摘要：The source of fluids in the continental crust is variable (i.e. atmo- sphere, earth surface, continental crust, slab, mantle). Fluids, liquid and gas/vapor, can be meteoric, formational (cognate, basinal), hy- drothermal, magmatic and metamorphic. Temperature, pressure, composition, and concentration of fluids govern fluid-rock interac- tion. Because of physical properties of fluids (i.e., low cohesive forces due to weak inter-molecule attraction forces; practically null restitution forces) they are able to freely move and to easily change their form, and they lack yield strength. In fluids, stress is a function of the strain rate: they can resist normal, but cannot sus- tain shear-stress because they respond to shear stress with motion. The resistance of fluids to move is related to fluid viscosity. Fluid molecules can separate from each others in gases and vapors, but they do not in liquids because liquids do not fill a volume by expanding into it. Consequently, gases are compressible and, in general, liquids are incompressible.
