Study of pneumatic sources of elastic waves for marine seismic exploration

Abstract

An extensive use of geophysical methods necessitates the development of new methods and improvement of existing methods for seismic exploration to provide reliable data on the structure of the environment in difficult geological conditions. Therefore, it is especially relevant to solve the problems arising in marine petroleum geophysics, which require constant improvement of the methodology and technology of work, and the development and implementation of the advanced seismic equipment. Pneumatic sources that use compressed air as a working medium are among the most effective non-explosive sources for marine seismic exploration. Pneumatic sources exhibit high-energy characteristics, reliability and versatility. Compressor equipment that provide pneumatic sources with high-pressure compressed air is relatively easy to embed into the marine vessel’s power system. The above requires the development and improvement of theoretical methods for studying dynamic problems of a liquid half-space with buried sources of various types. A theoretical description of the formation of an elastic signal in water is given in a number of works. However, the authors of these works do not perform the analysis of gas transportation. The paper considers a number of characteristics of gas flow at a subsonic speed along the high-pressure hose from a vessel’s compressor unit to a pneumatic source. The airflow rate in the receiver-pneumatic source system is determined, and the friction force at a quasi-steady isothermal mode of gas flow is calculated. The paper presents recommendations for planning geophysical works.