(Summary) The functional conditions referring the anomalous potential have been worked out by the integral formula of Green. The value of the functionals over the continental areas has been calculated by the measured values of the gravity anomaly and the components of deflection of the vertical or of the geopotential number and for ocean areas by the measured values of the gravity disturbance or of the boundary values of the potential. The functional problem has been reduced to the restoration of the
finite-dimensional and unique geopotential which satisties the functional cxonditions best /in least-squares sense/. The discretisation of the functional could be carried out by means of a complete system of expansion unorthogonal functions. By the preliminary orthonormalization of this system the problem has been reduced to a system of linear equations, referring the coeficients of Fourier in the expansion of the potential. We propose four spherical solutions of the altimetry-gravimetry boundary problem by a discrete description and two in a closed form by a generalisation of the function of Stokes and Neumann /Hotine kernel/.
The dedicated satellite gravity missions have provided homogeneous and uniformly accurate information on the long and medium wavelengths of the Earth’s gravity field. Since the launch of GOCE satellite gravimetry mission by the European Space Agency (ESA) in 2009, several global geopotential models (GGMs) have been published. This study evaluates the recent GOCE-based GGMs over the area of Poland. The evaluation has been performed with the use of the EGM08 as well as high-precision GPS/levelling control traverse consisting of 184 stations. One GOCE-only GGM, four GOCE/GRACE satellite-only GGMs, and one GOCE/GRACE GGM combined with terrestrial gravity data have been selected for the evaluation. The results of inter-comparison of the models as well as their accuracy assessment have been discussed., Walyeldeen Godah and Jan Krynski., and Obsahuje bibliografii
Integration between magnetic and gravity data at the Zelten platform, the southeast part of Sirt Basin Libya. Zelten Platform is first discovered oil field in Libya. It shows numerous geological structures of different tectonic events. The methods adopted can assist in locating the hidden subsurface structures. The platform is characterized by the NW-SE trending rift that belongs to the Early Cretaceous age (during the collapse of Sirt Arch). The study aimed to define the structural geology that assisted in the development of future exploration in this area. The analyses utilized several filtering and transformation algorithms to help in structural modeling. For instance, the total horizontal gradient and tilt angle derivative were applied for the edge detection of the tectonic boundaries. The results show NW-SE and NNW-SSE patterns that represents faults that controlled the positions of the troughs and platforms at the Sirt basin. On the other hand, Euler deconvolution and 2D forward modeling were utilized to determine the depth of the basement. The Integrated models deduced revealed that the main faults trends are NW-SE which refer to the rift phases and crustal extension period that occurred during the Mesozoic time (early cretaceous). Also, the basement depth ranges from 6.5 km to 8 km according to the structures that affected the study area., Abdelhakim Eshanibli, Amin Khalil, Abdellatif Younis and Hussin Ghanoush., and Obsahuje bibliografii