Richard36
Well-known member
By reading the landscape it is possible to locate enriched areas of economic minerals.
These enriched areas are always in a zone that has gone through some grade of Hydrothermal alteration,
Which is the process of magmattic gasses mixing with the water present within the melt to create acidic solutions that dissolve all metallic, and nonmetallic minerals at depth, and redeposit them close to the surface by precipitating out from solution as the pressure and temperature decreases. Oxides form toward the end of the cooling cycle, and sulfides form early while water is still present.
Indicator minerals to look for will be those that have a melting point + or - 500F of the melting point of gold, if hunting gold, or of platinum, if you are hunting Pt.
With that being said,
Stream drainage patterns are directly related to the underlying rock of any given region, and reflect the type of geologic activity that took place there in the disstant past.
I will focus on one.
That pattern is the "Dendritic Stream/River Drainage Pattern".
Here are a few photo's.
These river drainage patterns are associated with compression created by folliation in the mountain building process, as is the case with the Cascade and Rocky Mountain Ranges.
These ranges were created by Uplift, and Compression as the Continental Plate slid over the Oceanic Plate.
This process generates great heat at depth which melts all material Subducted as it gets close to the Upper Mantle.
This Crustal Material is a wet material full of water.
This water is converted to steam, which then combines with the gasses within the melt to create various acids that dissolve all minerals within the melting Crustal Material, and the overlying rock as it makes its way to the surface, which redeposits its mineral load as it makes its way upward as stated earlier.
This Meteoric Water is also necessary for the magma to differentiate into the various Rock Types, Which are the Host Rock(S) for the various minerals, some of which are magmatic, forming within the melt itself, while others form from Hydrothermal solutions Created by the pressence of water within the melt.
I will focus on those minerals created by Hydrothermal solutions.
These minerals are often associated with Granitic Rocks, and differentiation products thereof, because the intruding maggma supplies the heat, and the water necessary for overlying enriched deposits to have formed.
These Granitic Rocks are offten associated with Dendritic Stream Drainage Patterns, and therefore can be found simply by looking at a Topographic Map of the area that you intend to prospect.
Pick areas with a Dendritic Drainage Pattern, and you will be in the correct zone to find Economicly Feasable Deposits of Metallic, and NonMetallic Minerals.
The remaider of this page is dedicated to Hard Rock Ores.
Page 2 Starts the explanation regarding locating, and working Various Placer Deposits.
Here are a few photo's of Granite, and related Field Structures to Look in.
These enriched areas are always in a zone that has gone through some grade of Hydrothermal alteration,
Which is the process of magmattic gasses mixing with the water present within the melt to create acidic solutions that dissolve all metallic, and nonmetallic minerals at depth, and redeposit them close to the surface by precipitating out from solution as the pressure and temperature decreases. Oxides form toward the end of the cooling cycle, and sulfides form early while water is still present.
Indicator minerals to look for will be those that have a melting point + or - 500F of the melting point of gold, if hunting gold, or of platinum, if you are hunting Pt.
With that being said,
Stream drainage patterns are directly related to the underlying rock of any given region, and reflect the type of geologic activity that took place there in the disstant past.
I will focus on one.
That pattern is the "Dendritic Stream/River Drainage Pattern".
Here are a few photo's.
These river drainage patterns are associated with compression created by folliation in the mountain building process, as is the case with the Cascade and Rocky Mountain Ranges.
These ranges were created by Uplift, and Compression as the Continental Plate slid over the Oceanic Plate.
This process generates great heat at depth which melts all material Subducted as it gets close to the Upper Mantle.
This Crustal Material is a wet material full of water.
This water is converted to steam, which then combines with the gasses within the melt to create various acids that dissolve all minerals within the melting Crustal Material, and the overlying rock as it makes its way to the surface, which redeposits its mineral load as it makes its way upward as stated earlier.
This Meteoric Water is also necessary for the magma to differentiate into the various Rock Types, Which are the Host Rock(S) for the various minerals, some of which are magmatic, forming within the melt itself, while others form from Hydrothermal solutions Created by the pressence of water within the melt.
I will focus on those minerals created by Hydrothermal solutions.
These minerals are often associated with Granitic Rocks, and differentiation products thereof, because the intruding maggma supplies the heat, and the water necessary for overlying enriched deposits to have formed.
These Granitic Rocks are offten associated with Dendritic Stream Drainage Patterns, and therefore can be found simply by looking at a Topographic Map of the area that you intend to prospect.
Pick areas with a Dendritic Drainage Pattern, and you will be in the correct zone to find Economicly Feasable Deposits of Metallic, and NonMetallic Minerals.
The remaider of this page is dedicated to Hard Rock Ores.
Page 2 Starts the explanation regarding locating, and working Various Placer Deposits.
Here are a few photo's of Granite, and related Field Structures to Look in.
