Geologic Processes that Form Mineral Deposits

Surface Processes

Weathering - residual deposits

Soil

Clay

Laterite deposits

Iron, Aluminum, Nickel

Physical Sedimentation - rivers, beaches, dunes

Sand and Gravel

Placer deposits

Gold, Platinum, Diamonds, Ilmenite, Rutile, Zircon

Chemical Sedimentation

Evaporites

Halite, Sylvite, Borax, Trona

Limestone

Rock, cement, food and cosmetic additive

Hydrothermal Sediments

Iron, Manganese, Copper, Zinc, Silver, Gold

Organic Sedimentation

Coal, Oil, Natural Gas, Phosphate, Sulfur

Subsurface Processes

Oil

Maturation of organic matter, Migration of oil to traps

Hydrothermal-Veins, replacement bodies, disseminated ore

Ground water

Uranium, Vanadium

Basinal fluids

Brines, Lead-Zinc deposits

Seawater

Cu-Zn Massive Sulfide

Magmatic water

Porphyry Copper-Molybdenum,

Skarn (Pb, Zn, Cu, Ag, Au, W)

Metamorphic water

gold, copper

Magmatic Processes – Crystallization of Basalt magma chambers

Crystal Fractionation

Chromium, Vanadium, Titanium, Olivine

Immiscible sulfide liquids

Nickel, Copper, Cobalt, Platinum