Describes the groundwater fluid body constituents and their relationships. OGC WaterML 2.2 Part 4 - GroundWaterML 2 is an OGC Standard. Copyright (c) 2016 Open Geospatial Consortium. To obtain additional rights of use, visit http://www.opengeospatial.org/legal/ . Characterisation of the chemical composition of the fluid body, both natural and man-made. Chemical component type, e.g. arsenic. Characterisation of the biological composition of the fluid body, both natural and man-made. #NOTES Biological species. General (abstract) entity denoting a material, chemical or biological constituent of a fluid body. The physical state of the constituent, i.e. solid, liquid, or gas. Relates to constituents composing another constituent Relates to the constituent which a constituent is part of The physical state of the constituent, i.e. solid, liquid, or gas. The physical state of the constituent, i.e. solid, liquid, or gas. A gas is a compressible fluid. Not only will a gas conform to the shape of its container but it will also expand to fill the container. (wikipedia) A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. (Wikipedia) In a solid the particles (ions, atoms or molecules) are closely packed together. The forces between particles are strong so that the particles cannot move freely but can only vibrate (wikipedia) Suspended or colloidal material in a fluid body, e.g sediment. Name of the suspended or colloid material in the fluid body, e.g. a lithology or mineral name. Relation between fluid body components, typically caused by a specific mechanism, e.g. coating (from adsorption), constitution (from chemical bonding forming a new material), aggregation (from physical bonding, e.g. pressure), containment (from absorption, digestion). Type of relation between fluid body components, typically caused by a specific mechanism, e.g. coating (from adsorption), constitution (from chemical bonding forming a new material), aggregation (from physical bonding, e.g. pressure), containment (from absorption, digestion). Mechanisms by which materials (of various states) come into a relationship, e.g. sorption, precipitation, digestion, excretion, etc. Relates to the constituent which a constituent is part of Relates to constituents composing another constituent Name of the mineral (eg: orthoclase) or mineral family (eg: feldspar), approved by the International Mineralogical Association. (eg: http://www.mindat.org/mineralindex.php) A controlled concept indicating the name of the RockMaterial type (eg, quartz sandstone, basalt, muscovite schist, sand, mud, soil, saprolite). Igneous rock definitions are governed by IUGS agreed vocabulary