ORE DEPOSITS
by MARUN OLDENBURG
1. CLASSIFICATION AND TYPES OF MINERAL DEPOSITS
1.1. • COMMODITY BEING MINED
1.2. • TECTONIC SETTING IN WHICH THE DEPOSIT OCCURS
1.3. • GEOLOGICAL SETTING OF THE MINERAL DEPOSIT
1.4. • GENETIC MODEL FOR THE ORIGIN OF THE ORE DEPOSIT
2. EVAPORITE DEPOSITS
2.1. AN EVAPORITE IS A SEDIMENT THAT FORMS THROUGH THE EVAPORATION OF SALINE WATER. THE MOST COMMON EVAPORITE DEPOSITS ARE SALTS (MOST COMMONLY SYLVITE AND HALITE), GYPSUM, AND NITRATES.
3. THERE ARE:
3.1. METALLIC DEPOSITS
3.2. NON-METALLIC DEPOSITS
3.3. FOSSIL DEPOSITS
4. PLACER DEPOSITS
4.1. THESE ARE MADE OF ALLUVIAL, COLLUVIAL AND ELUVIAL MATERIAL
5. OXIDISED ZONES OF ORE DEPOSITS
5.1. THE REGION ABOVE THE WATER-TABLE IN AN ORE DEPOSIT IS KNOWN AS THE OXIDISED ZONE AS IT IS THE ZONE OF OXIDATION OF THE PRIMARY ORE MINERALS.
6. PHOSPHATIC DEPOSITS
6.1. PHOSPHORITE IS A COMMONLY USED TERM FOR LITHIFIED PHOSPHATE ROCK. THE ISLAND OF NAURU IN THE PACIFIC IS ONE OF THE WORLD'S LARGEST DEPOSITS OF PHOSPHORITE AND HAS BEEN MINED SINCE AT LEAST THE 1950S.
7. ORGANIC DEPOSITS
7.1. COAL
7.1.1. IS A GENERAL NAME GIVEN TO STRATIFIED ACCUMULATIONS OF CARBONACEOUS MATERIAL DERIVED FROM VEGETATION
7.2. FIRECLAY
7.2.1. IS A FOSSIL CLAY-RICH SOIL ASSOCIATED WITH COAL DEPOSITS. IT IS USEFUL AS A REFRACTORY MATERIAL.
7.3. PEAT
7.3.1. IS A PARTIALLY DECOMPOSED MASS OF VEGETATION THAT HAS GROWN IN A SHALLOW LAKE OR MARSH.
7.4. OIL/PETROLEUM
7.4.1. NATURAL DEPOSITS OF OIL ARE MOST COMMONLY FOUND ASSOCIATED WITH NATURAL GAS (WHICH IS ITSELF DERIVED FROM THE HEATING-UP OF THE OIL), SALT WATER, AND SOMETIMES, SOLID HYDROCARBONS.