HYDRATE EXISTENCE DOMAIN SURVEY METHOD AND SURVEY SYSTEM

摘要

PPROBLEM TO BE SOLVED: To provide a hydrate existence domain survey method and a survey system capable of surveying a methane hydrate existence domain in a sea-bottom stratum where a sea-bottom pseudo reflection surface exists. PSOLUTION: A sea-bottom stratum structural drawing is drawn by using a low-frequency band from a measurement result of seismic survey using a seismic source having a high-frequency band, and a signal spectrum of a measurement result on the furthermore upside than the sea-bottom pseudo reflection surface is determined on a place of the sea-bottom pseudo reflection surface specified from the stratum structural drawing, and a portion wherein a spectrum is large over the whole frequency of the survey and the spectrum intensity in a high-frequency band is greater than the spectrum intensity in a low-frequency band is extracted. If an extracted portion does not exist, it is determined that the hydrate does not exist, and if an extracted portion exists, it is determined that the hydrate exists in the extracted portion. PCOPYRIGHT: (C)2008,JPO&INPIT