Multiple-Point Geostatistics Simulation of the Natural Gas Hydrate Distribution at the Pore Scale

Heat and mass transfer in a natural gas hydrate reservoiris stronglyaffected by the hydrate pore habit. Some present simplified modelsused in numerical simulation of a hydrate-bearing sediment are difficultto catch features of the hydrate distribution in sediments precisely.Using an improved multiple-point geostatistics simulation method,this study generates a series of images of porous media that reproducethe hydrate distribution information on a training image. The improvedalgorithm completely solves the problem that the hydrate blocks theboundary and makes the variogram and visual properties similar tothe training image. Some typical phenomena of hydrate formation appearin the results, such as Ostwald ripening and the shift of hydratepore habit from grain coating toward pore filling. The feasibilityof predicting the pore habit of a hydrate with time using this novelmethod is proven by the verification case. This study offers a newapproach to predict the distribution behavior of a hydrate, and thisalgorithm may be applied widely by scanning training images from differentreservoirs.

Automated summary

This study employs an improved multiple-point geostatistics simulation method to generate a series of images of porous media that accurately reproduce the distribution of hydrates in sediments. The algorithm successfully solves the problem of hydrate blockage and ensures similarity in variogram and visual properties with the training image. The feasibility of predicting the pore habit of hydrates with time using this novel method is proven by a verification case. This research offers a new approach to predict hydrate distribution behavior and the algorithm may be widely applied by scanning training images from different reservoirs.