Outcrop analog studies have long been used to define subsurface correlation strategies and improve predictions of reservoir heterogeneities that can complicate production behavior. Recent advancements in geographic information software, 3D geologic modeling techniques, and survey equipment have the potential to revolutionize outcrop analog studies. A workflow is developed to create digital outcrop models using a reflectorless total station, a digital camera, Erdas Photogrammetry Module™, and Gocad™ to document complex stratal variations across kilometers-long outcrops. Combining outcrop digital elevation models with orthorectified photographs and detailed sedimentologic logs provides a framework for static 3D reservoir analog models. Developed methodologies are demonstrated by mapping rock variations and stratal geometries within several kilometers-long, sub-parallel exposures of the Lower Sego Sandstone in San Arroyo Canyon, Book Cliffs, Utah. The digital outcrop model of the Lower Sego Sandstone documents complex bedding geometry and facies distribution within two sharp-based sandstone layers. A mapping of allostratigraphic surfaces through the digital outcrop model provided a framework in which to analyze facies variations. These surfaces included: 1) Basal erosion surfaces of these layers interpreted to have formed by tidal erosion of the sea floor during shoreline regression; 2) a high relief erosion surface within the upper layer interpreted to have formed during lowstand fluvial incision; and 3) top contacts of layers defined by abrupt fining to marine shale, which are interpreted to record marine ravinement during transgression. Facies variations within the lower layer include low sinuosity distributary channel deposits incised into highly marine bioturbated sandstone. Deposits above the high-relief erosion surface within the upper layer are a classic valley fill succession, which processes upward from lowstand fluvial channel deposits, to heterolithic estuarine deposits, and finally to sandy landward-dipping beds of an estuarine mouth shoal deposit. The digital outcrop model allows surfaces and facies observation to be mapped within a structured 3D coordinate system to define reservoir analog models.

Outcrop analog studies have long been used to define subsurface correlation strategies and improve predictions of reservoir heterogeneities that can complicate production behavior. Recent advancements in geographic information software, 3D geologic modeling techniques, and survey equipment have the potential to revolutionize outcrop analog studies. A workflow is developed to create digital outcrop models using a reflectorless total station, a digital camera, Erdas Photogrammetry Module™, and Gocad™ to document complex stratal variations across kilometers-long outcrops. Combining outcrop digital elevation models with orthorectified photographs and detailed sedimentologic logs provides a framework for static 3D reservoir analog models. Developed methodologies are demonstrated by mapping rock variations and stratal geometries within several kilometers-long, sub-parallel exposures of the Lower Sego Sandstone in San Arroyo Canyon, Book Cliffs, Utah. The digital outcrop model of the Lower Sego Sandstone documents complex bedding geometry and facies distribution within two sharp-based sandstone layers. A mapping of allostratigraphic surfaces through the digital outcrop model provided a framework in which to analyze facies variations. These surfaces included: 1) Basal erosion surfaces of these layers interpreted to have formed by tidal erosion of the sea floor during shoreline regression; 2) a high relief erosion surface within the upper layer interpreted to have formed during lowstand fluvial incision; and 3) top contacts of layers defined by abrupt fining to marine shale, which are interpreted to record marine ravinement during transgression. Facies variations within the lower layer include low sinuosity distributary channel deposits incised into highly marine bioturbated sandstone. Deposits above the high-relief erosion surface within the upper layer are a classic valley fill succession, which processes upward from lowstand fluvial channel deposits, to heterolithic estuarine deposits, and finally to sandy landward-dipping beds of an estuarine mouth shoal deposit. The digital outcrop model allows surfaces and facies observation to be mapped within a structured 3D coordinate system to define reservoir analog models.

Outcrop analogue studies of fluvial sedimentary systems are often undertaken to identify spatial and temporal characteristics (e.g. stacking patterns, lateral continuity, lithofacies proportions). However, the lateral extent typically exceeds that of the exposure, and/or the true width and thickness are not apparent. Accurate characterisation of fluvial sand bodies is integral for accurate identification and subsequent modelling of aquifer and hydrocarbon reservoir architecture. The studies presented in this thesis utilise techniques that integrate lidar, highresolution photography and differential geospatial measurements, to create accurate three-dimensional (3D) digital outcrop models (DOMs) of continuous 3D and laterally extensive 2D outcrop exposures. The sedimentary architecture of outcrops in the medial portion of a large Distributive Fluvial System (DFS) (Huesca fluvial fan) in the Ebro Basin, north-east Spain, and in the fluvio-deltaic succession of the Breathitt Group in the eastern Appalachian Basin, USA, are evaluated using traditional sedimentological and digital outcrop analytical techniques. The major sand bodies in the study areas are quantitatively analysed to accurately characterise spatial and temporal changes in sand body architecture, from two different outcrop exposure types and scales. Several stochastic reservoir simulations were created to approximate fluvial sand body lithological component and connectivity within the medial portion of the Huesca DFS. Results demonstrate a workflow and current methodology adaptation of digital outcrop techniques required for each study to approximate true geobody widths, thickness and characterise architectural patterns (internal and external) of major fluvial sand bodies interpreted as products of DFSs in the Huesca fluvial fan, and both palaeovalleys and progradational DFSs in the Pikeville and Hyden Formations in the Breathitt Group. The results suggest key geostatistical metrics, which are translatable across any fluvial system that can be used to analyse 3D digital outcrop data, and identify spatial attributes of sand bodies to identify their genetic origin and lithological component within fluvial reservoir systems, and the rock record. 3D quantitative analysis of major sand bodies have allowed more accurate width vs. thickness relationships within the La Serreta area, showing a vertical increase in width and channel-fill facies, and demonstrates a 22% increase of in-channel facies from previous interpretations. Additionally, identification of deposits that are products of a nodal avulsion event have been characterised and are interpreted to be the cause for the increase in width and channel-fill facies. Furthermore, analysis of the Pikeville and Hyden Fms contain sand bodies of stacked distributaries and palaeovalleys, as previously interpreted, and demonstrates that a 3D spatial approach to determine basin-wide architectural trends is integral to identifying the genetic origin, and preservation potential of sand bodies of both palaeovalleys and distributive fluvial systems. The resultant geostatistics assimilated in the thesis demonstrates the efficacy of integrated lidar studies of outcrop analogues, and provide empirical relationships which can be applied to subsurface analogues for reservoir model development and the distribution of both DFS and palaeovalley depositional systems in the rock record.

The Lower Ordovician El Paso Group is a >400-m-thick carbonate succession exposed in the Franklin Mountains, El Paso, Texas. The El Paso Group contains multiple breccias related to collapsed-paleocave systems. These breccias have been documented as having formed during the top-Lower Ordovician Sauk depositional supersequence lowstand. Evidence presented in this study suggests that cave formation may have been as much as 350 million years younger and related to Laramide oblique right lateral compression. Regardless of the timing of formation, the breccias mapped in this study are of collapsed paleocave origin based on breccia clast organization and matrix content. Speleogenetic models are compared against observations of breccia distribution by direct field observations and mapping on sub-meter airborne light detection and ranging or lidar data. Point vectors were defined for every point within study area to highlight subtle changes in outcrop erosional profile for mapping geological features directly on the lidar point cloud. In addition, spectral data from airborne photography and hyperspectral image analysis were used assist in geological contact definition. A digital outcrop model was constructed from 3D geologic mapping results from which spatial statistic were extracted and used to reconstruct collapsed paleocave breccia bodies. The resultant breccia geometries were compared against laser-scanned modern cave dimensions, from Devil's Sinkhole, Rocksprings, Texas, and used in analysis of conceptual models for cave formation. The breccias of the southern Franklin Mountains follow linear trends that closely match Riedel shear fracture patterns predicted from right-lateral oblique compression. Stress orientations that match right-lateral oblique compression in the Phanerozoic of the El Paso region are related to the Laramide orogeny. The relationship of observed structures and the orientation of collapse breccias may indicate that southern Franklin Mountain breccia bodies are the result of a solution-enhanced tectonic karst system. / text