What are the stratiform ore deposit?
A final class of hydrothermal deposit is called stratiform because the ore minerals are always confined within specific strata and are distributed in a manner that resembles particles in a sedimentary rock. Because stratiform deposits so closely resemble sedimentary rocks, controversy surrounds their…
How are stratiform chromite deposits formed?
Stratiform deposits are formed as large sheet-like bodies, usually formed in layered mafic to ultramafic igneous complexes. This type of deposit is used to obtain 98% of the worldwide chromite reserves. Stratiform deposits are typically seen to be of Precambrian in age and are found in cratons.
How do I form an ore deposit?
Ore deposits formed by lateral secretion are formed by metamorphic reactions during shearing, which liberate mineral constituents such as quartz, sulfides, gold, carbonates, and oxides from deforming rocks, and focus these constituents into zones of reduced pressure or dilation such as faults.
How does residual ore deposit form?
RESIDUAL DEPOSITS IN GENERAL-The residual deposits are the insoluble products of rock weathering which have escaped distribution by transporting agencies, and which still mantle the rocks from which they have been derived. The rarer durable constituents of rocks, such minerals as zircon, rutile, garnet, tourmaline.
What is Podiform deposit?
Podiform chromite deposits are small magmatic chromite bodies formed in the ultramafic section of an ophiolite complex in the oceanic crust. These deposits have been found in midoceanic ridge, off- ridge, and suprasubduction tectonic settings.
What is sedimentary ore deposits?
Ore deposits form in sedimentary environments as a result of one of two generalised geological processes: either as a result of mineral precipitation from solution in surface waters, most commonly from sea water or lake waters; or as a result of physical accumulation of ore minerals during processes of sediment …
What is the difference between stratiform and stratabound?
Stratabound ore deposits are more easily discussed if the concepts of strata and strati- form are clear. Stratabound and stratiform deposits are closely related; in fact stratiform deposits are always stratabound although the reverse is not true.
What is stratabound?
Said of a mineral deposit confined to a single stratigraphic unit. The term can refer to a stratiform deposit, to variously oriented orebodies contained within the unit, or to a deposit containing veinlets and alteration zones that may or may not be strictly conformable with bedding. Ref: AGI.
What are ore deposits called?
Certain kinds of mineral can be smelted more readily than others; these are commonly referred to as ore minerals. Ore minerals tend to be concentrated in small, localized rock masses that form as a result of special geologic processes, and such local concentrations are called mineral deposits.
What is residual ore deposit?
An accumulation of valuable minerals, formed by the natural removal of undesired constituents of rocks or conversion of useless to useful components.
Where are residual deposits found?
residues from dissolution are called residual deposits. They occur most prominently in warm tropical regions subjected to high rainfall.
How is the composition of stratiform deposits determined?
In stratiform deposits, there is a predominance of stratified bodies that are conformable with the enclosing rocks. The ores in these bodies have simple mineral compositions determined by the dissemination of copper, zinc, and lead sulfides and the accompanying minerals in one or more strata of the ore-bearing rocks.
What kind of ore is a strataboundore deposit?
deposits are referred to as stratiform. Strataboundore deposits are any type of orebodies, concordant or discordant, which are restricted to a particular
Where are stratiform rocks found in the world?
Granites intruded during the late stages of rifting are often associated with Sr and fluorite. Stratiform Cu deposits occur in rift-related shales and sandstones as exemplified by deposits in the Zambian Copper Belt, where the Cu appears to be derived from associated basalts.
Are there Mag Matic rocks in stratiform deposits?
This hypothesis, however, is contradicted by the absence of mag-matic rocks in the areas where the stratiform deposits are found.