METHOD OF DETECTING UNDERWATER DEPOSITS OF GAS HYDRATES

摘要

FIELD: physics.SUBSTANCE: disclosed is a method of detecting underwater deposits of gas hydrates, involving performing seismic low-frequency probing at frequencies 30-120 Hz with resolution of up to 12-24 m and high-frequency probing at frequencies ranging from 250-650 to 1200 Hz with resolution of 1-2 m. The obtained data are used to determine the lower and upper boundaries of hydrate-saturated rocks and hydrate concentration in the rocks, based on which gas resources are estimated and the site for drilling expendable wells for primary estimation of the deposit is selected. Detailed exploration of gas hydrate deposits is carried out via geophysical exploration in drilled wells. Seismic probing is further carried out at frequencies 0.001-30 Hz and the electromagnetic field is detected in the frequency range from 300 to 0.0001 Hz with detection period of 0.033 to 10000 s. Representative critical points of the relief surface between the lower and upper boundaries of the hydrate-saturated rocks are determined by detecting noise perturbations in the relief surface and comparing two relief surfaces with each other by constructing a Kronrod-Rib tree.EFFECT: high reliability of searching for underwater gas hydrate deposits.6 dwg