Use of data of satellite system for gravity recovery and climate experiment (GRACE) for studying and assessment of hydrological-geohydrological characteristics of large river basins

Analysis is given of a relatively new method for studying the distribution and dynamics of land water resources, which is based on measuring the anomalies of Earth gravity field with the use of GRACE satellite system. The international satellite experiment on determining the gravity and climate changes has been carried out since 2002 with the aim of making high-frequency (within the frequency range of 10900?C36000 GHz) measurements of time variations in Earth??s gravity field. The measurement method and the procedure of data processing and evaluating the hydrological-geohydrological characteristics of large river basins and regions based on GRACE data.     

The accuracy of determining the effective layer density at gravity logging

This paper discusses the basic kinds of uncertainties arising in gravity logging. It shows how the accuracy of density determination depends on accuracy in depth determinations, as well as in reference and routine surveying. Corrections to be used in borehole surveying are listed. Field results from gravity and gamma- gamma density logging are reported.     

Potential field transformation on the basis of a continuous wavelet transform

The possibility of applying the continuous wavelet analysis on the basis of a Poissonian core for the processing and interpretation of gravity and magnetic survey data is considered. Based on the wavelet spectrum, W(x,h), reconstruction of the initial signal, g(x), is possible. Additionally, based on this wavelet spectrum, the equivalent distributions of mass and magnetization that produce the initial field, g(x), can be reconstructed. These possibilities allow the wavelet transform to be used for solving such classical problems as the filtering of initial signals, continuation of the field, calculation of higher field derivatives in the upper and lower half-spaces, and reduction of magnetic anomalies to the pole.     

The Field of Attraction of a Polyhedron and Polygonal Plate with Linear Density

New representations of the elements of the fields of attraction (potential and its first derivatives) are presented for the important approximating models such as polyhedron and polygonal plates with the density varying by the linear law. It is shown that these elements are determined through the elements of the fields from the models with the known analytical representations (polyhedron, polygonal plate, and material segment with constant densities) and the additional integrals for which the explicit analytical expressions exist.     

The results of gravity surveys at geophysical grounds in the Kaluga region

The scientific educational practice on gravimetry for the second-year students of the geophysical specialty in 2012–2013 was executed in Central Russia (Kaluga region, the Village of Aleksandrovka). It allowed us to provide an educational process with modern high-precision gravimeters and to fully preserve the curricula and to add elements of topography and geodesic practice. Over these 2 years reliable facts and data were received, which illustrated the possibilities of high-precision gravity measurements in studying the sedimentary cover features of a geological structure.     

Numerical simulation of thermoremanent magnetization in intrusions

This paper is devoted to the possibility of inverse remanent magnetization that is acquired in intrusive rocks due to a magnetic field that is produced by a sum of the normal core field and an anomalous effect induced by solidified rocks. A computer program has been created to simulate the process of solidification of intrusive body rocks from its edges to the center. The computing results showed the possibility of remanent magnetization that is acquired, which can have a different direction as compared to the external magnetic field, up to the inverse one.     

A Projection Method for Solving Systems of Linear Equations: Gravimetry Applications

Doklady Earth Sciences - Existing methods for solving inverse problems, such as the regularization method, look mostly for a quasi-solution that may not be a solution to the original problem, but...     

Two-dimensional gravity simulation of the tectonosphere under the American-Antarctic Ridge

This paper discusses the results of a two-dimensional gravity simulation along a number of transects across the American-Antarctic Spreading System. Bathymetric data, as well as the data of gravity anomalies from satellite altimetry and data on the age of the ocean floor, were used as data. The results of a preliminary three-dimensional simulation were applied for constructing the model and for analyzing the field of complete normalized gradient. A qualitative analysis of the principal tectonosphere boundaries in individual segments of the American-Antarctic Spreading System was undertaken.     

The structure of the Falkland Basin’s lithosphere

The peculiarities of the crustal structure within the Falkland Basin have been discussed. Maps of the free-air and Bouguer (2.3 g/cm³) gravity anomalies and their transforms have been made. The complex analysis of the anomalous gravity field has allowed us to confirm the continental origin of the crust. The zoning of the crust has been performed. The crust is thinned and is enriched in basic and ultrabasic intrusions. A map demonstrating the distribution of the faults within the studied water area has been made. A conclusion has been reached about the leading role played by tension processes throughout the evolution of the crust within the studied water area.     

The structure of the heterogeneous basement of the Krasnoleninsky arch and adjacent territories (West Siberia) according to the analysis of gravitational and magnetic fields

In this work a scheme of the gravitational and magnetic fields is represented that allows us to distinguish blocks in the basement of the studied region that are homogeneously manifested in the potential fields. Two approaches are considered: the qualitative (contact) approach and the regionalization approach using a classification algorithm. Both approaches give similar results. The association of hydrocarbon fields opened in the Pre-Jurassic sediments to the boundaries of the tectonic blocks we distinguished is noted.