Tectonophysical Approach to the Analysis of Geological and Geophysical Data at the Kovykta Gas-condensate Field

Summary In the report the results of application of modern ways in the tectonophysical analysis of geological and geophysical data for identification of regularities in a fault structure of a platform cover on the Kovykta gascondensate field (GCF) are considered. The basis for research of sedimentary cover are the materials of 3D seismic and electromagnetic survey, the structural data and materials of digital relief model processing. As a result of the complex analysis the zone-block structure (ZBS) of the Kovykta GCF is established. It represents hierarchy of blocks which contact with each other on wide zones of short fractures concentration. The ZBS style is defined by domination of subhorizontal fault zones (layer-by-layer stripping) and subvertical zones of northwest and northeast orientations. The network of the fault zones was formed in four stress fields which correspond with the main stages of an adjacent Baykal- Stanovoy mobile belt development in the Paleozoic- Cenozoic. Some fields are reactivated in the Cenozoic under the influence of the gravitational processes connected with local lifted raisings of a relief. The zone-block structure of the Kovykta GCF is a basis for it's zonation on hydrocarbon productivity, overpressure zones, on degree of fracturing and types of stress state of rocks. The solution of this task will allow to receive additional substantiating for the choice of drilling site which can be passed without geohazards and with the prospect of detection of natural gas accumulation.