Characterizing static reservoir connectivity of deep-water slope deposits using detailed outcrop-based facies models, Tres Pasos Formation, Magallanes Basin, Chilean Patagonia

As petroleum exploration ventures further offshore, understanding the architecture of deep-water slope deposits is becoming increasingly important. With well costs of 100s of millions of dollars, limited seismic resolution, and sparse well control, insight beyond subsurface well and seismic reflectivity is of increased importance. Leveraging outcrop analogs can aid in understanding the impact of inter- and intra-channel architecture (e.g., facies geometries) on pay connectivity. Such architecture is generally below the resolution of subsurface seismic-reflectivity imaging and is difficult to deduce from well data.;A high-resolution digital outcrop model of stacked, deep-water channel fills from the Laguna Figueroa section of the well-exposed Late Cretaceous Tres Pasos Formation in Chilean Patagonia was created. This model is based on > 1,600 meters of cm-scale measured section, > 100 paleoflow measurements, and thousands of differential global positioning system (dGPS) points (10 cm accuracy) from a two- to three-dimensionally exposed outcrop belt ~2.5 km long and 130 m thick. The model is used to elucidate the effects of facies relationships and intrachannel stratigraphic architecture on the connectivity of a series of stacked channel fill deposits.;The model captures observed outcropping facies geometries at a resolution of 2 m horizontally and 0.25 m vertically (~600M cells). Emphasis was placed on representing accurate and detailed intrachannel element architecture amongst 18 distinct channel fills, or elements, which comprise 3 channel complexes. Three channel element width (200, 250, and 300 m) models and two channel base drape (CBD) scenarios were created, for a total of 6 models. These models allow for an assessment of how width and internal channel architecture impact static connectivity. Static connectivity analyses were performed on the models by 1) calculating a value for each model overall; 2) by channel element pair to determine connectivity changes through stratigraphy; and 3) down depositional-dip to capture planview variability in connectivity data. Because such a fine-scale model would likely not be used in flow simulations, an upscaling analysis was performed to explore the degradation of the intrachannel architectural information, and the effects of this on connectivity, by varying vertical and horizontal sizes of cells.;Results of an exhaustive static connectivity analysis show that the CBD scenarios strongly impact sandstone connectivity and that smaller channel element widths are more susceptible to poor connectivity and disconnected sandstone geobodies. Net-to-gross (NTG) calculated from the models is used to illustrate nuances in the relationship between NTG and connectivity. Upscaling the models consistently increases static connectivity, and small changes in cell geometry impact model architecture, which can artificially induce connectivity. Ultimately, this work aims to constrain uncertainty related to sub-seismic scale architecture, as well as its impact on reservoir connectivity, by providing concrete connectivity data which can be used to build more predictive models.