Mapping submarine fan systems in the Bone Spring Formation, Delaware Basin, Texas and New Mexico

The Bone Spring Formation in the Delaware Basin of Texas and New Mexico comprises rhythmically stacked submarine fan systems of alternating carbonate- and siliciclastic-dominated intervals deposited during the middle Permian (Leonardian). Regional subsurface mapping delineates the geometry and distribution of these systems, providing insight into basin-scale stratigraphic architecture and petroleum resource potential. Net-to-gross maps of three primary lithology classes—carbonate, sandstone, and mudstone—were constructed from digitized lithology logs describing well cuttings at ten-foot intervals. Sandstone intervals, which form the primary horizontal drilling targets and petroleum reservoirs, occur as elongate, fan-shaped fairways along the basin axis but remain detached from correlative siliciclastic deposits on the shelf. These fans exhibit aggradational stacking and onlap relationships against an incised basin margin crossed by multiple submarine canyons. Paleo-bathymetric variations further influenced fan geometry, stacking patterns, and connectivity, creating lateral stratigraphic heterogeneity across the basin floor. Collectively, these observations support the interpretation that sand within the Bone Spring Formation was not supplied by major fluvial-deltaic systems but rather by reworking of littoral sediment during episodes of shelf flooding and subsequent funneling through submarine canyons.