Astrakhan Oblast, Russia. The Caspian Depression. 3D localisation of heterogeneous zones in a vertical section for drilling accidents prevention.
Technological task; depth of investigation: 0-4000m
The LFS method can also be used in technological problem solving. This particular challenge was to identify heterogeneous zones in a vertical section located above an identified condensate pool in order to minimise complications during the drilling of productive wells and avoid accidents.
Due to the presence of developed salt-dome tectonics, the LFS studies were carried out using 3D-numerical modelling, which allowed the prediction of the presence of inhomogeneities above the main productive horizon. Heterogeneity was understood to be the presence of zones of decompaction, layers with abnormally high reservoir pressure and natural or technogenic hydrocarbon deposits.
The obtained results were analysed jointly with the customer, involving data on complications in the drilling process in the wells already drilled. The analysis showed good coincidence of the heterogeneities identified by the LFS method with the intervals of complications in the wells.