mapping. The Leading Edge, 23(2), 116–119.
Wijns, C., Perez, C., & Kowalczyk, P. (2005). Theta map: edge detection in magnetic data. Geophysics, 70(4), 39–43.
Acknowledgements
We are grateful to Christine Fischer and Julia Curto for constructive reviews that have greatly improved the manuscript. We also thank David Roberts for his comments and also help with improving the English language of the manuscript.
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Nasuti, Y., Nasuti, A. & Moghadas, D. STDR: A Novel Approach for Enhancing and Edge Detection of Potential Field Data. Pure Appl. Geophys. 176, 827–841 (2019). https://doi.org/10.1007/s00024-018-2016-5
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DOI: https://doi.org/10.1007/s00024-018-2016-5