Logging Interpretation Model and Equation of Gas Hydrate Saturation

Ning Li^1,2, Wenjie Sun^1,2, Xintong Li³, Zhou Feng^1,2, and Hongliang Wu^1
1Research Institute of Petroleum Exploration & Development (RIPED), PetroChina
²Peking University
³The University of Edinburgh

As an important unconventional resource, more and more attention has been paid to the natural gas hydrate exploration worldwide. Nowadays, traditional interpretation models and calculation formulas of oil saturation used in sand-shale well logging, like Archie equation and dual water model, are still adopted in the calculation of hydrate saturation. Since the formation of hydrate is greatly affected by environment, its distribution pattern in layers is more complex than oil or gas. Gas hydrate can not only fill in formation pores like oil and gas, but also form supporting skeleton in the form of particles, or even accumulate individually as layers. Therefore, obvious error might be happened when calculating hydrate saturation by using the traditional methods, and then lead to misalignment of reserves calculation. This paper establishes a new logging interpretation model of gas hydrate saturation, and determines a more reasonable interpretation equation which has applied to the scene interpretation. The application result shows that the interpreted gas hydrate saturation is more close to the real saturation which analyzed from the hydrate reservoir sampling.

AAPG Datapages/Search and Discovery Article #90180©AAPG/SEPM/China University of Petroleum/PetroChina-RIPED Joint Research Conference, Beijing, China, September 23-28, 2013