2. Introduction
What is a mineral deposit? The gold deposits…
Is a sector of the cortex result of
different geological processes, Are mineralized geological
there has been the concentration bodies of which we can cost-
of one or more useful substances. effectively extract gold, the
same as found, usually as a
native metal, forming alloys
with copper, silver, osmium,
indium and other elements
in different proportions.
3. Different times of gold mineralization
• The geological history of the earth is marked by a
number of times of epigenetic gold mineralization,
most of which occurred in the Precambrian,
followed by other less extensive in the Paleozoic,
Mesozoic and Cenozoic. Most of placer gold has
occurred in the Tertiary and Quaternary.
4. Where does the gold found in the
deposits
Both gold and other minerals The origin of the gold deposits is
and elements that accompany
it come from the rocks that varied, but the main source is:
form the outer crust or melts HIDROTERMINAL
called magma coming from
RESIDUAL
deep within the earth's crust
that cooled and formed PLEASURES.
igneous rocks. These masses
magmatic bring gold and other
elements, which in optimal
conditions and favorable be
deposited in the vicinity of the
Earth's crust, forming ore
bodies of different shapes and
dimensions.
5. HIGH TEMPERATURE FIELDS HIDROTERMINALES
They are mainly linked with very old rocks (granitic and metamorphic
Precambrian and Paleozoic). The bodies are the most common mineral
veins or lodes of auriferous quartz, are less common in areas cuarcificación
or pyritization of schists, irregular shaped bodies or veins.
INTERMEDIATE TEMPERATURE FIELDS HIDROTERMINALES
These deposits, ore bodies are generally well defined veins, where gold is in
native form or within sulfides. Minerals conformantes of veins are quartz,
carbonates, barite, pyrite, chalcopyrite, sphalerite, galena, gray ores. Deposits
of this temperature are the most important, since it has the highest industrial
value.
HIDROTERMINALES FIELDS OF LOW TEMPERATURES
These are closely related alpine volcanic activity, and are in the form of
veins (stockwork and gold-mine argentífeiras) formed at shallow depths
within the volcanic rocks. The mineralization of these deposits is not
uniform, being bolsonadas rich and totally impoverished sectors.
Its mineralogical content is usually chalcedony, quartz, rhodochrosite,
barite, sulfides, minerals flat, essentially native gold-silver.
6. HIGH TEMPERATURE FIELDS HIDROTERMINALES
INTERMEDIATE TEMPERATURE FIELDS HIDROTERMINALES
Hidroterminales
Classification
according to
temperature
HIDROTERMINALES FIELDS OF LOW TEMPERATURES
7. Availability of solutions capable of dissolving
1 mineralizing and transporting mineral matter
Presence of openings in the rocks which
2 solutions can be channeled
KEY FACTORS FOR THE FORMATION Presence of placement locations for
OF HYDROTHERMAL DEPOSITS ARE: 3
deposition of mineral content
4 A chemical reaction resulting in the
deposition
5 Sufficient concentration of mineral matter
deposited to reach explotables make deposits.
8. RESIDUAL DEPOSITS
Gold are those that have occurred in the weathering of hydrothermal
deposits of sulfides. These areas are called "iron hat", where gold, as a
metal chemically stable and inactive, builds together with iron oxides,
carbonates of lead, silver and minerals other side, mainly stable oxides.
DEPOSITS OF PLEASURES
Be eluvial, alluvial and marine, of which the largest and most widespread
are alluvial placers. These deposits are formed due to the destruction of gold
deposits. By weathering processes. Then the larger gold particles are
deposited in alluvial deposits near the mine, whereas the finer particles are
carried down and deposited downstream together with the sands forming
auriferous alluvial sands.
9. What shape are the goldfields?
Stockworks Streaks or veins:
These tubular bodies where two of its
Are bodies irregular or
asymmetrically, where gold is found in dimensions are large enough along the
numerous intersecting veinlets or strike and dip, whereas third is very
disseminated form, usually of small relative to the other two, called
considerable size are bodies that are power.
mainly related to volcanic activity. The gold placers
Here gold is very unevenly distributed The gold placers are accumulations of
within the body forming bolsonadas sand usually are shaped like elongated
and sterile areas. halos that form in the course of rivers
or on the terraces adjacent to the river
also formed in marine beaches. Here
the gold occurs as disseminated in the
sand, usually in heavy mineral
fractions.
14. TYPES OF PLEASURES
En función de los distintos fenómenos fisco - químicos que los producen, los
placeres se clasifican en
Eluvial
Diluvial
Pro-alluvial
Alluvial
Beach
15. A. Eluvial pleasures are those which develop from one
area or pre-enriched enriched with environmental
component climate type. They dominated on the physical
chemical phenomena thus resulting effects are distinctly
residual.
B. If the material disintegrated, eluvial deposit if one
suffers a gravitational displacement, accumulating in some
points of a slope, will in a kind of pleasure called diluvial.
The origin of these pleasures have a chemical component
(eluvial) and a physical component (transport and partly
classification).
16. C. If the accumulations are located at the foot of the slope formed
pleasures are called pro-alluvial type and in them the physical
component (transporting and sorting) is greater than the chemical
component.
D. Clumps, or part of the pleasures eluvial, diluvial and / or pro-
alluvial, are remobilized, transported and sorted by
waters, and deposited in rivers (live bed), in its margins and / or
terraces, resulting pleasures are called alluvial
E. When the action of the ice to produce these pleasures are
referred moraine and fluvioglacial when the component is
mixed. In these pleasures the physical component is
predominant
