Abstract
Fourier transformation of gravity and magnetic anomalies from space to the frequency domain provides aready method for source depth estimation since progressively deeper sources are indicated by the lower frequency components of an anomaly. Two examples are presented here to demonstrate the efficacy of this approach. One example pertains to the interpretation of vertical intensity magnetic anomalies over a layered ultramafic body for estimating the thickness of relatively non-magnetic layer in it and map the dispositions of the layers. The other example is the estimation of crustal thickness in the Indian region from the Bouguer anomaly map. The spectral method is shown, by these two examples, to provide a rapid and elegant tool for the source depth estimation for magnetic and gravity data.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Avasthi, D. N. andSatyanarayana, M. (1970),Inferences regarding the Upper Mantle from the gravity data in Punjab and Ganges plains, Proc. II U.M.P. Symp. Hyderabad, pp. 25–38.
Bath, M.,Spectral Analysis in Geophysics (Elsevier, 1974) 563 pp.
Bhattacharyya, B. K. (1966),Continuous spectrum of total magnetic field anomaly due to a rectangular prismatic body, Geophys.31, 97–121.
Choubey, B. D. (1971),Narmada-Son Lineament, India, Nature Phys. Sci.232, 38–40.
Dean, W. C. (1958),Frequency analysis for gravity and magnetic interpretation, Geophys.23, 97–127.
Green, A. G. (1972),Magnetic profile analysis, Geophys. J. Roy. Astr. Soc. Lond.30, 393–403.
Gudmundsson, O. (1966),Interpretation of one-dimensional magnetic anomalies by use of Fourier Transform, Geophys. J. Roy. Astr. Soc. Lond.12, 87–97.
Hahn, A., Kind, E. andMishra, D. C. (1976),Depth estimation of magnetic sources by means of Fourier amplitude spectra, Geophy. Prosp.24, 287–308.
Heiskanen, W. A. andMeinesz, F. A. V.,The Earth and its Gravity Field (McGraw-Hill, 1958), 470 pp.
Kanasewich, E. R.,Time Sequence Analysis in Geophysics (University of Alberta Press, 1975), 364 pp.
Mishra, D. C. (1977),Possible extensions of the Narmada-Son Lineament towards Murrey Ridge (Arabian Sea) and the Eastern Syntaxial Bend of the Himalayas, Earth Planet. Sci. Lett.36, 301–308.
Naidu, P. S. (1970a),Fourier Transform of large scale aeromagnetic field using a modified version of Fast Fourier Transform, Pure appl. Geophys.81, 17–25.
Naidu, P. S. (1970b),Statistical structure of aeromagnetic field, Geophys.35, 279–292.
Naqvi, S. M., Divakara Rao, V. andNarain, H. (1974),The protocontinental growth of the Indian shield and the antiquity of its rift valleys, Precambrian Res.1, 345–398.
Neidell, N. S. (1965),A geophysical application of spectral analysis, Appl. Statistics(Roy. Stat. Soc.), C 14, 75–88.
Pal, P. C. andBhimasankaram, V. L. S. (1976),Tectonics of the Narmada-Son-Brahmaputra Lineament, Misc. Publn.34, Geol. Surv. Ind., pp. 133–140.
Pal, P. C. andSreenivas, G. (1976),The Narmada-Son Lineament, Geophys. Res. Bull.14, 1–7.
Pal, P. C., Rao, B. N. andUnnikrishnan, P.,Asbestos Exploration in Roro—A Prospective Strategy (Osmania University Press, 1977), 90 pp.
Peters, L. J. (1949),The direct approach to magnetic interpretation and its practical application, Geophys.14, 290–320.
Qureshy, M. N., Aravamadhu, P. S. andBhatia, S. C. (1967),Some regional gravity traverses through India, Proc. U.M.P. Symp., Hyderabad, pp. 120–133.
Qureshy, M. N. (1970),Relation of gravity to elevation, geology and tectonics of India, Proc. II U.M.P. Symp. Hyderabad, pp. 1–23.
Regan, R. D. andHinze, W. J. (1976),The effect of finite data length in the spectral analysis of ideal gravity anomalies, Geophys.41, 44–55.
Roy, A. (1966),The method of continuation in mining geophysical interpretation, Geoexploration4, 65–84.
Roy, A. (1967),Convergence in downward continuation for some simple geometries, Geophys.32, 853–866.
Saha, A. K. (1970),The present status of the Precambrian geology of the Singhbhum region, Proc. II U.M.P. Symp. Hyderabad, pp. 259–278.
Sazhina, N. andGrushinsky, Y.,Gravity Prospecting (Mir Publishers, 1971), 491 pp.
Spector, A. andGrant, F. S. (1970),Statistical methods for interpreting aeromagnetic data, Geophys.35, 293–302.
Trettel, S., Clement, W. G. andKaul, R. K. (1971),The spectral determination of depths to buried magnetic basement rocks, Geophys. J. Roy. Astr. Soc. Lond.24, 415–428.
Vyskoch, V. andKoziskov, M. (1966),Korrelation zwischen den Schwereanomalien und Seehöhen in Mitteleuropa, Travaux de l'Institut Geophysique de l'Academie Tchescoslovaque des Sciences; Geofysikalni sbornik252, 75–80.
Woollard, G. P. (1959),Crustal structure from gravity and seismic measurements, J. Geophys. Res.64, 1524–1544.
Woollard, G. P. (1968),The interrelationship of the crust, the upper mantle and the isostatic gravity anomalies in the United States, inThe Crust and Upper Mantle of the Pacific Area (Ed. C. L. Drake and P. J. Hart), (A.G.U. Monograph 12, 1968), pp. 312–341.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Pal, P.C., Khurana, K.K. & Unnikrishnan, P. Two examples of spectral approach to source depth estimation in gravity and magnetics. PAGEOPH 117, 772–783 (1978). https://doi.org/10.1007/BF00879978
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00879978