During 2004–2010, we studied the sand dunes of Oman using trenches, optically stimulated luminescence age dating, and modern wind data. This work was undertaken for Petroleum Development Oman to define modern analogs for ancient dune reservoirs that produce oil and gas in the sultanate. An unintended consequence of our work was the recognition of a band of high wind energy along the east coast of Oman that might be suitable for commercial wind power extraction, especially during the peak wind season of the Indian monsoon. Our geological work indicates that this basic wind regime has been in place for at least 200,000 yr and is thus not a fluke of present-day climate.

Abstract Exhaustive study of the historical use of energy is paramount in forecasting future use accurately. The much-needed detailed historical statistical data on human population, energy consumption, and current information about present and possible future sources of energy are assembled in this book. The pubication places particular emphasis on the kind of data that allows trends to be established that can be projected far into the future. It provides the foundation for readers to broaden their knowledge about past energy consumption and its sources of supply. It also furnishes a glimpse into the future of how, and how much, energy will be consumed in the 21st century and what sources will most likely supply it.

Eolian features provide a record of the interaction between winds and the Earth’s surface. Most eolian features are identifiable on aerial photographs; some are large enough to be mapped from LANDSAT imagery. Therefore, eolian features can be remotely identified and interpreted in terms of the strength and flow pattern of the winds that produced them. The techniques that are useful in interpreting wind patterns from eolian features include: (1) Interpretation of wind direction, wind energy, and wind velocity from sand dunes and dune fields; (2) interpretation of wind direction and wind velocity from playas; and (3) interpretation of wind direction and relative wind velocity from scour features, dust and smoke plumes, vegetation patterns, and snow drifts. Wind patterns can be interpreted from eolian features even if the researcher does not have a direct knowledge of the field area nor ancillary data from wind-measuring stations in the region. However, the reliability of the interpretation and the amount of information that can be derived from eolian features are greatly increased if the observer has meteorological and sedimentological information about the area.

Sand dunes, dune fields, playa lakes, playa sediment plumes, blowouts, and scour streaks can be recognized from LANDSAT imagery (resolution ∼80 m) and high-altitude aerial photography (resolution ∼5 m). The abundance of such features in the southern Wyoming test area confirms a major wind corridor with local areas of extremely strong winds indicated by concentrations of eolian features. The abundance of sand and semiarid climate of the area are also important factors in the development of eolian features. Elongate eolian features indicate the direction of flow of strong winds through the area. Streamlines interpreted from these directional indicators parallel streamlines derived from wind measurements obtained by over-flights at low altitudes with specially instrumented aircraft. The streamlines interpreted from imagery yield only a two-dimensional representation of the flow pattern. But, in areas of stably stratified flow, this plan view provides a first approximation of the flow pattern useful for identifying high wind-energy areas. Smaller wind channels within the Wyoming wind corridor display energies at least two to three times greater than adjacent areas. The dimensions and types of eolian features that develop in a high-wind area are greatly influenced by moisture, vegetation, sand supply, cementation, and other factors such that wind strength and/or persistence does not correlate strongly with either the type or dimensions of eolian features. Dune spacings and other harmonic distribution patterns observed in the eolian features, however, correlate with certain windflow patterns. Spaced dune groups and playa clusters are found in areas where gravity waves develop in the near-surface air-flow. Diagonal alignments of eolian features are interpreted to be the result of helical circulation cells aligned parallel to the main flow direction. Strong turbulence is characteristic of scoured areas on the lee side of topographic highs. These local characteristics of windflow can have important effects on average wind energy and on the performance of wind-driven energy systems; thus, they are critical in siting of wind generators and other structures. Relative estimates of average wind velocities can be made by correlating the streamline data and eolian activity in a region of unknown wind energy to a similar area where wind measurements are available. Direct estimates of average wind velocity may also be possible by computations relating average wind velocity to the average migration rates of dunes. Field observations suggest that the dunes are most active during summer and autumn months. Wind velocity estimates derived from the Wyoming dunes should represent the strong summer winds rather than the extremely strong winter winds that sweep the area while the dunes are frozen. Conversely, blowouts with playa lakes are most active in the autumn and winter months (after spring runoff has evaporated). Thus, the playa lake blowouts should develop in response to the stronger autumn and winter winds. Length-to-width ratios of playas and playa plumes were tested as possible indicators of average wind velocities. The shape ratios of playas in the Northern Laramie Basin test area indicate a mature (very active) playa field (indicative of extremely strong winds), but correlations of shape ratios with other data have, so far, failed to yield quantitative estimates of mean wind velocities. The wind/landform relationships observed in each of the three test areas were employed in compiling a wind-energy prediction map for the southern Wyoming test region. This map shows the dominant patterns of windflow in the southern Wyoming wind corridor and the location of areas of extreme winds within the corridor. The map indicates areas of particularly high wind-energy potential and regions where special flow conditions persist. Mean wind velocity values obtained from permanent meteorological stations are plotted on the map for reference.

Data from airborne air-sensing probes reveal wave structures in the planetary boundary layer of the atmosphere in the wind corridor of south-central Wyoming. The airflow, which is nearly laminar throughout much of the region, responds in a series of resonant lee waves when it encounters topographic obstacles. Gravity waves and turbulent mixing are associated with a downward transport of vertical momentum and occur in the region of accelerated windflow in the central Wyoming wind corridor. Kelvin-Helmholtz waves are prevalent in the area of hydraulic jump at Windy Gap. Understanding of such waves and their controls is essential to siting of wind-energy systems in high-wind regions like the Wyoming wind corridor and in interpreting the mechanisms for development and migration of eolian landforms.

The Ferris Dune Field of south-central Wyoming lies in a topographically-regulated “corridor” of high wind that extends over much of southern Wyoming. Examination of geomorphology, sedimentology, and stratigraphy reveals that winds did not vary significantly in either average direction or speed during the Holocene period, but variations in precipitation, and hence plant growth, produced varying degrees of eolian activity. Deposition of dune sand resulted mainly from a decrease in the carrying capacity of the wind as it encountered the Ferris-Seminoe Mountain barrier. The Ferris dunes geomorphically resemble other dune fields in the western United States. Phytogenic dunes, varying in size and shape from small blowout dunes to large, well-developed parabolic dunes, dominate the landscape. A few actively migrating dunes occur both where the stabilized ground surface has been disturbed and where the highest wind speeds occur. Mineral analyses indicate that the Ferris dune sands were derived primarily from the Tertiary Battle Spring Formation. The Killpecker Dune Field “tail” sands and certain Cretaceous through Paleocene sandstones exposed along the Lost Soldier Divide were lesser contributors. The valley of Clear Creek reveals a relatively continuous Holocene section of interbedded dune and interdunal pond deposits. Bioturbated, low-angle (less than 15°) bedding, which characterized large portions of the eolian sands exposed there, attests to the long-term influence of vegetation and moisture on dune activity. Artifacts recovered in the vicinity of Clear Creek demonstrate Late Plains Archaic to Late Prehistoric occupations in this area. Radiocarbon dates from Clear Creek, comparison of Clear Creek chronology to other radiometrically-dated geologic-climatic events from the western United States, and theoretical dune migration rates reveal a general sequence of geologic-climatic events for the Ferris Dune Field: Eolian activity had begun in the Ferris-Lost Soldier area by at least ca. 9,950 to 10,330 years b.p. Major depositional intervals (indicating widespread Ferris dune activity) correlate with two radiocarbon-dated periods of drought. The first occurred between ca. 7,660 and 6,460 years b.p.; the second occurred following ca. 6,460 years b.p. (and lasted until ca. 5,500 years b.p.). Since the last major depositional (drought) interval, the climate in the Ferris-Lost Soldier area has moderated. Drought intervals have been short and vegetation has largely stabilized the dunes.