Abstract:

Gas hydrates are ice-like crystalline substances composed of cages of water molecules that host low molecular weight gases mainly methane. Bottom simulating reflector (BSR) in seismic profile is an important seismic indicator for existence of gas hydrates.Because gas hydrates which have different component have relatively stable relationships of temperature and pressure respectively, pressure, temperature and even heat flow in gas hydrate stability zone can be estimated based on the data of existence of gas hydrates consequently. Using the calculating method mentioned above, typical seismic profiles in the northern of the South China Sea, where BSR can be recognized obviously, were chosen to calculate these geothermal data. The contrast between the calculated values and the measured values show that the calculated error can be limited in 12%.To a certain extent,estimation of the heat flow from seismic data of gas hydrate can provide  reliable data of heat flow for academic research; Furthermore, the data of heat flow and the experiential formula which were calibrated by measured values of heat flow can be used to predict the depth of BSR and the thickness of gas hydrate stability zone.

Key words: gas hydrate, BSR, heat flow, the northern of the South China Sea