Carbonate depositional environments are inherently heterogeneous because of the superposition of sedimentary and diagenetic processes during successions of relative sea level changes. Projects in the modern environment use a combination of various types of remote sensing data and surface samples to capture the spatial trend metrics of sedimentary bodies. Surface samples from northwestern Great Bahama Bank are intended to refine the facies maps of this classic modern platform system.
Understanding flow, compartmentalization and mineralization in reservoirs depends on knowledge of the 3-D architecture of sedimentary structure and fracture network in the rock volume around the borehole. Several of our projects aim to increase our understanding of the lateral and vertical heterogeneity of facies and fractures. To achieve this goal, we have developed a new generation of 3-D Ground Penetrating Radar to retrieve the sub-meter scale variability of facies and flow units from Pleistocene grainstone shoals in the Miami Oolite and for fractures in several locations around the world. Seismic data from various regions are used to examine the evolution of carbonate systems in different tectonic settings and assess the influence of tectonic activity, sea level changes and sediment supply on the carbonate depositional system. Currently, we study seismic data from the Bahamas-Cuba foreland basin to decipher carbonate platform drowning as a result of increased subsidence during the formation of this foreland basin, and to delineate the evolution of the Gulf Stream from sediment drifts in the Bahamas region.
Reservoir heterogeneities and the large-scale distribution of reservoir quality dolomite have been the focus of projects in the Mississippian Madison Formation. Currently we are assessing the dolomitization processes in the Madison Formation and the correlation of the dynamics of the evolving foreland basin on the evolution of these ramp carbonates. In addition, we continue our research in relating mechanical stratigraphy to sequence stratigraphy. These projects will provide us with a methodology to predict to a certain degree the fractures from facies and stratigraphic information.

This project will generate high-resolution habitat characterization maps for all surveyed cold-water coral sites in the Straits of Florida. The lateral variability of each habitat facies will be determined. Morphometric parameters will be calculated for each site and statistically correlated with environmental factors, including current regime and antecedent topography.

This project will refine the documentation of the complex facies heterogeneity of juxtaposed ages, environments and compositions on New Providence Island using the working hypothesis that the island formed through vertical and lateral accretion of marine and eolian deposits during the last three Pleistocene sea-level highstands (MIS 5, 9, and 11). Detailed stratigraphy both in outcrop and subsurface will be used to map out deposits across the island. This mapping, combined with detailed petrography of all units, will create a depositional and diagenetic history of New Providence Island. Radiometric dating techniques will give the precise timing of deposition that is needed to relate the deposits to Pleistocene sea level changes. The beach facies within each one of the stratigraphic packages will provide an anchor point for the amplitude of sea level in each of the highstands.

Windward margin stratigraphy and heterogeneity is assessed through mapping the modern facies and coring the Pleistocene para- sequence-scale stratigraphy along the ~200 km windward margin in the Exumas, Bahamas. The results from this three-year study will deliver a baseline for improved carbonate heterogeneity estimation and reservoir characterization in windward margin settings.

Carbonate platforms are notoriously complex due to vertical and horizontal heterogeneity that makes the prediction of grain size, porosity, and sediment morphometrics difficult. Glover’s Reef is a 260-sqkm reef-rimmed platform off the coast of Belize and the subject of both forward sediment and reservoir modeling studies. In the modern, the windward-leeward asymmetry and over 800 patch reefs in the lagoon introduce considerable heterogeneity in both facies and morphology. Rotary cores, over 100 km of seismic lines, satellite imagery, petrophysical measurements, and sediment samples from patch reefs and the marginal reef will allow rigorous quantitative assessment of carbonate heterogeneity in multiple dimensions and scales for the first time.

Mixed carbonate siliciclastic reservoirs are highly complex systems with heterogeneous properties because of the intertwining of different facies and the often complicated diagenesis. Adequate reservoir characterization can only be achieved by integration of geometric, lithologic, and petrophysical data. The level of detail necessary to capture the small-scale variations of reservoir quality lies commonly below seismic resolution and therefore requires the incorporation of detailed outcrop observations with larger scale seismic interpretations. The aim of the proposed project is to combine outcrop and subsurface data for the development of a detailed model of the Upper Jurassic – Lower Cretaceous mixed carbonate siliciclastic system in the Neuquén Basin, Argentina.

Project Objectives
• Integrate the results of the sedimentologic, sequence and chemo-stratigraphic and tectonic analyses for a comprehensive model of the Madison ramp.
• Relate the results of the large regional studies to potential exploration plays and summarize the implications of local heterogeneities to production scale problems in the Madison ramp and carbonates in general.
• Outline the distribution, genesis, and petrophysical variability of reservoir quality dolomite within the Madison Formation.

The principal factor that appears to determine the growth and facies geometries of fringing reefs is the available accommodation space and changes in relative sea-level. The Pleistocene reefs that developed over the past 1.8 million years provide the best opportunity to study the complex three-dimensional architecture and controlling factors of fringing reef development during high frequency sea level cycles. This project aims to characterize the composition, morphology and distribution of fringing reefs developed along the southern coast of the Dominican Republic. This study will be conducted in conjunction with the petrophysical characterization (see Ditya, Geophysics and Petrophysics).