Chayandinskoye field is the project of new technologies implementation in East Siberia

Modern level of study of structure of Chayandinskoye oil and gas condensate field is characterized by implementation of 3D seismic survey, carried out using a rich azimuth seismic survey system with a fold of 240. Complex seismic and geological conditions within this part of Eastern Siberia dictate high requirements to quality of field 3D seismic operations. A geological section of an area of operations is characterized by Lower Proterozoic formations of crystalline basement and Vendian, Cambrian, Jurassic, Quaternary deposits of the sedimentary cover. The main role in structure of the sedimentary cover is played by clastic and carbonate deposits of Vendian and halogen-carbonate formations of Cambrian Period. Productive part of a section refers to Botuobinsk, Khamakin and Talakh suits and is characterized by a very complex structure of natural reservoirs. Study of productive section structure is caused by need to prepare a field for production drilling and its subsequent development. In order to reveal features of structure of productive part of a section in a region with complex seismic and geological conditions, migration is used up to the summation in the deep region. Wide-azimuth observation system is aimed to study the most important challenges of medium structure such as direction and nature of change in fracture, study of azimuthal anisotropy of velocity characteristics of section and identification of characteristics of elastic properties change. Base technologies to study anisotropy of geological section properties are adapted and introduced into seismic exploration technique. They are as follows: 1) a method based on study of geometric attributes; 2) azimuthal analysis of velocities; 3) azimuth AVO-analysis (AVAZ); 4) anisotropic inversion. Based on results of processing and complex interpretation of seismic data of MOGT-3D works at the Chayandinskoye oil and gas condensate field the most important information about geological structure of sedimentary cover deposits and productive section was obtained. That allowed to significantly clarifying concept of structure of productive formations and geological development of this area. It also allowed determining distribution of reservoirs and evaluating reserves with considered new built structural and tectonic model.