Geochronology

Question 1

A process unaffected by heat, pressure, fluids or chemical reaction

Answer 1

Radioactive decay

Question 2

the temperature below which a crystal lattice traps radioactive daughter products

Answer 2

Blocking or Closing temperature

Question 3

The most reliable technique of rocks wherein ages exceed 10 million years. The most common way of applying the U-Pb method to date a rock is by analyzing Zircon, Monazite and Sphene from crushed sample

Answer 3

Uranium-Lead method (U-Pb)

Question 4

Applicable in rocks aged that exceed 100 million years. The age is determined by analyzing 87 Rb, 87 Sr and 86 Sr in a mass spectometer.

Answer 4

Rubidium-Strontium method (Rb-Sr)

Question 5

Provides information primarily on the time of uplift of a rock mass because the relatively low blocking temperatures

Answer 5

Potassium-Argon method (K-Ar)

Question 6

Most commonly employed to provide a model age for the time separation of a Magma from the parent mantle and, in concern with Sr isotopes, data about sea water contamination and hydrothermal alteration of rocks

Answer 6

Samarium-Neodynium Method