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  • 1.
    Chapellier, D.
    et al.
    Lausanne, United States.
    Fitterman, D.
    Denver, CO, United States.
    de Stadelhofen, C. Meyer
    Lausanne, United States.
    Parasnis, D. S.
    Luleå tekniska universitet.
    Steeples, D. W.
    Lawrence, KS, United States.
    Valla, P.
    Orléans, United States.
    Preface1994Inngår i: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 31, nr 1-4, s. 7-Artikkel i tidsskrift (Annet vitenskapelig)
  • 2.
    Das, U.C.
    et al.
    Koninklijke/Shell, Exploratie en Produktie Lab., Rijswijk, The Netherlands.
    Parasnis, Dattatray
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Resistivity and induced polarization responses of arbitarily shaped 3-D bodies in a two-layered Earth1987Inngår i: Geophysical Prospecting, ISSN 0016-8025, E-ISSN 1365-2478, Vol. 35, nr 1, s. 98-109Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Numerical computations using the integral equation method are presented for resistivity and IP responses due to arbitrarily shaped 3‐dimensional bodies in a layered earth. The unknown surface charge density distribution is expressed as the solution of Fredholm's integral equation of the second kind. Use of moment method (with pulse basis function and point‐collocation) yields the matrix equations for the unknowns. The contributions to Green's function are solved (a) analytically for the primary and (b) by convolution for the secondary contributions resulting in a fast algorithm. The further step of computing potential, apparent resistivity, chargeability etc., for any electrode system, is straightforward. Our results show a good agreement with those from finite difference methods and physical tank experiments. The CPU time is only 138 s on a super‐minicomputer for an apparent resistivity pseudo‐section, even with 96 elementary cells as used for discretization. A large number of models for different geological situations were studied; some are presented here.

  • 3.
    Parasnis, Dattatray
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Geothermal work at the University of Luleå, Sweden in relation to EGT11985Inngår i: Terra Cognita, Vol. 5, nr 4, s. 398-Artikkel i tidsskrift (Annet vitenskapelig)
  • 4. Parasnis, Dattatray
    Magnetism: from lodestone to polar wandering1961Bok (Annet vitenskapelig)
  • 5.
    Parasnis, Dattatray
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Mining geophysics1973 (oppl. 2 rev.)Bok (Annet vitenskapelig)
  • 6.
    Parasnis, Dattatray
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    More comments on "A theorem for DC regimes and some of its consequences" by A. Roy1984Inngår i: Geophysical Prospecting, ISSN 0016-8025, E-ISSN 1365-2478, Vol. 32, nr 1, s. 139-141Artikkel i tidsskrift (Annet vitenskapelig)
  • 7.
    Parasnis, Dattatray
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Principles of applied geophysics1997 (oppl. 5)Bok (Annet vitenskapelig)
  • 8.
    Parasnis, Dattatray
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Principles of applied geophysics1986 (oppl. 4)Bok (Annet vitenskapelig)
    Abstract [en]

    Anyone who compares the present thoroughly revised and enlarged edition of this book with the three previous ones, the first of which was published in 1962, may well ask whether the principles of applied geophysics have become more numerous during the last 25 years or so. Such is not the case and the much larger size of the present edition is due to the principles' having been explained in greater detail than heretofore. There are major and minor alterations, additions and emendations, too numerous to be listed here, throughout the book but I would like to draw attention specifically to some of them. The chapter on seismic methods is now far more extensive than before and so are also the chapters on electric and electromagnetic methods. There is also a separate chapter on well logging in oil fields giving the essential ideas. Considering the virtual plethora of available books on seismic methods and on well logging I have not thought it necessary to extend these chapters further. This has enabled me to keep the book to a reasonable length and at the same time retain its fairly comprehensive character. Other features of the present edition are solved examples in the text and the problems at the end of all principal chapters. Answers and hints to the latter are given at the end of the book.

  • 9.
    Parasnis, Dattatray
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Reciprocity theorems in geoelectric and geoelectromagnetic work1988Inngår i: Geoexploration, ISSN 0016-7142, Vol. 25, nr 3, s. 177-198Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The following two theorems are proved and discussed: 1. (1) the open-circuit potential difference between two electrodes M,N when steady current is passing through electrodes A,B is equal to that between A and B if the same current is passed through M,N for any arbitrary conductivity distribution in the ground provided only the ground is a linear medium;2. (2) the complex electromotive force developed in a receiver circuit R of small dimensions, due to alternating current flowing in a transmitter circuit T of small dimensions is exactly equal to the complex e.m.f. in T if the same current is flowing in circuit R, no matter how arbitrary the distribution of conductivity, magnetic permeability and dielectric permittivity in the ground, provided only the ground is a linear medium.A linear medium is one in which the current density, magnetic flux density and electric displacement are linear functions of electric and magnetic field intensities. The more general form of the second theorem when the dimensions of the circuits are not small is proved first and the special case of (2) derived from it.

  • 10.
    Parasnis, Dattatray
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Temperature phenomena and heat flow estimates in two precambrian ore-bearing areas in north Sweden1975Inngår i: Geophysical Journal International, ISSN 0956-540X, E-ISSN 1365-246X, Vol. 43, nr 2, s. 531-554Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Temperature measurements in 17 drillholes reaching vertical depths between 365 and 780 m below ground surface in the Skellefte area (lat. 65° 52deg;N, long. 20° 20° E Gr) and Aitik area (lat. 67° 5deg;N, long. 21° E Gr) in the Swedish precambrian are reported. The absolute accuracy of the measurements was about 0.03°C and the relative one about 0.005°C. A large number of thermal diffusivity measurements were made on rock samples from the two areas in order to estimate the correction to the observed steady geothermal gradients due to climatic amelioration at the end of the Pleistocene. The corrected gradients are between 0.01266°C m-1 and 0.01485°C m-1 (Skellefte) and between 0.01684°C m-1 and 0.02268°C m-1 (Aitik). The diffusivity measurements were supplemented by thermal conductivity determinations on 265 drillcore samples from the different rock formations in the holes.

    The undisturbed heat flow in the Skellefte area is found to be 48.7 mW m-2 and that in the Aitik area to be 49.8 mW m-2. Distortion of the heat flow due to a sulphide ore in the Skellefte area is demonstrated. The heat flow through the Långsele ore in this area is of the order of 70 mW m-2.

  • 11.
    Parasnis, Dattatray
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    The geophysics of fracture zones in hard-rock areas1981Inngår i: Second biennial conference and exhibition, 1981, s. 78-Konferansepaper (Annet vitenskapelig)
  • 12.
    Parasnis, Dattatray S.
    Luleå tekniska universitet.
    Comments on ‘Geophysical detection of mineral conductors in tropical terrains with target conductors partly embedded in the conductive overburden’ by J. O. Barongo1988Inngår i: Geophysical Prospecting, ISSN 0016-8025, E-ISSN 1365-2478, Vol. 36, nr 1, s. 92-93Artikkel i tidsskrift (Annet vitenskapelig)
  • 13.
    Parasnis, Dattatray S.
    Luleå tekniska universitet.
    Effect of a uniform overburden on the passage of a thermal wave and the temperatures in the undelying rock1976Inngår i: Geophysical Journal International, ISSN 0956-540X, E-ISSN 1365-246X, Vol. 46, nr 1, s. 189-192Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The system is a uniform overburden of thickness h, thermal The system considered k1, and diffusivity α1 overlying a semi‐infinite substratum (conductivity K2, diffusivity α2). It is shown that if the temperature of the surface varies with time t as T0 sin ωt, the temperatures v1, v2 in the overburden and the substratum respectively are given by: (Formula Presented.) The apparently simple boundary value problem has thus a surprisingly involved solution. The solution is of considerable importance in shallow geothermal measurements in, for example, moraine‐covered areas such as the Swedish Precambrian or in areas of uniform in situ weathering.

  • 14.
    Parasnis, Dattatray S.
    Luleå tekniska universitet.
    Geothermal flow and phenomena in two Swedish localities north of the Arctic circle1982Inngår i: Geophysical Journal International, ISSN 0956-540X, E-ISSN 1365-246X, Vol. 71, nr 3, s. 545-554Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Temperature measurements in eight holes reaching vertical depths between 287 and 1100m below ground surface in the Malmberget area (lat. 67° 10' N, long. 20° 40' E Gr.) and the Kiruna area (lat. 67° 52' N, long. 20° 9' E Gr.) in the Swedish Precambrian are reported. The mean equilibrium heat flow in this part of the Swedish shield after climatic correction is 52.6 ± 1.7mWm-2. The mean uncorrected heat flow is 46.6 mWm-2. Comparison with other shield areas shows that in common with the S. African and Indian shields, the north Swedish shield has a greater heat flow than the remaining shield areas of the world.

  • 15.
    Parasnis, Dattatray S.
    Luleå tekniska universitet.
    PhD theses1988Inngår i: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 333, nr 6171, s. 294-Artikkel i tidsskrift (Annet vitenskapelig)
  • 16.
    Parasnis, Dattatray S.
    et al.
    Luleå tekniska universitet.
    Elming, Sten-Åke
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    The non-magnetic house of the University of Luleå, Sweden1982Inngår i: Geologiska Föreningen i Stockholm Förhandlingar, ISSN 0016-786X, Vol. 104, nr 2, s. 186-188Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The building of a very quiet non-magnetic house can raise special problems in Precambrian areas and in the cold climate of northern Sweden. The special precautions taken in the construction of a non-magnetic house belonging to the University of Lule have resulted in a laboratory for high-precision rock magnetic and palaeomagnetic work. The mean total field in the house one metre above the floor is 52011 ±3 nT and the maximum variation inside is 12 nT. The geographical, position is the mountain Rånekölen, latitude 65.8°N, longitude 22.3°EGr, about 30 km north of Luleå.

  • 17.
    Seigel, Harold
    et al.
    Colorado School of Mines, Golden.
    Nabighian, Misac
    Colorado School of Mines, Boulder.
    Parasnis, Dattatray
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Vozoff, Keeva
    University of Sydney.
    The early history of the induced polarization method2007Inngår i: The Leading Edge, ISSN 1070-485X, E-ISSN 1938-3789, Vol. 26, nr 3, s. 312-321Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper traces the early development of the induced polarization method, starting with field observations by Conrad Schlumberger in a mining region in France, about 1913. Starting about 1929 he introduced this technique into hydrocarbon borehole logging in the USSR, and this resulted in further development in eastern and western Europe.

  • 18.
    Wyller, J.
    et al.
    Luleå tekniska universitet.
    Wellander, N.
    Luleå tekniska universitet.
    Larsson, F.
    Parasnis, Dattatray
    Burger's equation as a model for the IP phenomenon1992Inngår i: Geophysical Prospecting, ISSN 0016-8025, E-ISSN 1365-2478, Vol. 40, nr 3, s. 325-341Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The dynamic response characterizing the induced-polarization (IP) phenomenon is modelled by a nonlinear diffusion equation (Burger's equation) supplemented by relevant initial and boundary values. The analysis of the model yields a voltage step response and an impedance curve in the frequency domain which agree qualitatively with experimental measurements. Curve fits based on the model have been made in the case of electrochemical cell measurements. The diffusion coefficients estimated by means of these curves are of the same order of magnitude as those calculated using experimental measurements. The normalized transient with these diffusion coefficients agrees with observations, but probably has a shorter discharge time. We have also carried out a comparison with predictions obtained from a linear, finite diffusion layer model, thus showing that for most practical situations the nonlinear term modelling the migration effect can be neglected

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