Types Cycle Aging Dating Rocks 100 200 300 400 500

What are the three types of rocks? 1.1

Igneous, Sedimentary, and Metamorphic

How would a glassy igneous rock form? 1.2

Quick cooling / extrusive

What determines the grain size of an igneous rock? 1.3

The slower the rock took to cool, the coarser (larger) the grain.

What kind of rock is made from solutions of dissolved minerals in water? 1.4

Chemical Sedimentary

What are the two classifications for metamorphic rock? 1.5

non-foliated (no folds) foliated and non-foliated (no folds)

What is the process by which sediment is dropped and comes to rest? 2.1

deposition deposition

What is needed to form metamorphic rock? 2.2

heat and pressure

How are igneous rocks formed? 2.3

by magma cooling and crystallizing

What is the first step to becoming a sedimentary rock? 2.4

weathering

List, in order, four steps to forming sedimentary rock 2.5

uplift and exposure, weathering, erosion (transportation), deposition, compaction, cementation, (lithification)

What is the term for when the order of geologic events has been established, but no exact date has been determined? 3.1

Relative Date

Sequence B, G, E, and F from oldest to youngest. 3.2 G, B, E, F Sequence B, G, E, and F from oldest to youngest.

G, B, E, F

What are cross-cutting relationships? 3.3

an intrusion or fault is younger than the rock it cuts through

Describe uniformitarianism. 3.4

the processes we observe today are the same processes that happened millions or billions of years ago

List 3 of the 5 geological “rules” or principles used to place geologic events in order. 3.5

original horizonality, inclusions, cross-cutting relationships, superposition, original horizonality, inclusions, cross-cutting relationships, uniformitarianism

What is the term used when the exact age of a rock has been determined? 4.1

Absolute Age

Measuring the age of an object based upon the ratio of parent isotope to daughter decay product is? 4.2

Radiometric Dating

What is half-life? 4.3

The amount of time it takes for half of the radioactive material in an object to decay into the next stage

If a sample started out with 60 radioactive isotopes, how many radioactive and how many stable daughter atoms would be present after 2 half-lives? 4.4

15 radioactive 45 stable daughter atoms

In what type of rock would you most likely find fossils? 4.5

Sedimentary

What type of rock is sandstone? 5.1

sedimentary

What is the classification of limestone (both the type and its subtype)? 5.2

organic sedimentary

What rock does granite metamorph into? 5.3

Gneiss

What rock does marble come from? 5.4

limestone

What are the three processes that form metamorphic rocks? contact, ? and ? 5.5

contact, hydrothermal, and regional