Abstract Few major dam sites are investigated today without recourse to aerial photography. Not long ago aerial photos were used almost solely for the production of planimetric and topographic maps. In dam investigations these maps were used to determine storage capacities of reservoirs and estimate earthwork quantities. At present, however, specialists are concentrating on the analysis and interpretation of diagnostic details of the natural and cultural landscape recorded on aerial photos. Among the many studies requiring experienced specialists are the detection of unstable slopes, the discovery of various types of selected construction materials, prediction of foundation conditions, and the location of tentative earth and concrete structures to take advantage of favorable geologic conditions.

ABSTRACT Production-scale variability in Mississippian reservoirs of the U.S. midcontinent is poorly understood, largely due to distant spacing of subsurface wells and the lack of outcrops that provide a 3-D distribution of potential reservoir facies. This study utilizes exposures of Upper Mississippian (Meramecian to Chesterian in age) lithofacies in a quarry to develop a 1st-order 3-D facies model at a production or enhanced-production scale (<40 ac [<16.2 ha]). By utilizing photogrammetry to stitch and georeference high-resolution aerial photos, 3-D representations of outcropping walls and pavement were created at a submeter resolution and serve as valuable tools for the visualization of bed and facies relationships in 3-D space. Drone-based aerial and orthogonal photography was used to capture images and create 3-D models of inaccessible outcrop areas. These models were then imported as base surfaces to geostatistical reservoir modeling software (Petrel), in which they were integrated with petrographic and sequence-stratigraphic data to model facies and porosity relationships. Various algorithms and variogram lengths were tested and compared to high-resolution outcrop data to determine the most appropriate workflow for future subsurface modeling. The Petrel-based facies and porosity models illustrate the lateral and vertical variability that exists in outcrop while providing detailed approximations of subsurface reservoir heterogeneity.

ABSTRACT The emergence of Three Rooker Bar over the past 22 years has presented a unique opportunity to document, through a combination of aerial photography and field observations, the depositional processes and morphologic changes associated with the formation of the island. Three Rooker Bar is situated within the only major gap in the otherwise continuous barrier island coast of Pinellas County Florida, between Honeymoon Island and Anclote Key. The island is bounded to the west by the eastern Gulf of Mexico and by the relatively shallow St. Joseph Sound to the east. The island first became emergent in 1969, although much of its growth has occurred within the last few years. It is essentially pristine and undeveloped, approximately 2 km long and nearly 20 m at its widest spot. The island has a stable, vegetated back beach and dune complex, extensive shoals off the southern end and well developed algal covered tidal flats which overly back barrier washover deposits. Twenty two vibracores, taken throughout the area, are the basis for three Holocene lithofacies which represent six depositional environments including barrier island, back barrier washover, nearshore bar, coastal bay, and mangrove/salt marsh. Lithofacies are defined based on mud content, shell content and taxonomy, organic content, sedimentary structures and similarity to modem surface sediment deposits. Excellent aerial photo coverage allows direct correlation of these lithofacies with the physical processes which led to their deposition. Absolute interpretation of the depositional environments of these facies is therefore possible. Results of this method of correlation have led to the interpretation of in-place, upward shoaling of linear sand bars as the primary mode of island formation. Continued growth as well as periodic breaching of topographically lower areas, can be expected for this island in the future.

Abstract Glaciers are a significant natural resource in Alaska and the Western United States, covering respective areas of ~74,600 and 688 km 2 ( Dyurgerov, 2002 ; Fountain et al., 2007 ). A large percentage of these glaciers exist within the boundaries of lands managed by the U.S. federal government. For example, glaciers in Wrangell-St. Elias National Park and Preserve and Denali National Park and Preserve in Alaska cover a total area of ~20,000 km 2 ( Adema, 2004 ). In contrast to geologic processes that operate on time scales on the order of thousands or even millions of years, significant glacier change can occur within a human lifetime. The dynamic nature of glaciers strongly influences the hydrologic, geologic, and ecological systems in the environments in which they exist. Additionally, the sensitive and dynamic response to changes in temperature and precipitation make glaciers excellent indicators of regional and global climate change ( Riedel and Burrows, 2005 ). Long-term monitoring of glacier change is important because it provides basic data for understanding and assessing past, current, and possible future conditions of the local, regional, and global environment. A basic understanding of local and regional environmental systems is critical for responsible land management and decision-making.