Helping to resolve the shortage of domestic water supplies in arid and semi-arid lands largely focuses on groundwater resources. A large proportion of the Afro-Asian dryland belt is not well served by geological mapping at suitable scales, i.e. better than 1:250 000. The area is enormous and the number of trained Earth scientists falls far short of requirements for adequate, conventional field mapping. H2Oexplore is a free introductory course on the use of remote sensing and GIS technologies that address geology, terrain and hydrology, based on the widely used textbook Image Interpretation in Geology . Several case studies use a fully functional, free version of professional image processing and desktop mapping software. Geoscientists with access to a computer and the internet can independently study the standalone course in office or at home using a wide selection of exemplary data. The theoretical part of the course is provided here. The complete package is available on request as a free DVD (a small charge for production, packaging and postage is required in most cases), which includes the exercises, associated data, software and stereo anaglyph viewers.
Background theory is taught in six richly illustrated chapters. Chapter 1 covers the basics of hydrogeology. Chapter 2 is an introduction to remote sensing in the visible, reflected and emitted infrared, showing how the spectral properties of different surface materials can be used to design image processing and analysis strategies. Chapter 3 reviews the ‘traditional’ yet still highly effective use of stereoscopic aerial photography in terrain mapping and photogeology, using easily viewed stereo anaglyphs. Chapter 4 upgrades this approach to the wide-area stereo coverage available using ASTER data for several geologically well studied areas to demonstrate the relationships between terrain, rock types and structures in several study areas covered by published geological maps, and less well-known areas from NE Africa. Chapter 5 shows how the spectral approach introduced in Chapter 2 can be applied to multispectral Landsat and ASTER data, using various image processing strategies. It centres on a structurally complex area in central Eritrea that shows a wide variety of lithologies to demonstrate the mapping power of free Landsat and ASTER data. Chapter 6 covers digital analysis of topographic elevation data to extract accurate drainage networks useful in assessing surface water harvesting and aquifer recharge opportunities.
A series of practical exercises (DVD only) teach you how to use a free software package to interpret image and terrain-elevation data. The exercises cover the basic tools that you will need to produce digital geological maps: displaying and enhancing image data; detecting different minerals; terrain and hydrological analysis; and digital mapping. They are based on data sets from a wide variety of study areas intended to encourage users to develop skills and experience in water-resource reconnaissance. An Appendix guides you in acquiring and preparing globally available, free image data to use in the free software package. Subject to a limited but still useful image size (1000 x 1000 pixels or 30 x 30 km using Landsat or ASTER data). Completion and practice should give you the skills to undertake small, water-related projects independently anywhere in the Afro-Asian dryland belt to a professional standard.
The course is aimed at geoscience professionals in national surveys; independent consultants; senior geology undergraduates and engineers working in the WASH/WatHab sections of NGOs and international agencies.
 Drury SA (2001) Image Interpretation in Geology, (3rd edition): Nelson Thorne/Blackwell Science: London.
Note: To request a DVD of the whole course, please use the contact form below, remembering to include your postal address.