Abundance of the chemical elements in the Sun and outer planets is similar to that in the universe. Due to solar heating, the elements of Earth and the inner rocky planets of the Solar System have undergone an additional depletion of volatile hydrogen, helium, neon, nitrogen, and carbon (which volatilizes as methane). The crust, mantle, and core of the Earth show evidence of chemical segregation plus some sequestration by density. Lighter silicates of aluminum are found in the crust, with more magnesium silicate in the mantle, while metallic iron and nickel compose the core. The abundance of elements in specialized environments, such as atmospheres, or
International Association for Engineering Geology and the Environment large projects and in the assessment and remediation of environmental issues, an update of the first statutes of the association was deemed necessary. The second statutes were approved by the general assembly in Kyoto (Japan) in 1992. A new definition of engineering geology was given, which reflected the experience collected during the previous 25 years and read as follows: "“Engineering geology is a science devoted to the investigation, study and solution of engineering and environmental problems which may arise as the result of the interaction between geology and the works and activities of man as well as to the prediction