GEOLOGICAL CONSERVATION 29 analytical techniques and quality control of the data were not always given full consideration in early surveys, but are now mandatory where comparisons are to be made on a global basis Just as the mobile component of elements has been found to be most useful for identifying mineral deposits, for environmental surveys, emphasis must be given to measuring the fraction of the element that is bioavailable Thus, selective leaches are used and, where waters are sampled, speciation calculations can be made to estimate the amounts of potentially toxic elements that are bioavailable See Also Environmental Geochemistry Gold Igneous Rocks: Kimberlite Minerals: Sulphides Mining Geology: Exploration Sedimentary Processes: Glaciers Soils: Modern Further Reading Brooks RR (1983) Biological Methods of Prospecting for Minerals New York: Harper and Row Cameron EM, Hamilton SM, Leybourne MI, Hall GEM, and McClenaghan BE (2004) Finding deeply buried de posits using geochemistry Geochemistry: Exploration, Environment, Analysis 4: 26 Carrigan CR, Heinle RA, Hudson GB, Nitao JJ, and Zucca JJ (1996) Trace gas emissions on geological faults as indicators of underground nuclear testing Nature 382: 528 531 Griffin WL (1995) Diamond exploration into the 21st century Journal of Geochemical Exploration 53: 367 Gurney J and Zweistra P (1995) The interpretation of major element compositions of mantle minerals in diamond exploration Journal of Geochemical Exploration 53: 293 309 Hale M and Plant JA (eds.) (1994) Drainage Geochemistry Amsterdam: Elsevier Hall GEM (1998) Analytical perspectives on trace element species of interest in exploration Journal of Geochemical Exploration 61: 20 Maurice YT, Dyck W, and Strnad JG (1985) Secondary dispersion around the uranium nickel deposit at Key Lake, northern Saskatchewan In: Sibbald TII and Petruk W (eds.) Geology of Uranium Deposits Can adian Institute of Mining Metallurgy Special Volume, pp 38 47 Montreal: Canadian Institute of Mining, Metallurgy and Petroleum Plant J, Smith D, Smith B, and Williams L (2000) Environ mental geochemistry at the global scale Journal of the Geological Society, London 157: 837 849 Rose AW, Hawkes HE, and Webb JS (1979) Geochemistry in Mineral Exploration London: Academic Press Zeegers H and Butt CRM (eds.) (1992) Regolith Explor ation Geochemistry in Tropical and Subtropical Terrains Amsterdam: Elsevier GEOLOGICAL CONSERVATION J E Gordon, Scottish Natural Heritage, Edinburgh, UK ß 2005, Elsevier Ltd All Rights Reserved Introduction The long and varied geological history of planet Earth is reflected in the great diversity of its rocks, minerals, fossils, landforms, soils, and active geomorphological processes In many parts of the world this diversity is under threat from a range of human activities Traditionally, geological conservation has involved the protection, management, and interpretation of specific sites, or ‘monuments’, recognized to be of national or international importance on scientific grounds because of their geological and geomorphological features More recently, a broader approach has centred on the idea of ‘Earth heritage’ (Earth heritage conservation) and latterly on the concept of ‘geodiversity’ (geoconservation) Geodiversity is the variety of geological environments, rocks, minerals, fossils, landforms, unconsolidated deposits, soils, and active geomorphological processes in a defined area Geodiversity provides the foundation for life on Earth and for the diversity of natural habitats and landscapes, as well as for many aspects of cultural landscapes and built environments It is therefore a valuable environmental, scientific, educational, cultural, and economic resource It is now increasingly recognized that proper conservation management of the non-living parts of the natural world is crucial for sustaining living species and their habitats This leads to a broader role for geological conservation, incorporating not only the protection of geological and geomorphological features of scientific and educational value but also the management of natural environments and processes that support habitats and species Such a role requires more integrated approaches to nature conservation and the management of sites and landscapes, which recognize the dependencies between biodiversity and geodiversity It also embraces the involvement of people and society and their