Rocks And Minerals

Question 1

Aureole

Answer 1

The zone of metamorphosed rock surrounding an igneous intrusion and showing the effects of contact metamorphism.

Question 2

Bowens reaction series

Answer 2

The sequence of minerals that form in the process of fractional crystallization of a magma.

Question 3

Burial metamorphism

Answer 3

A type of low-grade regional metamorphism affecting sediments and interlayered volcanic rocks that has lower temperatures (200- 450 degrees c) without any influence of orogenesis or magmatic intrusion.

Question 4

Color index

Answer 4

A number that represents the percent by weight or volume of dark-colored minerals in a rock

Question 5

Contact metamorphosm

Answer 5

Metamorphism associated with the intrusion of an igneous mass. Metamorphic changes are caused principally by heat, but also byag.a composition and eformation related to the intrusion. Pressures are relatively low (<3000 bars) while temp range from 200 to 1000 degrees c.

Question 6

Diagenesis

Answer 6

The physical and chemical changes undergone by sediments when compacted and lithified.