Study of a TX field Miocene carbonate build-up: Integration of sedimentological data with modern carbonate analogue and 3D seismic characterization to establish carbonate facies modelling workflow

Facies modelling of the Central Luconia carbonate build-up is a complex process due to the multi-scale heterogeneity of carbonate reservoirs in terms of facies, stratigraphy and pore structure variations. The objective of this paper is to integrate core, modern carbonate platform and 3D seismic data for building a conceptual model to establish a carbonate build-up facies modelling workflow. The first part of the workflow builds a conceptual geological model via the integration of core and modern carbonate build-up analogue data. The sedimentological study began by describing the core facies units of a field, which was then correlated to the well logs. Five reservoir zones comprising of a total thickness of approximately 323m are identified, with Zone 3 and upper Zone 5 the tighter zones when compared to Zones 1, 2 and 4. The subsequent study of modern analogue is conducted to infer the lateral distribution of various facies throughout the carbonate build-up. The second part of the research involves the characterization of 3D seismic of the build-up calibrated with core and modern analogue data. Seismic interpretation has distinguished six reservoir surfaces: Top of carbonate (ToC), TZ2, TZ3, TZ4, TZ5, and TZ6. Reservoir zones from core-to-well correlation is used for tying the well to 3D seismic, ensuring distinct correlations. In addition, seismic attributes are generated from 3D seismic to distinguish platform geometries and for seismic stratigraphy analysis. In summary, conceptual modelling is a crucial step in carbonate facies modelling workflow requiring extensive amount of time for iterating and refining, prior to conducting digital facies modelling.