1. Education

Your suggestion is on its way!

An email with a link to:

http://geology.about.com/popular.htm

was emailed to:

Thanks for sharing About.com with others!

Most Emailed Articles

Now We Can Begin

Geology: Most Popular Articles

These articles are the most popular over the last month.
Identify Almost Any Rock with This Table
Identify 43 of the most common rock types: igneous, sedimentary and metamorphic.
What Is Chemical Weathering?
A short explanation of chemical weathering.
See the Densities of the Most Common Rock Types
Density, or specific gravity, of common rock types.
Use This Master Index of Rock Pictures
My master alphabetical guide to igneous, sedimentary and metamorphic rock pictures.
What to Know About Sedimentary Rocks
Introducing sedimentary rocks, second of the three great rock classes (along with igneous and metamorphic rocks).
What Is the Most Common Mineral on Earth?
This question has several answers, depending on what a mineral is and what part of the Earth we're talking about.
What to Know About Igneous Rocks
Introducing igneous rocks, first of the three great rock classes (along with sedimentary and metamorphic rocks).
The Most Common Green Minerals in Nature
A guide to the most common and significant green and greenish minerals.
Why the Earth's Crust Is So Important
The Earth's crust is exceptionally important, and not just because we live on it.
What Makes Metamorphic Rocks Special
Most of the thousands of rare minerals known to science occur in metamorphic rocks, which are formed by great heat and pressure. Introducing
6 Things to Know About the Earth's Mantle
A six-part look at the basics of the Earth's mantle, the part between the crust and the core.
Identify Typical Minerals with This Master...
My master guide to annotated pictures to help you identify minerals: typical examples of rock-forming, accessory, and rare or notable minerals.
Viewing Earth from on High
Satellite views of Earth's surface make possible geological discoveries never before imagined.
10 Steps to Help You Identify Any Mineral
Mineral identification starts with picking a good specimen.
What Is My Blue or Purple Mineral?
A guide to the most common and significant blue and purple minerals.
Gneiss
Gneiss is a major metamorphic rock type from regional metamorphism. Page 6.
Schist
Schist is a major metamorphic rock type from regional metamorphism. Page 15.
What a Black Mineral Is Most Likely to Be
A guide to the most common and significant black minerals.
Why Granite is the Signature Rock of Earth
Granite is the signature rock of the continents. Here are the basics of this important stone.
Fault Types in a Nutshell
The three basic types of fault, with their nomenclature, in a nutshell.
Slate
Slate is a major metamorphic rock type from regional metamorphism. Page 17.
Granite
Granite is one of the major igneous rock types. Page 8.
Serpentinite
Serpentinite is a major metamorphic rock type from regional metamorphism. Page 16.
Exfoliation
How big rock domes peel off in shells. Page 6.
Gabbro
Gabbro is one of the major igneous rock types. Page 7.
Index Fossils: The Key to Telling Deep Time
The concept of index fossils is the very basis of geologic dating.
Diorite
Diorite is one of the major igneous rock types. Page 4.
Where to Look for Rocks and Minerals
Rocks and minerals can be found everywhere, but there is a learning process involved.
How to Look at a Rock Like a Geologist
Notes on the most basic operation in geology.
Siltstone
Siltstone is one of the major types of sedimentary rocks. Page 24.
Quartzite
Quartzite is a major metamorphic rock type from regional metamorphism. Page 14.
Scoria
Scoria is one of the major igneous rock types. Page 22.
Pegmatite
Pegmatite is one of the major igneous rock types. Page 14.
Obsidian
Obsidian is one of the major igneous rock types. Page 13.
Rock Gypsum
Rock gypsum is one of the major types of sedimentary rocks. Page 20.
Pumice
Pumice is one of the major igneous rock types. Page 18.
Phyllite
Phyllite is a major metamorphic rock type from regional metamorphism. Page 13.
Basalt
Basalt is one of the major igneous rock types. Page 3.
Igneous Rock Types
The major igneous rock types, plutonic, intrusive and extrusive.
Peridotite
Peridotite is one of the major igneous rock types. Page 15.
Syenite
Syenite is one of the major igneous rock types. Page 23.
Granodiorite
Granodiorite is one of the major igneous rock types. Page 9.
Rhyolite
Rhyolite is one of the major igneous rock types. Page 21.
Tonalite
Tonalite is a felsic plutonic rock without alkali feldspar. Page 24.
More Than 50 Different Landforms in Pictures
Find and see geological landforms at About.com Geology.
How to Tell the Feldspar Minerals Apart
Feldspar is the commonest mineral in the Earth's crust, but identifying it can be tricky.
Metamorphic Rock Types
The major metamorphic rock types, from regional, contact and mechanical metamorphism.
Pyroxenite
Pyroxenite is one of the major igneous rock types. Page 19.
Porphyry
Porphyry is one of the major igneous rock types. Page 17.
Sedimentary Rock Types
The major types of sedimentary rocks.
Marble
Marble is a major metamorphic rock type from regional metamorphism. Page 10.
Fossil Picture Gallery
Pictures of fossils, part of the About.com Geology gallery of images.
Dunite
Dunite is a plutonic rock consisting of olivine. Page 5.
Felsite
Felsite is one of the major igneous rock types. Page 6.
Quartz: How to Tell It, Different Kinds, What...
Quartz is essential to the land as we know it.
The Size Divisions of Sediment Particles
The grain sizes of sediments and sedimentary rocks are a matter of great interest to geologists. Here is a guide to sediment grades and grain sizes.
What Is My Red or Pink Mineral?
A guide to the most common and significant red and pink minerals.
Mechanical Weathering
A short explanation of mechanical weathering.
Shale
Shale is one of the major types of sedimentary rocks. Page 23.
Perlite
Perlite is one of the major igneous rock types. Page 16.
Texas Geologic Map
Geologic map of Texas, part of a set of all 50 states. Page 43.
Quartz Monzonite
Quartz monzonite is one of the major igneous rock types. Page 20.
Greenstone
Grenstone is a major metamorphic rock type from regional metamorphism. Page 8.
How to Use the Mohs Hardness Scale to Identify...
The 10-mineral Mohs scale of relative hardness is based on what scratches what.
Komatiite
Komatiite is a rare and ancient ultramafic lava. Page 11.
Kimberlite
Kimberlite is the peculiar deep-seated ultramafic rock most famous as the ore of diamonds. Page 10.
Andesite
Andesite is one of the major igneous rock types.
Sandstone: What It Is and What It Tells Us
Sandstone is sand cemented together into rock.
Troctolite
Troctolite is one of the gabbroid rocks: igneous, plutonic and mafic. Page 25.
Fast Links for Real-Time Info on Current...
Directions to information and data from earthquakes as fast as possible.
Where Are the Greatest Earthquake Threats in...
The United Nations' global map of seismic hazard
Latite
Latite is the extrusive equivalent of monzonite. Page 12.
Geologic Maps of the 50 United States
Geologic maps of all 50 U.S. states.
Colorado Geologic Map
Geologic map of Colorado, part of a set of all 50 states. Page 6.
Migmatite
Migmatite is a major metamorphic rock type from regional metamorphism. Page 11.
Translate Names Between Gemstones and Minerals
Big list of mineral names and their corresponding gemstone names.
Limestone
Limestone is one of the major types of sedimentary rocks. Page 17.
Anorthosite
Anorthosite is one of the major igneous rock types. Page 2.
Greenschist
Greenschist is a major metamorphic rock type from regional metamorphism. Page 7.
Geologic Gift Ideas
A few suggestions for something to get your favorite geologist.
Chert
Chert is one of the major types of sedimentary rocks. Page 7.
Sandstone
Sandstone is one of the major types of sedimentary rocks. Page 22.
California Geologic Map
Geologic map of California, part of a set of all 50 states. Page 5.
Tuff
Tuff is one of the major igneous rock types. Page 26.
Plutonic Rocks
Plutonic rocks defined and explained.
Arkose
Arkose is one of the major types of sedimentary rocks. Page 2.
Travertine
Travertine is one of the major types of sedimentary rocks. Page 25.
Mylonite
Mylonite is a major metamorphic rock type from mechanical metamorphism. Page 12.
Soapstone
Soapstone is a major metamorphic rock type from regional metamorphism. Page 18.
Minerals with Metallic Luster
Minerals with metallic luster are easy to learn to identify.
The Lithosphere in a Nutshell
What you need to know about the lithosphere.
Hornfels
Hornfels is a major metamorphic rock type from contact metamorphism. Page 9.
The Scientific Definition of a Mineral
Minerals meet four criteria, more or less strict.
Rock Salt
Rock salt is one of the major types of sedimentary rocks. Page 21.
Graywacke or Wacke
Wacke or graywacke is one of the major types of sedimentary rocks. Page 15.
Rock Cycle Diagram
The rock cycle as I see it. Geology.
North Carolina Geologic Map
Geologic map of North Carolina, part of a set of all 50 states. Page 33.
Mineral Pictures A to Z
A-to-Z list of minerals shown on About.com Geology.
What to Know Before You Buy a Magnifier
What to think about and look for when you set out to get a nice magnifier.
Coquina
Coquina is one of the major types of sedimentary rocks. Page 11.
About Convergent Zones in Plate Tectonics
Basics of plate tectonics: convergent zones are where plates come together.
Plate Tectonics Explains How the Earth's...
Start here to learn the basics of plate tectonics.
Conglomerate
Conglomerate is one of the major types of sedimentary rocks. Page 10.
Top-Level Geologic Time Scale: Eons, Eras and...
The periods of geologic time, part of the official geologic time scale.
Alabaster
Alabaster or massive gypsum rock is one of the sedimentary rocks.
Georgia Geologic Map
Geologic map of Georgia, part of a set of all 50 states. Page 10.
Ironstone
Several types of sedimentary rocks are called ironstone. Page 16.
Earthquakes - The Basics in a Nutshell
Start here for the seismic basics: faults that cause earthquakes, types of seismic waves, damages they cause and more.
Frost Heave
Freezing ground ice lifts and shifts sediment. Page 7.
Claystone
Claystone is a type of sedimentary rock. Page 8.
Quartz
Quartz is classified as a rock-forming mineral. Page 9.
About Subduction in Plate Tectonics
Basics of plate tectonics: introduction to subduction.
Sizes of Tectonic or Lithospheric Plates
Table listing the lithosphere's tectonic plates by oder of size.
Michigan Geologic Map
Geologic map of Michigan, part of a set of all 50 states. Page 22.
Utah Geologic Map
Geologic map of Utah, part of a set of all 50 states. Page 44.
Dolomite Rock or Dolostone
Dolomite or dolostone is one of the major types of sedimentary rocks. Page 14.
Burning Coal as a Home Fuel
Americans don't burn coal at home any more, but it still works for much of the world.
About Transforms - Plate Tectonic Transform...
Basics of plate tectonics: what happens when plates move past each other.
Peat
Peat is one of the major types of sedimentary rocks. Page 18.
Blueschist
Blueschist is a major metamorphic rock type from regional metamorphism. Page 3.
What Is My Yellow Mineral?
A guide to the most common and significant yellow minerals.
Breccia
Breccia is one of the major types of sedimentary rocks. Page 6.
Measuring Plate Motion
The five ways we track the motion of the lithospheric plates.
South Carolina Geologic Map
Geologic map of South Carolina, part of a set of all 50 states. Page 40.
What Counts as a Rock to a Geologist?
Everyone knows what a rock is, until you ask what it is exactly.
Actinolite
Actinolite is a major amphibole mineral. Page 5.
Minnesota Geologic Map
Geologic map of Minnesota, part of a set of all 50 states. Page 23.
Eclogite
Eclogite is a major metamorphic rock type from regional metamorphism. Page 5.
Argillite
A lightly metamorphosed claystone also called pipestone. Page 2.
Banded Iron Formation
Banded iron formation or BIF is one of the major types of sedimentary rocks. Page 4.
Steno Started Geology with a Few Simple...
Steno (Niels Stensen) first set forth some of the basic principles that all geologists follow.
Coal
Coal is one of the major types of sedimentary rocks. Page 9.
Florida Geologic Map
Geologic map of Florida, part of a set of all 50 states. Page 9.
Volcanic (Extrusive) Rock Types
Photos of the types of erupted igneous rocks.
Diatomite
Picture and notes about the sedimentary rock diatomite. Page 13.
What You Should Know About the San Andreas Fault
Home page for everything about the San Andreas fault: where it is, how it behaves, what it means.
Natural Asphalt
Natural asphalt is one of the major types of sedimentary rocks. Page 3.
North Dakota Geologic Map
Geologic map of North Dakota, part of a set of all 50 states. Page 34.
Porcellanite
Porcellanite is a subtle sedimentary rock type. Page 19.
South Dakota Geologic Map
Geologic map of South Dakota, part of a set of all 50 states. Page 41.
The Official State Gemstones, In One List
Thirty-five states have official gemstones. Here they are, listed by state.
Talus or Scree
Talus is loose rock lying on a mountain slope. Page 12.
Erosion: Introduction to This Central Concept...
A short explanation of erosion. Geology.
Age of the Ocean Floor
Seafloor age map for the woarld.: national geophysical data geophysical data center plate tectonic maps digital isochrons national geophysical data center
Uranium-Lead Dating
Uranium-lead method is the oldest and, when done carefully, the most reliable isotopic dating method.
Amethyst
Amethyst specimen showing typical shapes of quartz crystals. Page 8.
Missouri Geologic Map
Geologic map of Missouri, part of a set of all 50 states. Page 25.
Olivine
Olivine is an important rock-forming mineral. Page 7.
Pluton
Plutons defined and explained. Plutons are bodies of plutonic rock: deep-seated and large-grained.
Feldspar (Orthoclase)
Feldspar is a major rock-forming mineral. Page 5.

©2014 About.com. All rights reserved.