Week 2 Flashcards
Magmatic differentiation
the process that different igneous rocks, like basalt and granite, go through chemically to form the same initial magma
done two ways: assimilation and fractionation
Hydrothermal fluids
hot, aqueous solutions; some transport and deposit ore materials
Pegmatities
very coarse-grained igneous rocks; sometimes have accumulations of rare earth elements
Copper-porphyry deposits
copper ore bodies formed by hydrothermal fluids which originate from a magma chamber several km below the deposit
Massive sulfide deposits
volcanic ore deposits; mostly copper-zinc which are associated with and created by volcanic hydrothermal events in submarine environments
Placer
surficial mineral deposit formed by mechanical concentration of mineral particles from weathered debris
Skarn
an assembly of lime-bearing silicates derived from limestones and dolomites by the introduction of silicon, iron, and magnesium; usually adjacent to an igneous intrusion
Laterite
a highly leached soil zone in tropical regions that’s rich in iron oxides
Evaporite
sedimentary rocks that form as a result of the evaporation of saline solutions
Diagenesis
physical and chemical changes that occur in a sediment after deposition, and during/after lithification but not during weather and metamorphism
Mississippi Valley type
a term applied to a class of mineral deposits widespread in the drainage basin of the Mississippi River; zinc and/or lead sulfide ores that occur in carbonate rocks
(ferro) Manganese nodules
rounded, concentrically laminated masses of iron and manganese oxides and hydroxides that form on the floors of oceans and some lakes
Black smoker
a sea floor vent issuing hot fluids, which on mixing with seawater they precipitate very fine-grained sulfide minerals that look like black smoke
