Regional gravity and magnetic anomalies are interpreted with regard to new geodynamic, geological, and tectonic schemes. Integrated analysis of these data confirms the deep origin of the processes which have created the largest igneous areas and zones of the eastern Central Asian Fold Belt.

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The role of fracture and faulting zones in the filtration inhomogeneity of productive formations in oil and gas fields has been considered. The absence of fracture or faulting zones from geological and, consequently, hydrodynamical models reduces the flooding efficiency and the oil recovery factor in general. The current situation results from the underdevelopment of methods for the mapping and classification of fracture zones based on seismic-prospecting data. For example, the use of the seismic-horizon gradient method makes it possible to describe only complete rock fracturing at tectonic-block boundaries. We propose to use the structural inhomogeneity of the deformation field of seismic horizons for a more complete description and classification of fracture zones by the faulting regime. This parameter is suitable not only for late but also for early stages of faulting and describes block-boundary deformations more accurately than gradients. The example of a West Siberian oil and gas field showed that the production wells from the J1 productive formation in the faulting zones with the calculated post-Cenomanian structural inhomogeneity of the deformation field have considerably higher discharges owing to fracture permeability.

––The use of satellite-geological information permits generalization of studies of various active geologic processes in a new way. As reference examples, we consider geologic regions extensively covered by research with our contribution. The joint use of satellite images, maps of gravity anomalies, and seismic-tomography data for Kamchatka made it possible to construct 3D models of surficial and deep-seated (depths from 10–50 to 650 km) volcanic structures. For young volcanosedimentary structures of Kamchatka, it is possible to trace the interaction of various processes, from crystallization of magmas in magma chambers to ore and oil formation in calderas. Ancient tectonic structures and superposed Cenozoic deformations in the Tien Shan, Altai, and Baikal regions are clearly displayed in satellite images and on maps of gravity anomalies. The long-range impact of the Indo-Eurasian collision on the Tien Shan, Altai, and Baikal regions was expressed as shearing, which resulted in the most contrasting structures in the zones of junction of regional faults and along the framing of cratonal structures. The active structures of Gorny Altai contain numerous travertines, whose abundance is correlated with seismic activity. The mass formation of methane and gas hydrates in Lake Baikal might be related to mantle plume fluids.

The present paper considers certain problems of gravity monitoring at oil and gas fields arising due to inversion of repeat measurement data, when finding the positions of water–oil and water–gas contacts. The main sources of noise in gravity data are errors in vertical positioning of the tool, changes in atmospheric pressure, and variations in groundwater level and soil moisture. An algorithm based on using a multisensor borehole tool is proposed for a more accurate inversion. Examples of locating successfully the water front while solving model problems with the help of this algorithm are provided.