Abstract
Downward continuation of the potential data (gravity or magnetic) helps to interpret contributing sources by transforming the physical signal to their neighborhood. This paper applies three continuation approaches (Landweber’s iteration, the direct method and the inverse-matrix approach with Tikhonov’s regularization), based on the Poisson integral equation, and four integration schemes to the second vertical derivative of the anomalous potential \(T_{\rm zz}\) obtained from GOCE data. In the experiments, \(T_{\rm zz}\) was downward continued for 250 km in the area of Central Europe with special attention to edge effects. For the integration schemes, which use prior information outside the region of interest to reduce edge effects, the best agreement with TIM-r4 was achieved by the inverse-matrix approach with Tikhonov’s regularization (RMS = 1.15 eotvos). On the contrary, without prior information the iterative approach performed with RMS = 1.17 eotvos.
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Notes
\(T\) is obtained from \(V\) by subtracting some reference field; we have used GRS80 up to degree 10 (Moritz 1980).
Poisson integral can rigorously be applied to z-derivative of any order in the local frame as long as the term \((R/r)^{i}\) with positive integers \(i\) is constant for two concentric spheres (input and output altitudes), see, e.g., discussion in Hotine (1969, p. 316).
References
Arfken GB, Weber HJ (2005) Mathematical methods for physicists, 6th edn. Academic Press, London
Elysseieva I, Pašteka R (2009) Direct interpretation of 2D potential fields for deep structures by means of the quasi-singular points method. Geophys Prospect 57(4):683–705
ESA (1999) Gravity field and steady-state ocean circulation. Reports for mission selection—the four candidate Earth Explorer core missions. ESA publication division, SP-1233(1)
Eshagh M (2011) Inversion of satelite gradiometry data using statistically modified integral formulas for local gravity field recovery. Adv Space Res 47:74–85
Fedi M, Florio G (2002) A stable downward continuation by using the ISVD method. Geophys J Int 151(1):146–156
Fedi M, Florio G (2011) Normalized downward continuation of potential fields within the quasi-harmonic region. Geophys Prospect 59(6):1087–1100
Gruber T, Rummel R, Abrikosov O, van Hees R (2010) Goce level 2 product data handbook. Technical report, GO-MA-HPF-GS-0110
Haagmans R, de Min E, van Gelderen M (1993) Fast evaluation of convolution integrals on the sphere using 1-D FFT, and a comparison with existing methods for Stokes’ integral. Manuscr Geod 18:227–241
Hansen P, O’FLeary DP (1993) The use of the L-curve in the regularization of discrete ill-posed problems. SIAM J Sci Comput 14:1487–1503
Hansen PC (2007) Regularization tools version 4.0 for matlab 7.3. Numer Algorithms 46(2):189–194
Hees VS (1990) Stokes formula using FFT techniques. Manuscr Geod 15:235–239
Heiskanen WA, Moritz H (1967) Physical geodesy. W. H. Freeman, San Francisco
Hotine M (1969) Mathematical geodesy. Washington DC, U.S. Department of Commerce
Huestis SP, Parker RL (1979) Upward and downward continuation as inverse problems. Geophys J R Astron Soc 57(1):171–188
Janák J, Fukuda Y, Xu P (2009) Application of GOCE data for regional gravity field modeling. Earth Planets Space 61(7):835–843
Janák J, Pitoňák M, Minarechová Z (2014) Regional quasigeoid from GOCE and terrestrial measurements. Stud Geophys Geod 58(4):626–649
Jekeli C (2007) 3.02—potential theory and static gravity field of the Earth. In: Schubert G (ed) Treatise on geophysics. Elsevier, Amsterdam, pp 11–42
Kellogg OD (1929) Foundation of potential theory. Frederick Ungar, New York
Kern M (2003) An analysis of the combination and downward continuation of satellite, airborne and terrestrial gravity data. University of Calgary, Calgary
King JT, Chillingworth D (1979) Approximation of generalized inverses by iterated regularization. Numer Funct Anal Optim 1(5):499–513
Landweber L (1951) An iteration formula for Fredholm integral equations of the first kind. Am J Math 73:615–624
Lee JB (2001) FALCON gravity gradiometer technology. Explor Geophys 32(3/4):247–250
Li Y, Devriese S et al (2009) Enhancement of magnetic data by stable downward continuation for uxo applications. In: International exposition and annual meeting, SEG Houston, pp 1464–1468
Ma T, Chen L, Wu Z, Hu X, Wu M (2012) An improved iteration method for downward continuation of potential fields. In: 2nd international conference on industrial technology and management (ICITM 2012), Phuket Island, Thailand
Miller K (1970) Least squares methods for ill-posed problems with a prescribed bound. SIAM J Math Anal 1(1):52–74
Moritz H (1980) Geodetic reference system 1980. J Geod 54(3):395–405
Novák P, Heck B (2002) Downward continuation and geoid determination based on band-limited airborne gravity data. J Geod 76(5):269–278
Novák P, Kern M, Schwarz K-P (2001) Numerical studies on the harmonic downward continuation of band-limited airborne gravity. Stud Geophys Geod 45(4):327–345
Oldenburg D (1974) The inversion and interpretation of gravity anomalies. Geophysics 39(4):526–536
Pail R, Bruinsma S, Migliaccio F, Foerste C, Goiginger H, Schuh W-D, Hoeck E, Reguzzoni M, Brockmann J, Abrikosov O, Veicherts M, Fecher T, Mayrhofer R, Krasbutter I, Sans F, Tscherning C (2011) First GOCE gravity field models derived by three different approaches. J Geod 85(11):819–843
Parker RL (1973) The rapid calculation of potential anomalies. Geophys J R Astron Soc 31(4):447–455
Pašteka R, Karcol R, Kušnirák D, Mojzeš A (2012) REGCONT: a matlab based program for stable downward continuation of geophysical potential fields using tikhonov regularization. Comput Geosci 49:278–289
Pavlis NK, Holmes SA, Kenyon SC, Factor JK (2012) The development and evaluation of the earth gravitational model 2008 (EGM2008). J Geophys Res (Solid Earth) 117(B16):4406
Phillips J (1996) Potential-field continuation: past practice vs. modern methods. In: SEG annual meeting, Denver, CO. Society of Exploration Geophysicists
Pick M, Vyskočil V, Pícha J (1973) Theory of the earth’s gravity field. Elsevier Scientific, New York
Press WH (1996) Numerical recipes in FORTRAN 77 and FORTRAN 90 the art of scientific and parallel computing. Cambridge University Press, Cambridge
Schmidt P, Clark D, Leslie K, Bick M, Tilbrook D, Foley C (2004) Getmaga squid magnetic tensor gradiometer for mineral and oil exploration. Explor Geophys 35(4):297–305
Sebera J, Šprlák M, Novák P, Bezděk A, Vaľko M (2014) Iterative spherical downward continuation applied to magnetic and gravitational data from satellite. Surv Geophys 35(4):941–958
Shen Y, Xu P, Li B (2012) Bias-corrected regularized solution to inverse ill-posed models. J Geod 86(8):597–608
Šprlák M, Sebera J, Vaľko M, Novák P (2014) Spherical integral formulas for upward/downward continuation of gravitational gradients onto gravitational gradients. J Geod 88(2):179–197
The MathWorks (2011) MATLAB version R2011a. The MathWorks, Inc., Natick, Massachusetts, United States
Tikhonov AN (1963a) Solution of incorrectly formulated problems and the regularization method. Sov Math Dokl 5:1035–1038
Tikhonov AN (1963b) Regularization of incorrectly posed problems. Sovi Math Dokl 4:1624–1627
Wahba G (1990) Spline models for observational data, vol 59. SIAM, Philadelphia, PA
Xu P (1992) Determination of surface gravity anomalies using gradiometric observables. Geophys J Int 110(2):321–332
Xu P, Fukuda Y, Liu Y (2006a) Multiple parameter regularization: numerical solutions and applications to determination of geopotential from precise satelite orbits. J Geod 80:17–27
Xu P, Shen YZ, Fukuda Y, Liu Y (2006b) Variance components estimation in linear inverse ill-posed models. J Geod 80:69–81
Xu S-Z, Yang J, Yang C, Xiao P, Chen S, Guo Z (2007) The iteration method for downward continuation of a potential field from a horizontal plane. Geophys Prospect 55(6):883–889
Zeng X, Li X, Su J, Liu D, Zou H (2013) An adaptive iterative method for downward continuation of potential-field data from a horizontal plane. Geophysics 78(4):J43–J52
Zhang H, Ravat D, Hu X (2013) An improved and stable downward continuation of potential field data: the truncated taylor series iterative downward continuation method. Geophysics 78(5):J75–J86
Acknowledgments
Josef Sebera has been supported by the project EXLIZ—CZ.1.07/2.3.00/30.0013, Martin Pitoňák and Eliška Hamáčková were supported by the project CZ.1.05/1.1.00/02.0090 NTIS—New Technologies for the Information Society. Martin Pitoňák has been supported by the national project APVV-0072-11. We thank Prof. M. Fedi, an anonymous reviewer and an Associate Editor for constructive discussion that helped us to improve the manuscript.
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Sebera, J., Pitoňák, M., Hamáčková, E. et al. Comparative Study of the Spherical Downward Continuation. Surv Geophys 36, 253–267 (2015). https://doi.org/10.1007/s10712-014-9312-0
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DOI: https://doi.org/10.1007/s10712-014-9312-0