Porosity and permeability of the English (Lower Cretaceous) sandstones

Abstract

The petrophysical properties of the Wealden sandstones in southeast England are scarcely documented in the literature despite their potential to study porosity, permeability, and sedimentary architecture in three dimensions. For the first time in the published literature, the porosity and permeability of the Wealden sandstones within the Ashdown and Wadhurst Clay Formations (Late Berriasian-Middle Valanginian) are presented from the Weald Basin in southeast England. The Wealden sandstones have porosity between 6.3% and 13.2% with an average of 9.9%. Permeability ranges from 0.4mD to 11.9mD with an average of 3.1mD. The Cliff End Sandstone (Wadhurst Clay Formation) with the highest porosity and permeability has the best quality, followed by the Top Ashdown Sandstone, the upper Ashdown Sandstone and by the lower Ashdown Sandstone. The main controls on porosity and permeability in these sandstones are grain sizes, grain shapes, and sorting and these are directly linked to their depositional environment. This work aims to stimulate further investigations into the petrophysical properties of the Wealden sandstones and their potential as possible analogues for fluvial reservoirs.