Accurate evaluation device for vertical content distribution of active excitation type seabed hydrate reservoir

Abstract

The invention relates to content determination of seabed hydrates, in particular to an active excitation type accurate evaluation device for vertical content distribution of a seabed hydrate reservoir. Comprising a gas collecting mechanism and a screw-in type long sleeve, the gas collecting mechanism is fixed above the screw-in type long sleeve, the screw-in type long sleeve is in a tubular design, and a plurality of groups of thermal excitation mechanisms are fixed on the outer wall of the screw-in type long sleeve at intervals in the axial direction of the screw-in type long sleeve; each group of thermal excitation mechanism comprises a plurality of thermal exciters which are positioned in the same horizontal direction and are uniformly arranged at intervals in the annular direction of the long sleeve; the side wall of the screw-in type long sleeve is further provided with a temperature sensor and a plurality of sets of directional guide channels arranged at intervals in the axial direction of the long sleeve, and the temperature sensor and a set of directional guide channels are arranged above each set of thermal excitation mechanism. And each group of directional guide channels comprises a plurality of directional guide channels which are positioned in the same horizontal direction and are uniformly arranged at intervals in the circumferential direction of the long sleeve.

Description

Technical field [0001] The present invention relates to the content determination of subsea hydrate, in particular, an active excitation subsoffice reservoir vertical content distribution precision assessment device. Background technique [0002] Hydrate is a fro-shaped crystalline substance formed by natural gas and water under high pressure low temperature, and is also referred to as * # * can be burning ice * # *. At this stage, the development and drilling of hydrates in the world are in hot and hot, and hydrates are increasingly becoming the energy focus of human available. [0003] It is critical to the location and distribution characteristics of natural gas hydrates, and it is also the primary premise of follow-up. The current popular detection technique mainly includes acoustic detection technology, time domain reflection technology, impedance detection technology, TDR and other test combined detection techniques. The most important effective detection method at this sta...

AI Technical Summary

Problems solved by technology

[0005] At present, the mainstream way to detect the distribution and content of seabed gas hydrate reservoirs is mainly to rely on geophysical monitoring of cold seep plumes. First, determine the distribution range of hydrates, and then use marine geophysical prospecting methods to conduct large-scale assessment. After the assessment is completed, Due to the shortcomings of inaccurate geophysical detection methods, relying on manual experience, and the inability to conduct detailed surveys of hydrate reservoirs, it is necessary to conduct logging drilling and sampling at a certain point based on expert judgment to realize hydrate reservoirs in the area. Definition of distribution

[0006] However, after the logging drilling and sampling work is completed, due to the unavoidable disturbance of the soil during the drilling process, the interaction between the seawater and the soil caused by the leftover drilling holes, and the reduction of the ballast protection effect of the overlying soil layer, it will directly lead to excessive porosity. Water pressure, temperature, salinity, PH, etc. change greatly, and the temperature field and pressure field of the reservoir have a great influence on the occurrence and distribution of gas hydrate, which will directly lead to the secondary formation of gas hydrate. distribution, which in turn affects the accurate assessment of the vertical content distribution of seafloor hydrate

In summary, the existing technology cannot accurately evaluate the secondary distribution of gas hydrates caused by drilling

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