Well Logging Parameters Of Hydrocarbon Bearing Sandstones Composed Of Sand, Silt And Shale; Evaluation Of Water Saturation, Porosity And Grain-Size Distribution

In one of the largest oil and gas bearing structures of Hungary grain size distribution of sandstones shows a great variety; besides sand fractions, both silt and shale fractions occur in considerable quantities. We have found that the dominant grain size affects to a great extent the values of well logging parameters. We have elaborated mathematical models and formulae to show the relationship of grain size distribution, reservoir parameters and well logging characteristics. By means of these formulae the value of some reservoir parameters can be determined on the basis of well logging data. We are showing practical evaluation of well logging for the determination of water saturation, porosity, and grain size distribution.