Quantitative Characterization of the Sedimentary Architecture of Shallow-Marine and Paralic Reservoir Analogs: A Database Approach

Abstract

Shallow-marine and paralic clastic depositional systems are described by a large volume of sedimentological, architectural and geomorphological data. A new method that enables the convergence of these datasets into a common descriptive scheme facilitates the identification and application of potential outcrop and modern hydrocarbon-reservoir analogs. To this end, a database has been developed for the collation of data in standardized format, in a way that allows significant comparisons between different depositional systems, and the derivation of consistently defined attributes that can be applied in subsurface studies. The Shallow Marine Architectural Knowledge Store is a relational database devised to include data on the sedimentary architecture of shallow marine and paralic ancient depositional systems, and on the geomorphic organization of corresponding modern environments. The database incorporates data on sedimentary bodies and surfaces and geomorphic units, which are classified on descriptive (e.g. grainsize) and interpretive (e.g. sub-environment) categories, and characterized on a variety of attributes (e.g. geometries, spatial relationships, hierarchical relationships). Depositional systems, and stratigraphic intervals or planform segments thereof, are classified on descriptive parameters (e.g. shelf gradient) and controlling factors (e.g. tidal regime) to allow the selection of relevant outcrop or modern analogs. The database can be queried to return a quantified characterization of multiple analogs, and data can be synthesized in models that incorporate uncertainty related to variability in sedimentary heterogeneity. To illustrate the range of genetic units types, depositional systems, associated data and potential applications, example database output is showcased relating to: - the hierarchical arrangement and scaling relationships of architectural elements that form constructional units in Quaternary deltas of different types; - the facies organization of nearshore sandstone belts and the geometry of associated parasequences, from the Upper Cretaceous of the Western Interior Seaway in Utah (USA); - the geometry of modern geomorphic features, and their relations with the geometry of architectural elements interpreted as the preserved product of the morphodynamic evolution of corresponding landforms. Particular attention is paid to how the database output can be applied to the construction of accurate, quantitative 3D geological models.

AAPG Datapages/Search and Discovery Article #90259 ©2016 AAPG Annual Convention and Exhibition, Calgary, Alberta, Canada, June 19-22, 2016