GLOSSARY - Chemical Fundamentals of Geology and Environmental Geoscience - page 247

GLOSSARY

α -emitter A radioactive nuclide that decays by emit-
ting α -particles. See Box 10.1.
α -particle (alpha particle, α ) See Box 10.1.
Absolute Measured from a fundamental zero-point,
e.g. 'absolute temperature'.
A b sorb, absorption Incorporation of a chemical spe-
cies into the interior volume of a solid substance (cf.
a d sorption ).
Accelerator mass spectrometry (AMS) An ultra-
sensitive mass spectrometer incorporating a parti-
cle accelerator, used to measure minute traces of
cosmogenic nuclides such as 14 C. See http://bit.
ly/1iWWzSt.
Acid, acidic See Appendix B and Box 8.1.
Accurate, accuracy Describes a measurement whose
systematic error is small.
Adiabatic Describes a process in which the system of
interest exchanges no heat with its surroundings.

A d sorb, adsorption Attachment of a chemical spe-
cies to the surface layer of a mineral or other solid (cf.
a b sorption ). See Box 8.2.
Aerosol A colloidal suspension of fine droplets or
particles dispersed in a gas (usually air). See Box 4.4.
Aliquot A representative fraction of a sample used
for chemical analysis.
Alkali, alkaline See Appendix B.
Allochromatic Colour of a crystal that is caused by
an impurity element (Gr. allos = other), e.g. the red
colour of ruby is due to the presence of Cr 3+ .
Aluminosilicate Chemical term for a class of silicate
mineral (e.g. albite, NaAlSi 3 O 8 = sodium alumino-
silicate) in which aluminium partially substitutes for
silicon in the tetrahedral ( network-forming ) sites in
the crystal structure (Figure 8.2 and Table 8.1).
Aluminium silicate A class of silicate minerals consist-
ing solely of aluminium, silicon and oxygen, including