1. Epithermal gold ore deposits
Professor: Dr Alireza Bavand Pur
Author: Pouria Salami
Academic year:

2. Content: Introduction……………………………………3
Types of epithermal gold deposits…………....4
Types of epithermal sulphidation …………6
Geological setting……………………………..8
Other Property………………………………..11
Reference…………………………………….14

3. Introduction:
Epithermal mineralization usually at 50 to 200 ° C at the surface and depth of 1000 meters are formed.
Groundwater and magma have a fundamental role in this process.

4. Generally Epithermal gold deposits are found in three types:
1. Scattered in carbonate rocks (type carbonate)
2. Scattered volcanic rocks (the type of hot water springs)
3. Type of vein
Epitheram gold deposits based on alteration and mineralogy divided into two groups:
1: High sulfide: 10 to 90% by volume is sulfide.
2. Low sulfide: 1 to20 % by volume is sulfide.

5. Types of epithermal gold deposits

6. Two types of epithermal sulphidation gold deposits have been identified
1- Au/Ag
The average storage: 0.77 million tons, average grade: 1 g/t
2.Au/Cu
The average storage: 0.3 million tons, average grade: 0.3 g/t

7. Types of epithermal sulphidation

8. Geological setting
Epithermal gold deposits are found with acid pyroclastic rocks and the calc-alkaline medium, which is made out of water.
Related volcanic rocks:
Andesite and rhyolite
Associated Minerals:
Minerals deposit can be economically are:
Sylvanite (Au, AgTe2 )
Petzite (Au, Ag2Te )

9. Argillic, sericitic, alunitic, propylitic
We can see these alteration in this mineralization:
Argillic, sericitic, alunitic, propylitic
Texture epithermal minerals are:
1.Filling empty spaces
2. Dissemination like: carbonate and tuff rocks
3.Stock works
The structure of epithermal deposits more are:
Vein and scattered particles.

10. Geological setting

11. Other Property Tectonic setting: Epithermal gold deposits resources:
The island arc and continental margin found.
Epithermal gold deposits resources:
High sulfide: small reserve
Low sulfide: big reserve
Geochemical Features:
High sulfide: high copper and low Ag/Au
Low sulfide: high zinc, lead and high Ag/Au

12. Other property

13. Reference: 1. www.Usgs.com 2. www.Gsi.ir
3.Economic geology, Shahab poor, Jamshid, Shahid Bahonar University.2001
4. Geoscience Database of Iran.