Earth Sciences 4432A/B Lecture Notes - Lecture 3: Overburden Pressure, Geothermobarometry, Fluid Inclusions
13 Apr 2016
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Document Summary
As the names imply, geothermometry and geobarometry are the measurements of temperature and pressure of minerals, rocks and fluids in the earth. Temperature and pressure are two of the most important parameters that control metal solubilities in magmas and fluids, consequently knowledge of t and p is fundamental to the understanding of ore genesis. Fluid inclusions are extensively used for this purpose and will be discussed in a later lecture. However, even fluid inclusions usually require an independent estimate of t to obtain p or of p to obtain t. there are several different approaches to estimate t and p. A common geological constraint used in geobarometry is that of stratigraphic reconstruction. If the depth of mineralization can be established, then the pressure of mineralization can be constrained, by assuming either lithostatic or hydrostatic conditions: P = gh where p is pressure, is density, g is the gravitational constant (9. 8 m/sec2) and h is height (or depth).
