Geology 101 Introduction to Geology for the

Christian Leaders Grand Canyon Trip

1. How do we do science?

Brand, L. 1997. Faith Reason and Earth History. Andrews University Press, Berrien Springs, MI. Brand, L. 2006. A Biblical perspective on the philosophy of science. Origins, no. 59, p. 6-42.

For Further Reading:

The “Conventional” view of earth history

The Creation Geology view of earth history

“Precambrian”

Paleozoic

Mesozoic

Cenozoic

Years before present

~6,000

~4,344

~4,343

Today Today

66 million

245 million

542 million

4,600 million

Time Periods of Earth History

The Great Unconformity

Cambrian Period

Bacteria were the only life forms during this time. No

other fossils.

These rocks represent Creation Week & Pre-Flood rocks. Conditions for fossilization not generally present.

Rocks made during Noah’s Flood

Post-Flood Rocks

Trilobites, marine fossils, coal

Dinosaurs

Mammals The Ice Age

See Garner, 2008, Time for an upgrade?, Answers Magazine, v.

4, p. 49.

TIM

E

“Precambrian”

Paleozoic

Mesozoic

Cenozoic

Years before present

~6,000

~4,344

~4,343

Today

4,600 million

Time Periods of Earth History

The Great Unconformity

Cambrian Period

Rocks made during Noah’s Flood

Post-Flood Rocks The Ice Age

Grand Canyon Rocks

2. Rocks & Minerals

Minerals Rocks are made of one

or more minerals

3. The Three Main Types of Rocks

Sedimentary Shale Sandstone Limestone

Igneous Granite Basalt Diabase

Metamorphic Schist Gneiss Marble

Igneous Metamorphic

Sedimentary

Rocks made of crystals

Rocks made of little pieces of other rocks

Sedimentary Rocks

Lots of layers, water-laid Only kind of rocks to

contain fossils

Clastic Conglomerate, Sandstone,

Siltstone, Shale

Chemical Rock salt, travertine limestone

Organic Limestone, coal

Sedimentary rocks

Layers, strata, beds, cross-beds

Sedimentary rocks

Sedimentary rocks

Sedimentary rocks

Igneous Rocks

Crystalline, have all cooled from a liquid Basalt, granite, diabase

Volcanic-- where the magma (lava) cools above

ground basalt

Intrusive-- where the magma cools underground Granite, diabase

Igneous rocks

Igneous rocks

Igneous rocks

Igneous rocks

Metamorphic Rocks

These are also crystalline rocks Rocks that have been changed by heat and/or

pressure Start with one type of rock and end up with another

(Romans 12:1-2) Change occurs without melting anything

An example: metamorphism of a shale Shale slate phyllite schist gneiss melt

Metamorphic rocks

Slate Phyllite

Schist Gneiss

4. Dating of rocks

Relative Dating Superposition Cross-cutting relationships

Absolute (Radiometric) Dating Can only be done with crystalline rocks (igneous &

metamorphic)

Dating of rocks

Dating of rocks

Dating of rocks

HOW DOES RADIOACTIVE DATING WORK?

A rock with orthoclase (KAlSi3O8)

A zircon crystal (ZrSiO4)

A bone with 14C

40K 40K

40K 40K 40K

40K

238U

238U

238U

238U

238U

238U

40K 40K

40K 40Ar 40Ar

40Ar

206Pb

238U

238U

206Pb

206Pb

238U

TIME

½ life of 40K = 1.3 Ga

½ life of 238U = 4.5 Ga

½ life of 14C = 5,730 years

What assumptions must be made?

1. Constant rate of

decay

2. Starting conditions

3. Closed system (no gain/loss of ingredients)

5. Faults

Faults

Graben

Horst

6. Folds

5. Folds

Folds

7. Unconformities

Unconformities

32

The development of

an angular unconformity.

8. volcanoes

9. Mass Wasting

Landslides Avalanches Mud flows Debris flows Slumps

Mass Movements

35

10. Plate Tectonics Fit of continents Fossil patterns across oceans Structural patterns across oceans Rock patterns across oceans Geometry of ocean floor Location of earthquakes, trenches,

mountains, volcanos Volcanic island chain patterns

37

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Motion at Plate Boundaries