A Study Of Global Sand Seas

Early descriptions and considerations of the characteristics of modern eolian sand deposits, mostly in the great sand seas of the world, date back to the 1880's and 1890's, when pioneer geologists and explorers wrote their classic papers on desert dunes. One or two decades later, interest in eolian processes greatly increased when wind-formed deposits were recognized in ancient sandstones in many parts of the world and in rocks of many ages. Throughout the 20th century, as the science of geology has expanded and the programs of the U.S. Geological Survey have proliferated to keep pace, dune studies have had a similar growth. Work was initially concentrated mostly on the description of dune forms or morphology and on analysis of textural features; by midcentury, however, major contributions had been made to the physics of eolian sand by detailed studies and interpretations of minor eolian structures, by statistical analyses of cross-strata dip directions, and by the development of systems for dune classification. Most recently, interest has been renewed in detailed grain studies, in the study of cross-strata, and in interpretation of dune patterns by means of aerial photographs and Landsat imagery. A major feature of this report on global sand seas is the compilation and comparison of available data based on many different methods of investigation. The application of these studies to economic problems, which is described in one chapter, clearly illustrates the importance of eolian deposits to our present culture and to human welfare. H. William MenardDirector, U.S. Geological Survey

Papers cover the entire spectrum of eolian investigations, ranging from the microscopic level to regional synthesis as well as ancient eolian deposits and their interpretation.

Volume 2 of the book ‘Sand Dunes of the Northern Hemisphere’ is sub-titled Characteristics, Dynamics and Provenance of Sand Dunes in the Northern Hemisphere. It brings together a vast body of information and insight into sand dune and desert systems from North Asia, Central Asia, North Africa and the Middle East. Chapters from the Russian Federation include studies on dune systems within the permafrost zone and there is a case study from temperate zone dune system in coastal Japan. Volume 2: Characteristics, Dynamics and Provenance of Sand Dunes in the Northern Hemisphere of 16 chapters in three Parts, focusses on Saharan Africa, Egypt, and Middle East and gives attention to sand mobility and encroachment with case studies from a number of countries where these matters are of concern. We also include chapters on the remote dunes in the permafrost zone and in the hyper-arid deserts of Iran. Case studies are used to highlight the characteristics of dunes and their interaction with humans in several widely divergent settings. Volume 2 concludes with some musing on the value of study of the past as key to the future and speculates on what the future might hold in the light of a warmer and drier Earth and a rise in sea level that threaten large tracts of low-lying land with marine incursions and destruction from storm surge. PART 4 Sand Mobility and Encroachment The seven chapters in this Part examine the real-world impact of sand encroachment and dune migration on people and their economic activities and the health, welfare and financial implications related to destruction of infrastructure, including human habitations. PART 5 Sand Dune Landscapes Distribution, Formation and Management Seven Case studies from several geographic regions in Africa, the Middle East, north-east Asia are presented here to demonstrate the underlying mechanisms in dune formation and the diverse approaches to their management. Human impacts such as sand mining, tourism development, combine with natural forces like climate variability to challenge the realization of an optimum management strategy. PART 6 Concluding Thoughts: Coping with an Unknown Future from a Little-known Past The two chapters in Part 6 have special roles. We are privileged to publish new research findings that are summarized here in Chapter 38 from extensive and detailed work conducted in the Kyzyl Kum, and Karakum sand seas of Central Asia. There is a strong belief that further study of the little-known past such as revealed in this study could unlock clues as to what a future Earth might look like. This leads on to speculation in Chapter 39 about the implications of what we already know about global change (not only climate change) and the impact of the Anthropocene on the dune systems, both inland and coastal. Sea level rise, marine incursions and an increase in extreme weather events will affect dune systems and sand seas on the Northern Hemisphere (and beyond).

The Great Sand Sea in Egypt presents the history of one of the large sand seas in the Sahara, beginning with the sand supply by fluvial transport from partly distant areas and also by local sandstone weathering. It also details sand as carrier of information and shows the possibilities of sedimentary analysis in dealing with such a topic. Simple measurements may supply important information (e.g. salinity measurements). Well known methods can be developed further to answer special questions. A wealth of information can be drawn from especially adapted sedimentological investigations. In the end, bits of information from different analytical sources can be put together to reveal the history of a large sand sea. *Analyzes different geological sources to decipher the history of the Great Sand Sea *Presents the possibilities of sedimentary analysis to interpret the history of an area *Develops well-known methods to further answer special questions

A collection of extended abstracts of papers presented at two workshops on the title subject.