Economic Geology Part 2

Question 1

What are disseminated hydrothermal ore deposits

Answer 1

Mineral is distributed through rock body, rather than concentrated in veins

Question 2

Describe Vocanogenic Massive Sulphide (VMS)

Answer 2

deposits are lenses of sulphide material that accumulate on the seafloor from hydrothermal events

Question 3

What are black smokers?

Answer 3

Heater seawater rich in dissolved metals vented from seafloor

Question 4

What are sedimentary exhalative deposits?

Answer 4

• Massive sulphide deposits formed from
seafloor hydrothermal vents in sedimentary
basins

Question 5

Sediment-Hosted Stratiform Copper

Answer 5

Oxidized copper-bearing brines moving through coarse-grained
sedimentary rock are forced upward into reduced sediments, which
promotes the precipitation of sulphide minerals

Question 6

Unconformity-Associated Uranium

Answer 6

Oxidized uranium-bearing brines moving through coarse-grained
sedimentary rock are forced upward into reduced sediments, which
promotes the precipitation of reduced uranium minerals

Question 7

Define Placer deposits

Answer 7

formed when heavy metals are

mechanically concentrated by currents in rivers

Question 8

Define residual enrichment

Answer 8

concentrating metals into economically valuable concentrations

Question 9

What is the principle ore of aluminum

Answer 9

bauxite

Question 10

What is laterite, and where is it formed?

Answer 10

(enriched in Fe, Al, Ni) forms by deep weathering of

the parent rock and leaching out elements such as silica

Question 11

What rare, ultramaific rocks are diamonds found in?

Answer 11

kimberlites