ROCKS AND EARTH HISTORY

THE FOURTH DIMENSION

INSTRUCTIONS

GENERAL INTRODUCTION

PART I: ROCKS AND ROCK-FORMING PROCESSES

WHAT IS A ROCK?

HOW DO ROCKS FORM?

Attachment by Intergrowth

Attachment by Cementation

~ ENVIRONMENTS OF ROCK FORMATION ~
	Introduction
IGNEOUS
	In a Magma Chamber
	In a Lava Flow
SEDIMENTARY
	In a Deposit of Sediment: ~ Origin by Grain Overgrowth
	In a Deposit of Sediment: ~ Origin by Cementation
	In a Salt Water Lake
	In a Hypersaline Part of the Ocean
METAMORPHIC
	Under Heat and Pressure

HOW CAN THE WAY IN WHICH A ROCK FORMED BE DETERMINED?

~ FOUR CLUES TO ROCK ORIGIN ~

1. Rock Mineralogy

2. Rock Texture

3. Rock Structure

	Primary Structures: Layering - 1
	Primary Structures: Layering - 2
	Other Primary Structures
	Secondary Structures

4. Field Relationships

	The Secondary Character of Slaty Cleavage
	The Origin of Slaty Cleavage
	The Origin of Cross-Cutting Rock Bodies
	Igneous Origin: Observed and Inferred
	Metamorphic Origin: Observed and Inferred
	Sedimentary Origin: Observed and Inferred

Conclusions

PART II: ROCKS AND EARTH HISTORY

INTRODUCTION

	Time: Introduction
	Relative Age
	Absolute Age
	Unfolding the History of the Earth
	Questions and Conclusions