A METHOD FOR GAS HYDRATE RESOURCE ESTIMATION——AN EXAMPLE OF PRELIMINARY ESTIMATION OF GAS HYDRATES IN THE NORTHERN CONTINENTAL SLOPE, SOUTH CHINA SEA

In this paper one method for estimating gas hydrate potentials was put forward based on the general gas hydrate thermodynamics and the basic calculus theory;subsequently a preliminary estimation of gas hydrates possibly occurring in the northern continental slope of the South China Sea(SCS) was carried out.Firstly the gas hydrate potential area was divided into various micro-volume blocks,and the whole gas hydrate potential volume was calculated by the integral accumulations.Afterwards the multiplication of the gas hydrate potential volume by the relevant subsurface sediment porosity,gas hydrate saturation and the hydration coefficient,which are referenced to the world well-known gas hydrate parameterizations,was conducted to estimate the gas hydrate potential resource in the northern SCS.The calculated result approximately corresponds to 6.3×10¹³ m³ of methane at the STP.It means that the estimated gas hydrate amount is generally equivalent to the magnitude of the Blake Ridge offshore America,the Nankai Trough offshore Japan,and the northern Gulf of Mexico offshore America(10¹³ m³ of methane) respectively.This suggests a huge gas hydrate potential resource in the northern continental slope of SCS.Of course it still needs to be checked or confirmed by the field investigation.