HYDROTHERMAL ALTERATION

the hydrotermal fluids are mostly of magmatic origin furthermore these contains

metals. These metals are deposit a diferent conditions phisical and chemical ,when the

magma has high pressure and temperature, its has hight solubility on the contrary ,if

it has low pressure and temperature, it will has low solubility.

the first boiling occurs When the magma lose solubility and the wather is part , la

second boiling occurs when the magma crystallizes so that this results from the

exsolution of water.

The Hydrothermal phase comprises a vapor phase and a saline hidrosalmuera ,the

hidrosalmuera is containing Na and Cl. the metals for example the Cu , Zn, Pb , Au, Ag

between other have been incorporating the phase crystalline in rock-forming minerals

The hydrothermal alteration is the product of a process of exchange chemical between

the host rock and hydrothermal fluids because they interact so that this interaction is

going to change the properties chemical and mineralogical in the rock as well as in the

fluids hydrothermal

in the nature are recognize several types of hydrothermal alteration .it can

characterize for the association of ore specific nevertheless the hydrothermal

alteration is dependent of the various factors so we have : hydrothermal fluid’s

composition, host rock’s composition , temperature, ph(Hydrogen potential), eh , the

relation between the water and the rock and interaction’s time.

some changes are summarized have been summarizing in diagrams such AKFC (rose

and burt, 1979) as well as cobert and leach (1998) and Meyer and Hemley

the process can be Depositación directa, hydrolysis,

The stability of feldspars, micas and clays of hydrothermal alteration processes is

controlled by hydrolysis, in which K +, Na +, Ca2 +, and other cations ore transferred

to the solution and the H + has been incorporating into the solid phases remaining.

This has been denominating hydrogen metasomatismo (Hemley and Jones, 1964).

Nevertheless Hydrolysis reactions are very important in the processes of change

hydrothermal

So we have : potasic alteration, propylitic alteration ,albitacion, quartz sericite

alteration,moderate and advanced argillic alteration ,carbonate alteration, alteration

calcosilicatada between other

alteraciones hidrotermales

la alteración hidrotermal es el producto de un proceso de intercambio químico entre la

roca huésped y el fluido hidrotermal debido a que interactúan de modo que esta

interacción se va a cambiar las propiedades químicas y mineralógicas en la roca, así

como en los fluidos hidrotermales

en la naturaleza se reconocen varios tipos de la alteración hidrotermal se

puede caracterizar por la asociación de minerales específicos, sin embargo la

alteración hidrotermal depende de los diversos factores por lo que tenemos:.

composición del fluido hidrotermal, la composición de la roca huésped, la

temperatura, el pH (potencial de hidrógeno) , eh, la relación entre el agua y la

roca y el tiempo de interacción.