Golmshtok A. Ya.
The thermobaric regime of hydrate-bearing sediments is investigated in this paper by solution of the phase transition problem gas hydrate — gas + water when both linear and metallic cylindrical heat source is switched on. It is shown that the use of a needle probe in situ is strongly limited in the seas of the usual (most common) type with a bottom water temperature of about 3 °C for the study of gas hydrates accumulations on the sea bottom. Such a use is possible there only in case of very high linear source power. It was determined that only at the bottom of «warm» seas the use of a needle probe can allow not only to detect the presence of gas hydrates in bottom sediments, but also to evaluate the properties of these sediments by the nature of the temporal variations of both temperature and pressure on the surface of the probe. Since the characteristics of time changes of gas pressure near the probe are generally more differentiated than similar temperature dependencies, a high-precision pressure sensor must also be built into the probe designed for in situ use in hydrate-bearing bottom sediments. The obtained solution of the phase transition problem can serve as a basis for the process of the experimental data interpretation.