Chapter 12
High-resolution Facies Architecture of Heterolithic Tidal Deposits: An Integrated Outcrop and Electrofacies Analysis of a Complex Reservoir

Renu Gupta
Schlumberger Data and Consulting Services
London, U.K.

Howard D. Johnson
T. H. Huxley School, Imperial College
London, U.K.

ABSTRACT

Sandstones deposited in tide-dominated estuarine and deltaic environments are characterized by a distinct range of heterolithic facies, which display a hierarchical distribution of mudstone layers and gross sandstone/mudstone content. In the subsurface, these heterolithic facies are interbedded strata of sandstone and mudstone, ranging in thickness from millimeters to centimeters. They cannot be resolved by conventional well logs. Consequently, facies discrimination in these successions is often crude and does not allow genetically significant rock types to be distinguished. This severely limits the analyses of facies sequence necessary to deliver a high-resolution model of reservoir architecture and predictions of rock properties appropriate for reservoir modeling.