Geology Sitemap - Page 1 2016-09-26

Apatite - Phosphate Minerals
Apatite is the principal phosphate mineral.

Pyromorphite - Phosphate Minerals
Pyromorphite is a significant phosphate mineral and ore of lead. Page 3.

Turquoise - Phosphate Minerals
Turquoise, a precious gemstone, is also a phosphate mineral. Page 4.

Variscite - Phosphate Minerals
Variscite is a colorful phosphate mineral common in rock shops. Page 5.

Sulfate Minerals - Alunite Picture
Alunite is one of the sulfate minerals.

Sulfate Minerals - Anglesite Picture
Anglesite is one of the sulfate minerals. Page 2.

Sulfate Minerals - Anhydrite Picture
Anhydrite is one of the sulfate minerals. Page 3.

Sulfate Minerals - Barite Picture
Barite is one of the sulfate minerals. Page 4.

Sulfate Minerals - Celestine or Celestite Picture
Celestine or celestite is one of the sulfate minerals. Page 5.

Sulfate Minerals - Gypsum Rose Picture
Gypsum is one of the sulfate minerals. Page 6.

Sulfate Minerals - Selenite Gypsum Picture
Gypsum, in its clear crystalline form selenite, is one of the sulfate minerals. Page 7.

Bornite - Sulfide Minerals
Bornite is one of the sulfide minerals.

Chalcopyrite - Sulfide Minerals
Chalcopyrite is one of the sulfide minerals. Page 2.

Cinnabar - Sulfide Minerals
Cinnabar is one of the sulfide minerals. Page 3.

Galena - Sulfide Minerals
Galena is one of the sulfide minerals. Page 4.

Marcasite - Sulfide Minerals
Marcasite is one of the sulfide minerals. Page 5.

Molybdenite - Sulfide Minerals
Molybdenite is one of the sulfide minerals. Page 7.

Pyrite - Sulfide Minerals
Pyrite is one of the sulfide minerals. Page 8.

Sphalerite - Sulfide Minerals
Sphalerite is one of the sulfide minerals. Page 9.

Analcime (Analcite) - The Zeolite Minerals
Analcime is one of the common zeolite minerals.

Chabazite - The Zeolite Minerals
Chabazite is one of the common zeolite minerals. Page 2.

Heulandite - The Zeolite Minerals
Heulandite is one of the common zeolite minerals. Page 3.

Laumontite - The Zeolite Minerals
Laumontite is one of the common zeolite minerals. Page 4.

Natrolite - The Zeolite Minerals
Natrolite is one of the common zeolite minerals. Page 5.

Stilbite - The Zeolite Minerals
Stilbite is one of the common zeolite minerals. Page 6.

Metacinnabar - Sulfide Minerals
Metacinnabar is one of the sulfide minerals. Page 6.

Lazulite - Phosphate Minerals
Lazulite is an uncommon phosphate mineral. Page 2.

Bronzite - The Pyroxene Minerals
Bronzite is a field term for intermediate pyroxenes in the enstatite-ferrosilite series. Page 4.

Mg-Fe-Ca Pyroxene Ternary Diagram - Classifying the Pyroxene Minerals
Enstatite-ferrosilite-wollastonite ternary diagram of the Mg-Fe-Ca pyroxene minerals. Page 13.

Aegirine - Pyroxene Minerals
Aegirine is one of the pyroxene minerals.

Babingtonite - Pyroxene Minerals
Babingtonite is one of the pyroxene minerals. Page 3.

Diopside - Pyroxene Minerals
Diopside is one of the pyroxene minerals. Page 5.

Enstatite - Pyroxene Minerals
Enstatite is one of the pyroxene minerals. Page 6.

Jadeite - Pyroxene Minerals
Jadeite is one of the pyroxene minerals. Page 7.

Neptunite - Pyroxene Minerals
Neptunite is one of the pyroxene minerals. Page 8.

Omphacite - Pyroxene Minerals
Omphacite is one of the pyroxene minerals. Page 9.

Augite - Pyroxene Minerals
Augite is one of the pyroxene minerals. Page 2.

Rhodonite - Pyroxene Minerals
Rhodonite is one of the pyroxenoid minerals. Page 10.

Spodumene - Pyroxene Minerals
Spodumene is one of the pyroxene minerals. Page 11.

Wollastonite - Pyroxene Minerals
Wollastonite is one of the pyroxene minerals. Page 12.

Sodium Pyroxene Ternary Diagram
Ternary diagram for the sodium pyroxene mineral species. Page 14.

Mineral Identification Guides
Selected identification guides for minerals.

Minerals and Mineralogy
Minerals, their identification, and the deeper science behind them.

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Minerals with Metallic Luster
Minerals with metallic luster are easy to learn to identify.

All About Salt - The Most Intimate Mineral
Salt is the only dietary mineral that's really a mineral. It comes from the sea and from solid layers underground.

Weathering Defined and Explained
The definition of weathering is the gradual destruction of rock under surface conditions. Think of the Grand Canyon or other rock formations.

Abrasive Minerals
Natural mineral abrasives are often still used today. This survey of several mineral substances explains the properties that make them useful abrasives.

About Rocks and Rock Collecting
Rocks of all types: how to identify them, how they form, what they mean.

Guide to Common Green and Greenish Minerals
A guide to the most common and significant green and greenish minerals. Includes images and descriptions​ of each type.

An Index Page of Rock Types and Pictures
A master alphabetical guide to igneous, sedimentary and metamorphic rocks. Includes pictures of each type as well as a brief description.

Where to Look for Rocks and Minerals
Learn the basics of rocks and minerals, where to find them and what they mean in their context.

Feldspar Distinctions, Characteristics & Identification
An overview of the most common mineral in the Earth's crust, feldspar- how to identify it and further information.

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Black Minerals - The Most Common and Significant
A guide to the most common and significant black minerals.

Common Blue, Purple and Violet Minerals Guide
Blue, violet and purple colors can be seen in many different minerals. Here is a look at some of the most common.

Igneous Rocks: Everything You Need to Know
All igneous rocks have one thing in common: they occur from the cooling and solidification of molten material.

Landforms and Geologic Features
About landforms, geologic features and the geologic structures that form them.

Geologic Processes and Features
Agents of geologic change and the geologic signs they leave on the rocks and land.

Lakes
The geological side of lakes: limnology and limnogeology.

Plate Tectonics
Introductory and general sources about this important theory of the Earth.

The Earth's Crust: Everything You Need to Know
The Earth's crust is the thin, rocky layer that makes up our planet's shell. It is exceptionally important, and not just because we live on it.

Most Famous and Influential Geologists
These influential and important geologists forever changed the way that humans think about the planet.

Transform Boundaries, Defined and Explained
Transform boundaries or transform faults occur wherever the Earth's plates move past each other.

Measuring Earthquake Magnitudes
Decades of scientific work have gone into developing ways to qualitatively measure earthquake magnitude.

Geology Apps for iPhones, iPads and Androids
From geologic mapping to earthquake reporting, here is a list of useful geoscience apps for iPhone, iPad and Android.

Mineral Lusters - Glassy or Vitreous Luster - Aragonite
An example of aragonite with glassy luster. Page 25.

Glassy or Vitreous Luster in Actinolite
An example of actinolite with glassy or vitreous luster. Page 16.

Mineral Lusters - Glassy or Vitreous Luster - Calcite
An example of calcite with glassy luster. Page 26.

Metallic Luster in Chalcopyrite
An example of chalcopyrite with metallic luster. Page 4.

Metallic Luster in Galena
An example of galena with metallic luster.

Metallic Luster in Gold
An example of gold with metallic luster. Page 2.

Submetallic Luster in Hematite
An example of hematite with submetallic luster. Page 6.

Metallic Luster in Magnetite
An example of magnetite with metallic luster. Page 3.

Metallic Luster in Pyrite
An example of pyrite with metallic or submetallic luster. Page 5.

Waxy Luster in Chalcedony
An example of chalcedony, or cryptocrystalline quartz, with waxy luster in chert. Page 19.

Glassy or Vitreous Luster in Quartz
An example of quartz with glassy or vitreous luster. Page 12.

Resinous Luster in Spessartine Garnet
An example of spessartine garnet with resinous luster. Page 18.

Pearly Luster in Talc
An example of talc with pearly luster. Page 21.

Glassy or Vitreous Luster in Topaz
An example of topaz with glassy or vitreous luster. Page 14.

Mineral Lusters - Glassy or Vitreous Luster - Tourmaline
An example of tourmaline, specifically black schorl, with nontraditional glassy luster. Page 27.

Waxy Luster in Variscite
An example of variscite with waxy luster. Page 20.

Adamantine Luster in Zircon
An example of zircon with adamantine luster. Page 9.

Resinous Luster in Amber
An example of amber with resinous luster. Page 17.

Dull or Earthy Luster in Chrysocolla
An example of chrysocolla with a dull or earthy luster. Page 24.

Adamantine Luster in Cinnabar
An example of cinnabar with adamantine luster. Page 11.

Adamantine Luster in Andradite Garnet
An example of andradite, sometimes called demantoid garnet, with adamantine luster. Page 10.

Adamantine Luster in Diamond
An example of diamond with adamantine luster. Page 7.

Mineral Luster: Examples and Information
Examples of the different types of luster, or the way light interacts with the surface of a mineral.

Mineral Luster: Examples and Information
Examples of the different types of luster, or the way light interacts with the surface of a mineral.

Mineral Luster: Examples and Information
Examples of the different types of luster, or the way light interacts with the surface of a mineral.

Pearly Luster in Muscovite
An example of muscovite with pearly luster. Page 22.

Glassy or Vitreous Luster in Olivine
An example of olivine with glassy or vitreous luster. Page 13.

Dull or Earthy Luster in Psilomelane
An example of psilomelane with dull or earthy luster. Page 23.

Adamantine Luster in Ruby
An example of ruby with adamantine luster. Other conundrums can display adamantine luster as well. Page 8.

Glassy or Vitreous Luster in Selenite
An example of selenite which displays glassy or vitreous luster that borders on resinous. Page 15.

Disposing Nuclear Waste in Ocean Trenches
Disposing of nuclear waste in subduction zones, or oceanic trenches, may seem like a good idea, but it simply isn't plausible.

Geology and Topography of Antarctica
Although Antartica is almost entirely covered by glaciers, geologists are slowly beginning to understand what lies below the ice.

Geology of the Appalachian Mountains
The Appalachian Mountains contain a very complex (and lengthy) geologic history. Learn more about what makes them so special.

Coal in a Nutshell
Coal, a fossil fuel, is formed when plant matter becomes buried and compacted in an anoxic environment.

Earthquake Resources for the Western United States
Quake-related information--maps, reports, advice--for the United States west of the Rockies.

Deep Time and Geologic History
Deep time refers to the entirety of geologic history, an unimaginable length of time that goes far beyond our human scale.

Prepare for Earthquakes
Resources for helping you do whatever it takes to safeguard your lives and homes, before the next big one strikes.

10 Steps to Take for Earthquake Preparedness
Developed by earthquake professionals, these 10 steps of action are important elements of a disaster-resilient society.

May 18, 1980: the Deadly Eruption of Mount St. Helens
Remembering David Johnston, a young volcanologist who was killed during the May 18, 1980 eruption of Mount St Helens.

Geology on About.com - The Complete Guide to Geoscience
Facts and photos on everything from the Earth's core to outer space, from the oldest fossils to the landslides and earthquakes of today.

Coso Geothermal Field, California - Geologic Map of the Coso Range
Geologic map of the Coso Range, site of the Coso geothermal field. Page 3.

Coso Geothermal Field, California - Obsidian Tools
The Coso geothermal field was valued by Indians as an obsidian source. Page 5.

Official State Rocks and State Stones of the United States - Bauxite - State Rock of Arkansas
Bauxite, or aluminum ore, is the state rock of Arkansas.

Official State Minerals of the United States - Talc - State Mineral of Vermont
Talc is the state mineral of Vermont

Official State Minerals of the United States - Staurolite - State Mineral of Georgia
Staurolite is the state mineral of Georgia

Sutter Buttes, California - Rampart Pyroclastic Deposits
Pyroclastic deposits in the Rampart of the Sutter Buttes.

Sutter Buttes, California - North Butte in the Sutter Buttes
North Butte in the Sutter Buttes, in California's Sacramento Valley.

Northern San Andreas Fault - Index Map
Index map of the northern San Andreas fault.

Northern San Andreas Fault - Eureka Canyon, Santa Cruz Mountains
Looking across the northern San Andreas fault to distant Ben Lomond in the Santa Cruz Mountains.

Obsidian Picture Gallery - Spherulites in Obsidian
Obsidian may contain 'bubbles' of mineral matter called spherulites.

1857 Earthquake Segment San Andreas Fault - Tejon Pass Gouge
Fault gouge on the trace of the San Andreas fault near Gorman.

Salton Sea Seep Field - Twin Peaks in a Gryphon
Detail of a mud volcano vent in the Davis-Schrimpf seep field.

Mud Volcano, California - Depositional Landform Pictures
Mud volcanoes of all sizes are depositional landforms.

Wave-Cut Platforms - Tectonic Platform, Santa Monica, California
Wave-cut platform in Santa Monica, California

1857 Earthquake Segment San Andreas Fault - Neenach Volcanics Obsidian
Neenach Volcanics obsidian from Pine Canyon Road on the San Andreas fault.

Pyroxene Minerals - Classification Diagrams for the Pyroxenes
Diagrams to help classify the pyroxene minerals.

Olivine Picture - The Silicate Minerals
Olivine is one of the silicate minerals.

San Andreas Fault at Parkfield - Cholame Valley
. Geology.

Conglomerate of Distal Origin - Conglomerate Picture Gallery
A conglomerate whose stones have come far.

Montana Concretions - Picture Gallery of Concretions
Concretions from Montana, mostly ferruginous.

Basalt Picture Gallery - Fresh and Weathered Massive Basalt
Basalt is black when fresh, brown when weathered.

Volcanic Rock Types - Fresh Obsidian
Fresh obsidian from near the Salton Sea, in the gallery of erupted igneous rocks.

1857 Earthquake Segment San Andreas Fault - Neenach Volcanics Scoria
Neenach Volcanics scoria from Pine Canyon Road on the San Andreas fault.

Extrusive Igneous Rocks - Hawaiian Basalt
Photo of Hawaiian basalt. Geology.

Volcanic Rocks - Obsidian with Weathering Rind
Obsidian cobble with weathering rind, in the gallery of erupted igneous rocks.

Minerals and Gemstones
Minerals, gemstones, and how to identify them.

Rocks of Red Rocks, Colorado - Fountain Formation Arkosic Conglomerate
Closeup of the Fountain Formation of the Colorado Front Range exposed at Red Rocks Park. Page 5.

Rocks of Red Rocks, Colorado - Precambrian Gneiss
Ancient gneiss underlies the Fountain Formation at Red Rocks Park. Page 6.

Rocks of Red Rocks, Colorado - Front Range Hogbacks
Hogbacks of Colorado's Front Range are seen from Red Rocks Park.

Rocks of Red Rocks, Colorado - Ship Rock
Ship Rock from the parking lot at Red Rocks Park. Page 2.

Rocks of Red Rocks, Colorado - Fountain Formation North of Red Rocks
The Fountain Formation of the Colorado Front Range exposed north of Red Rocks Park. Page 3.

Rocks of Red Rocks, Colorado - Red Rocks Unconformity
Unconformity between the Fountain Formation and underlying Precambrian rocks at Red Rocks Park. Page 4.

Geology of Red Rocks, Colorado
Pictures of and information about the distinctive Fountain Formation of the Colorado Front Range exposed at Red Rocks Park.

Sandstone: Everything You Need to Know
Sandstone is made up of three ingredients, sand particles, matrix and cement, and can reveal a great deal of information to geologists.

Tsunamis from Landslides - The Other Kind of Tsunami
Tsunamis can arise from landsliding, with or without an earthquake.

Cross-Peen Crack Hammer - Rock Hammers
Cross-peen crack hammers are very useful in hard-rock country. Page 3.

Geologist's or Prospector's Hammer - Rock Hammers
The prospector's hammer is the most typical rock hammer used by geologists.

Chisel, Mason's or Bricklayer's Hammer - Rock Hammers
The chisel or bricklayer's hammer is used in fossil hunting or examining stratified rocks. Page 2.

Chisel-Tip Rock Pick - Rock Hammers
This chisel-tip rock pick is an antique hammer of uncommon style. Page 4.

Rock Hammers: How to Pick the Correct One
Rock hammers of various sizes and shapes have different functions in the field. Take a look at four different types here.

Do People Still Use Coal as a Home Fuel Source?
Although Americans don't burn coal in the house much anymore, the fossil fuel is used as an energy source for much of the world.

Lithification Defined and Explained
Lithification refers to the process in which sediments are turned into rigid rock through compaction and cementation.

Plutonic Rocks - Definition and Examples
Plutonic rocks form from igneous intrusions deep in the Earth's crust. Common plutonic rocks include granite, tonalite and quartz diorite.

Carbonate Compensation Depth (CCD)
Calcium Carbonate Depth (CCD) explains why limestone formation is normally associated with shallow seas.

About Mercury: The Geology of Quicksilver
The heavy metal element mercury, once known as quicksilver, is of much interest to scientists due to its unique properties and inherent toxicity.

Clayton Lake Dinosaur Tracks - New Mexico Geological Attractions and Destinations
Clayton Lake's dinosaur tracks are one of New Mexico's geological attractions. Page 6.

Cimarron Canyon - New Mexico Geological Attractions and Destinations
Cimarron Canyon is one of New Mexico's geological attractions. Page 5.

Carlsbad Caverns - New Mexico Geological Attractions and Destinations
Carlsbad Caverns is of New Mexico's geological attractions. Page 4.

Bottomless Lakes - New Mexico Geological Attractions and Destinations
Bottomless Lakes are one of New Mexico's geological attractions. Page 2.

Blue Hole - New Mexico Geological Attractions and Destinations
Blue Hole is one of New Mexico's geological attractions.

Dog Canyon - New Mexico Geological Attractions and Destinations
Dog Canyon is one of New Mexico's geological attractions. Page 7.

Kasha-Katuwe Tent Rocks - New Mexico Geological Attractions and Destinations
Kasha-Katuwe Tent Rocks are one of New Mexico's geological attractions. Page 8.

Rockhound State Park - New Mexico Geological Attractions and Destinations
Rockhound State Park is one of New Mexico's geological attractions. Page 9.

Shiprock - New Mexico Geological Attractions and Destinations
Shiprock is of New Mexico's geological attractions. Page 10.

Valles Caldera - New Mexico Geological Attractions and Destinations
Valles Caldera is one of New Mexico's geological attractions. Page 11.

White Sands - New Mexico Geological Attractions and Destinations
White Sands is one of New Mexico's geological attractions. Page 12.

New Mexico Geological Attractions and Destinations
A selection of New Mexico's geological attractions.

Drilling into Faults
Geologists are getting near the places where earthquakes actually happen.

Official List of State Gems
Thirty-five states have official gems or gemstones, while Montana and Nevada have two. Here they all are, along with the date that they were adopted.

Satellite Geology - Viewing Earth from on High
Satellite views of Earth's surface make possible geological discoveries never before imagined.

Stone Tools Then and Now
Stone tools are older than the human species, but still current among today's flint knappers.

Geological Thinking - Method of Multiple Working Hypotheses
The scientific method we're taught in school is a cartoon.

Las Vegas Geology Highlights
Great rock shows are a sure thing around Las Vegas, Nevada.

The Nevada Silver Rush
Oh for the days when horn silver lay on the ground in the Nevada silver rush.

Uranium in a Nutshell
The basics of uranium geology.

Landslides in a Nutshell
Landslides make landscapes the way sculptors work: by removal.

The Promise and Pitfalls of Float (Loose Rock)
Float - loose rocks in the soil - can yield useful geologic information in areas where the bedrock is hidden.

Ancient Remains - Fossil DNA and Other Actual Remains of Former Life
The actual bodies of dead (and living) things can last nearly forever.

Rhenium-Osmium Studies
These two exceedingly rare metals can now be studied for their unique clues to deep Earth history.

Aftershocks Are Not Afterthoughts
Aftershocks can be nasty surprises, even worse than the main event.

A Day of Total Terroir: Geology in the Wine Country
The story of a geologist's day trip around the Napa Valley in search of the elusive quality called terroir.

Tsunamis Caused by Weather - Meteotsunamis
In certain places the weather, not earthquakes, can cause tsunamis.

Connecticut Geology - A Long and Eventful Geologic History
Born-and-bred Westerners may find that Connecticut's laid-back landscape is way cool.

Is It Bad Luck to Take Rocks?
If you think it might be wrong to take away a rock from somewhere, listen to that voice in your head because you're probably right.

What Is Shungite?
The 'magic mineral' shungite is interesting but not as special as all that.

Public Parks that Allow Fossil Collecting
Public parks in the United States where you can collect fossils legally.

Public Parks that Allow Fossil Collecting
Public parks in the United States where you can collect fossils legally.

A Day on the Hayward Fault
Take a close look at the treacherous Hayward fault of California.

Pinto Mountains Bajada, Joshua Tree National Park
Bajada at the foot of the Pinto Mountains in Joshua Tree National Park.

Pinto Basin, Joshua Tree National Park
The edge of the Basin and Range province in Joshua Tree National Park.

Boulder Pile in the Pinto Basin, Joshua Tree National Park
A gneiss inselberg in Joshua Tree National Park.

Lost Horse Valley in Joshua Tree National Park
Central place in Joshua Tree National Park.

Formation of Boulders in Joshua Tree National Park
How those huge round boulders form in Joshua Tree National Park.

Boulder Sea in Joshua Tree National Park
A wide area covered with large boulders in Joshua Tree National Park.

Pinto Gneiss in Joshua Tree National Park
The gneiss of the eastern part of Joshua Tree National Park.

Dry Wash in Joshua Tree National Park
A seasonal tree-studded watercourse in Joshua Tree National Park.

Pinto Basin and the Playa, Joshua Tree National Park
A dry lake bed or playa in eastern Joshua Tree National Park.

Granite of Joshua Tree National Park
Granite forms the western part of Joshua Tree National Park.

Rampart of Hidden Valley, Joshua Tree National Park
High rocky walls of Hidden Valley in Joshua Tree National Park.

Adams' Tor, Joshua Tree National Park
Ansel Admas photographed this tor in Joshua Tree National Park.

Desert Pavement in Joshua Tree National Park
Example of desert pavement in Joshua Tree National Park.

A Tour of Joshua Tree National Park
A photo tour of the geologic highlights of Joshua Tree National Park, in California's desert lands.

Boulder Pile in Joshua Tree National Park
Inselbergs and boulder piles dot Joshua Tree National Park.

Desert Pavement Theories
A lot of geologic history may hide under the rug of the desert pavement.

The Earth's Core - Its Structure and Possible Composition
The whole Earth on average consists of the same mixture of stuff we see elsewhere in the solar system, but the core has to be iron metal along with some nickel.

Sprites: Upper Atmospheric Lightning
These ghostly flickerings in the ionosphere are the coolest things in the sky.

How Sprites Are Studied
Studying sprites takes fast cameras, luck and friends in high places. Page 2.

Geology and Production of Iron
Earth's earliest conditions led to the formation of gigantic beds of iron ore.

Amygdules
Amygdules are vesicles filled with minerals.

Earthflow
An earthflow on a California hillside.

Plutons, Defined and Explained
Plutons are deep-seated bodies of large-grained igneous rock. They can be exposed at the surface if erosion wears away overlying rock.

What Is Geology's Nobel Prize?
Nothing in geology quite measures up to the Nobel Prize.

The Snowball Earth
The

Travel for Geologists
Places to travel for geologists, or those who enjoy geology and geologic destinations.

Zircon, Zirconia, Zirconium Minerals
The zirconium minerals zircon, baddeleyite and zirconolite are a close family.

How to Travel Like a Geologist
With geo-safaris you bring back not trophies but knowledge to use at home.

California Transect - Key Map of Geology
A photographic field trip to classic subduction-related rocks across northern California. Page 2.

California Transect - The Subduction Setting
A photographic field trip to classic subduction-related rocks across northern California.

California Transect - Map of Stops, Days 2 and 3
A photographic field trip to classic subduction-related rocks across northern California. Page 4.

California Transect - Map of Stops, Days 1 and 4
A photographic field trip to classic subduction-related rocks across northern California. Page 3.

California Transect
A photographic field trip to classic subduction-related rocks across northern California.

California Transect
A photographic field trip to classic subduction-related rocks across northern California.

California Transect
A photographic field trip to classic subduction-related rocks across northern California.

California Transect
A photographic field trip to classic subduction-related rocks across northern California.

California Transect
A photographic field trip to classic subduction-related rocks across northern California.

California Transect
A photographic field trip to classic subduction-related rocks across northern California.

California Transect
A photographic field trip to classic subduction-related rocks across northern California.

California Transect
A photographic field trip to classic subduction-related rocks across northern California.

California Transect
A photographic field trip to classic subduction-related rocks across northern California.

California Transect
A photographic field trip to classic subduction-related rocks across northern California.

New York Geologic Map
Geologic map of New York, part of a set of all 50 states. Page 32.

Wyoming Geologic Map
Geologic map of Wyoming, part of a set of all 50 states. Page 50.

Kettles, Alaska - Glacier Picture Gallery
Kettles dot the outwash plain of Bering Glacier in Alaska. Page 16.

Lateral Moraine, Alaska - Glacier Picture Gallery
Lateral moraine in Glacier Bay, Alaska. Page 17.

Medial Moraines, Alaska - Glacier Picture Gallery
Medial moraines stripe Johns Hopkins Glacier, Alaska. Page 18.

Outwash Plain, Alberta - Glacier Picture Gallery
Peyto Glacier ends in an outwash plain. Page 19.

Piedmont Glacier, Alaska - Glacier Picture Gallery
Taku Glacier's piedmont segment spreads out on flat ground. Page 20.

Roche Moutonnee, Wales - Glacier Picture Gallery
Welsh glaciers sculpted this roche moutonnee. Page 21.

Rock Glacier, Alaska - Glacier Picture Gallery
Rock glacier in Alaska's Chugach Mountains. Page 22.

Seracs, New Zealand - Glacier Picture Gallery
Seracs stand on a New Zealand glacier. Page 23.

Terminal or End Moraine, Alaska - Glacier Picture Gallery
Nellie Juan Glacier leaves behind a terminal or end moraine. Page 25.

Valley or Mountain or Alpine Glacier, Alaska - Glacier Picture Gallery
Bucher Glacier, a typical valley - or mountain or alpine - glacier. Page 26.

Watermelon Snow - Glacier Picture Gallery
This rosy tint is made by a snow-loving microbe. Page 27.

Rhode Island Geologic Map
Geologic map of Rhode Island, part of a set of all 50 states. Page 39.

South Carolina Geologic Map
Geologic map of South Carolina, part of a set of all 50 states. Page 40.

South Dakota Geologic Map
Geologic map of South Dakota, part of a set of all 50 states. Page 41.

Tennessee Geologic Map
Geologic map of Tennessee, part of a set of all 50 states. Page 42.

Texas Geologic Map
Geologic map of Texas, part of a set of all 50 states. Page 43.

Utah Geologic Map
Geologic map of Utah, part of a set of all 50 states. Page 44.

Virginia Geologic Map
Geologic map of Virginia, part of a set of all 50 states. Page 46.

Vermont Geologic Map
Geologic map of Vermont, part of a set of all 50 states. Page 45.

Washington Geologic Map
Geologic map of Washington, part of a set of all 50 states. Page 47.

Wisconsin Geologic Map
Geologic map of Wisconsin, part of a set of all 50 states. Page 49.

West Virginia Geologic Map
Geologic map of West Virginia, part of a set of all 50 states. Page 48.

Arete - Glacier Picture Gallery
A jagged arete in Alaska glacier country.

Bergschrund - Glacier Picture Gallery
Bergschrund in the Swiss Alps. Geology. Page 2.

Cirque or Corrie Glacier - Glacier Picture Gallery
A glacier that sits in a cirque. Page 4.

Drumlin, Ireland - Glacier Picture Gallery
Streamlined hillocks of glacial sediment. Page 5.

Erratic, New York - Glacier Picture Gallery
A glacial erratic boulder in New York City's Central Park. Page 6.

Esker, Manitoba - Glacier Picture Gallery
An esker, cut by a road, winds across Manitoba. Page 7.

Fjords, Alaska - Glacier Picture Gallery
Two Alaskan fjords still have their glaciers. Page 8.

Cirque, Montana - Glacier Picture Gallery
A cirque in Montana's Glacier National Park. Page 3.

Glacial Grooves and Polish, New York - Glacier Picture Gallery
A gneiss outcrop in New York City's Central Park is grooved and polished by ice age glaciers. Page 24.

Hanging Glaciers, Alaska - Glacier Picture Gallery
Hanging glaciers in the Chugach Mountains of Alaska. Page 9.

Horn, Switzerland - Glacier Picture Gallery
The type example of a horn is in the Swiss Alps. Page 10.

Ice Cave, Alaska - Glacier Picture Gallery
Ice cave in Guyot Glacier, southeastern Alaska. Page 12.

Ice Field, Alaska - Glacier Picture Gallery
Harding Ice Field in Kenai Fjords National Park, Alaska. Page 14.

Iceberg off Labrador - Glacier Picture Gallery
An iceberg floats in the Labrador Sea, accompanied by a whale. Page 11.

Icefall, Nepal - Glacier Picture Gallery
Icefall on the road to Everest. Geology. Page 13.

Visual Glossary of Glacial Features
Pictures of glacial features and the processes of glaciers.

Visual Glossary of Glacial Features
Pictures of glacial features and the processes of glaciers.

Visual Glossary of Glacial Features
Pictures of glacial features and the processes of glaciers.

Jokulhlaup, Alaska - Glacier Picture Gallery
Russell Fiord Bursts through the dam created by Hubbard Glacier in Alaska, 14 August 2002. Page 15.

Georgia Geologic Map
Geologic map of Georgia, part of a set of all 50 states. Page 10.

Arizona Geologic Map
Geologic map of Arizona, part of a set of all 50 states. Page 3.

Massachusetts Geologic Map
Geologic map of Massachusetts, part of a set of all 50 states. Page 21.

Maryland Geologic Map
Geologic map of Maryland, part of a set of all 50 states. Page 20.

Maine Geologic Map
Geologic map of Maine, part of a set of all 50 states. Page 19.

Michigan Geologic Map
Geologic map of Michigan, part of a set of all 50 states. Page 22.

Minnesota Geologic Map
Geologic map of Minnesota, part of a set of all 50 states. Page 23.

Missouri Geologic Map
Geologic map of Missouri, part of a set of all 50 states. Page 25.

Mississippi Geologic Map
Geologic map of Mississippi, part of a set of all 50 states. Page 24.

Montana Geologic Map
Geologic map of Montana, part of a set of all 50 states. Page 26.

North Carolina Geologic Map
Geologic map of North Carolina, part of a set of all 50 states. Page 33.

North Dakota Geologic Map
Geologic map of North Dakota, part of a set of all 50 states. Page 34.

Nebraska Geologic Map
Geologic map of Nebraska, part of a set of all 50 states. Page 27.

New Hampshire Geologic Map
Geologic map of New Hampshire, part of a set of all 50 states. Page 29.

New Jersey Geologic Map
Geologic map of New Jersey, part of a set of all 50 states. Page 30.

New Mexico Geologic Map
Geologic map of New Mexico, part of a set of all 50 states. Page 31.

Nevada Geologic Map
Geologic map of Nevada, part of a set of all 50 states. Page 28.

Ohio Geologic Map
Geologic map of Ohio, part of a set of all 50 states. Page 35.

Oklahoma Geologic Map
Geologic map of Oklahoma, part of a set of all 50 states. Page 36.

Oregon Geologic Map
Geologic map of Oregon, part of a set of all 50 states. Page 37.

Pennsylvania Geologic Map
Geologic map of Pennsylvania, part of a set of all 50 states. Page 38.

Iowa Geologic Map
Geologic map of Iowa, part of a set of all 50 states. Page 15.

Hawaii Geologic Map
Geologic map of Hawaii, part of a set of all 50 states. Page 11.

Florida Geologic Map
Geologic map of Florida, part of a set of all 50 states. Page 9.

Delaware Geologic Map
Geologic map of Delaware, part of a set of all 50 states. Page 8.

Connecticut Geologic Map
Geologic map of Connecticut, part of a set of all 50 states. Page 7.

Colorado Geologic Map
Geologic map of Colorado, part of a set of all 50 states. Page 6.

California Geologic Map
Geologic map of California, part of a set of all 50 states. Page 5.

Arkansas Geologic Map
Geologic map of Arkansas, part of a set of all 50 states. Page 4.

Alabama Geologic Map
Geologic map of Alabama, part of a set of all 50 states.

Alaska Geologic Map
Geologic map of Alaska, part of a set of all 50 states. Page 2.

Idaho Geologic Map
Geologic map of Idaho, part of a set of all 50 states. Page 12.

Illinois Geologic Map
Geologic map of Illinois, part of a set of all 50 states. Page 13.

Indiana Geologic Map
Geologic map of Indiana, part of a set of all 50 states. Page 14.

Kansas Geologic Map
Geologic map of Kansas, part of a set of all 50 states. Page 16.

Kentucky Geologic Map
Geologic map of Kentucky, part of a set of all 50 states. Page 17.

Louisiana Geologic Map
Geologic map of Louisiana, part of a set of all 50 states. Page 18.

Geologic Maps of the 50 United States
Geologic maps of all 50 U.S. states.

Geologic Maps of the 50 United States
Geologic maps of all 50 U.S. states.

Geologic Maps of the 50 United States
Geologic maps of all 50 U.S. states.

Geologic Maps of the 50 United States
Geologic maps of all 50 U.S. states.

Geologic Maps of the 50 United States
Geologic maps of all 50 U.S. states.

Current Earthquakes
Directions to information and data from earthquakes as fast as possible.

The Gold Rushes
California's was not the first nor the last of America's gold rushes.

Geologic Destinations for California Tourists
If you're going to California, be sure to put some of these geologic attractions on your must-see list.

Geology of the Appalachian Plateau
A look at the geologic history, coal production and unique attractions of the Appalachian Plateau.

Geology vs. Earth Science vs. Geoscience
While they have the exact same literal definition, Earth science, geoscience and geology can mean different things depending on who you ask.

The Lithosphere in Plate Tectonics
Everything you need to know about the lithosphere, including its composition, structure and thickness.

The Different Parts of a Stream
What are the different parts of a stream? An in-depth look at stream terminology, stream order and river valleys.

Natural Asphalt, McKittrick, California - Fossil Fuels Photo Essay
Asphalt is a tarry variety of the fossil fuel petroleum. Page 17.

Crude Oil Seep, McKittrick, California - Fossil Fuels Photo Essay
Natural seeps of crude oil were the first source of this fossil fuel. Page 16.

Oil Gusher - Fossil Fuels Photo Essay
Oil gushers are famous incidents in the history of fossil fuel. Page 20.

Oil Sand, Alberta - Fossil Fuels Photo Essay
Oil sand or tar sand is a major fossil fuel. Page 23.

Oil Sand Excavator - Fossil Fuels Photo Essay
Huge excavating machines are used in oil sand mines to extract this fossil fuel. Page 25.

Oil Sand Mine, Alberta - Fossil Fuels Photo Essay
Oil sand is a fossil fuel that is processed much like coal. Page 26.

Oil Sand Outcrop, Alberta - Fossil Fuels Photo Essay
Oil sand rocks exposed near Fort McMurray, Alberta. Page 24.

Oil Shale Waste Piles, Scotland - Fossil Fuels Photo Essay
Waste from oil shale operations is a major problem with this fossil fuel. Page 30.

Oil Shale Quarry, Virginia - Fossil Fuels Photo Essay
A former oil shale quarry in Virginia. Page 28.

Oil Shale Retort, England - Fossil Fuels Photo Essay
Oil shale is subject to boom and bust, depending on competing fossil fuels. Page 29.

Oil Shale Specimen, Germany - Fossil Fuels Photo Essay
A hand specimen of oil shale, a major fossil fuel. Page 27.

Peat Bog, Canada - Fossil Fuels Photo Essay
Peat bogs are the source of peat, often considered a fossil fuel. Page 31.

Burning Peat - Fossil Fuels Photo Essay
The fossil fuel peat burns in the domestic fireplace. Page 34.

Peat Turfs - Fossil Fuels Photo Essay
Peat is a fossil fuel that must be slowly dried before use. Page 33.

Peat Production, Ireland - Fossil Fuels Photo Essay
Ireland is a leading producer of the fossil fuel peat. Page 32.

Oil Museum, Texas - Fossil Fuels Photo Essay
Oil museums celebrate this fossil fuel. Page 22.

Star Oil Company, an Early Oil Refinery, California - Fossil Fuels Photo Essay
The first oil refineries arose with the earliest wells. Page 19.

Chimaera Gas Seep, Turkey - Fossil Fuels Photo Essay
Flaming gas seeps are a dramatic instance of this fossil fuel. Page 10.

Cardiff Coal Exchange - Fossil Fuels Photo Essay
The Cardiff Coal Exchange was a seat of wealth in the days of King Coal. Page 4.

Coaling Tower, Michigan - Fossil Fuels Photo Essay
An old coaling tower stands witness to coal, the fossil fuel that once drove most transportation. Page 5.

Coal Monument, Australia - Fossil Fuels Photo Essay
A coal monument in Australia honors the role in history of this fossil fuel. Page 8.

Coal-Fired Power Plant, Germany - Fossil Fuels Photo Essay
Coal is the foremost fossil fuel used to generate electricity. Page 6.

Coal Outcrop, Pennsylvania - Fossil Fuels Photo Essay
Coal is exposed in outcrop near Allentown, Pennsylvania.

Coal Seller, Egypt - Fossil Fuels Photo Essay
Coal is still a widely used fossil fuel for domestic purposes. Page 7.

Shipping Coal, Virginia - Fossil Fuels Photo Essay
Coal is exported from the United States by ship. Page 3.

Crude Oil, California - Fossil Fuels Photo Essay
Crude oil, shown here on a California beach, is a widely disseminated fossil fuel. Page 15.

Lignite Coal Mine, Germany - Fossil Fuels Photo Essay
Lignite coal is a widely used fossil fuel. Page 2.

Gas Flare, North Dakota - Fossil Fuels Photo Essay
Gas flares are a common waste of this fossil fuel. Page 11.

Gas Hydrate or Methane Hydrate, Eastern Pacific Sea Floor - Fossil Fuels Photo Essay
Gas hydrate or methane ice is a promising fossil fuel. Page 13.

Gas Hydrate, Alaska North Slope - Fossil Fuels Photo Essay
Methane ice could supplant oil as Alaska's major fossil fuel. Page 14.

Gas Seep, Los Angeles - Fossil Fuels Photo Essay
Natural gas bubbles up through an estuary in Los Angeles. Page 9.

Gas Well, Alberta - Fossil Fuels Photo Essay
Gas production practices make it the cleanest fossil fuel. Page 12.

Oil Refinery, Iraq - Fossil Fuels Photo Essay
Every industrialized country has oil refineries for this fossil fuel. Page 21.

Borax - Evaporite/Halide Minerals
Borax is one of the evaporite minerals.

Gypsum - Evaporite/Halide Minerals
Gypsum is one of the evaporite minerals. Page 3.

Fluorite - Evaporite/Halide Minerals
Fluorite is one of the halide minerals. Page 2.

Halite - Evaporite/Halide Minerals
Halite is one of the halide minerals. Page 4.

Sylvite - Evaporite/Halide Minerals
Sylvite is one of the halide minerals. Page 5.

Ulexite - Evaporite/Halide Minerals
Ulexite is one of the evaporite minerals. Page 6.

Beacon Rock - Washington State Geological Attractions and Destinations
Beacon Rock is one of Washington state's geologic attractions.

Drumheller Channels - Washington State Geological Attractions and Destinations
Drumheller Channels are one of Washington state's geologic attractions. Page 2.

Flaming Geyser - Washington State Geological Attractions and Destinations
Flaming Geyser is one of Washington state's geologic attractions. Page 3.

Ginkgo Petrified Forest - Washington State Geological Attractions and Destinations
Ginkgo Petrified Forest is one of Washington state's geologic attractions. Page 4.

Grand Coulee - Washington State Geological Attractions and Destinations
Grand Coulee is one of Washington state's geologic attractions. Page 5.

Lime Kiln Point - Washington State Geological Attractions and Destinations
Lime Kiln Point is one of Washington state's geologic attractions. Page 6.

Mima Mounds - Washington State Geological Attractions and Destinations
Mima Mounds Preserve is one of Washington state's geologic attractions. Page 7.

Mount Rainier - Washington State Geological Attractions and Destinations
Mount Rainier is one of Washington state's geologic attractions. Page 8.

Mount St. Helens - Washington State Geological Attractions and Destinations
Mount St. Helens is one of Washington state's geologic attractions. Page 9.

Peshastin Pinnacles - Washington State Geological Attractions and Destinations
Peshastin Pinnacles is one of Washington state's geologic attractions. Page 10.

Steptoe and Kamiak Buttes - Washington State Geological Attractions and Destinations
Steptoe and Kamiak Buttes are one of Washington state's geologic attractions. Page 11.

Wallula Gap - Washington State Geological Attractions and Destinations
Wallula Gap is one of Washington state's geologic attractions. Page 12.

Alibates Flint Quarries - Texas Geological Attractions and Destinations
Alibates Flint Quarries is one of Texas' geological attractions.

Caprock Canyons - Texas Geological Attractions and Destinations
Caprock Canyons is one of Texas' geological attractions. Page 3.

Dinosaur Valley - Texas Geological Attractions and Destinations
Dinosaur Valley is one of Texas' geological attractions. Page 4.

Enchanted Rock - Texas Geological Attractions and Destinations
Enchanted Rock is one of Texas' geological attractions. Page 5.

Guadalupe Mountains - Texas Geological Attractions and Destinations
The Guadalupe Mountains are one of Texas' geological attractions. Page 6.

Longhorn Cavern - Texas Geological Attractions and Destinations
Longhorn Cavern is one of Texas' geological attractions. Page 7.

Monahans Sandhills - Texas Geological Attractions and Destinations
Monahans Sandhills is one of Texas' geological attractions. Page 8.

Odessa Meteor Crater - Texas Geological Attractions and Destinations
Odessa Meteor Crater is one of Texas' geological attractions. Page 9.

Padre Island - Texas Geological Attractions and Destinations
Padre Island is one of Texas' geological attractions. Page 10.

Sierra Madera Astrobleme - Texas Geological Attractions and Destinations
Sierra Madera Astrobleme is one of Texas' geological attractions. Page 11.

Solitario Uplift - Texas Geological Attractions and Destinations
The Solitario Uplift is one of Texas' geological attractions. Page 12.

Devil's Backbone - Virginia Geological Attractions and Destinations
Devil's Backbone is one of Virginia's geological attractions.

First Landing Dunes - Virginia Geological Attractions and Destinations
The dunes of First Landing Park are one of Virginia's geological attractions. Page 2.

Mountain Lake - Virginia Geological Attractions and Destinations
Mountain Lake is one of Virginia's geological attractions. Page 5.

Mount Rogers - Virginia Geological Attractions and Destinations
Mount Rogers is one of Virginia's geological attractions. Page 9.

Washington DC Geology - Marble of the Washington Monument
Weathered and repaired marble of the Washington Monument in Washington, DC. Page 7.

Washington DC Geology - Chesapeake & Ohio Canal in Georgetown
The Chesapeake and Ohio Canal in Washington, DC. Page 10.

Washington DC Geology - Granite Wall at the FDR Memorial
The Franklin Roosevelt Memorial is a geologic highlight of Washington, DC. Page 11.

Washington DC Geology - Marble Columns, Jefferson Memorial
Marble is the foremost stone of Washington, DC. Page 3.

Washington DC Geology - Smithsonian Institution Headquarters
The Smithsonian's red sandstone headquarters is a geologic highlight of Washington, DC. Page 8.

Washington DC Geology - Washington Monument Imperfections
The Washington Monument is as imperfect as its eponym. Page 6.

Official State Minerals of the United States - Babingtonite - State Mineral of Massachusetts
Black, glossy babingtonite is the state mineral of Massachusetts. Page 2.

Official State Minerals of the United States - Bowenite - State Mineral of Rhode Island
Bowenite, a serpentine mineral, is the state mineral of Rhode Island. Page 4.

Official State Minerals of the United States - Coal - State Mineral of Kentucky
Coal is the state mineral (sic) of Kentucky. Page 5.

Official State Minerals of the United States - Copper - State Mineral of Utah
Copper is the state mineral of Utah. Page 6.

Official State Minerals of the United States - Fluorite - State Mineral of Illinois
Fluorite is the state mineral of Illinois. Page 7.

Official State Minerals of the United States - Galena - State Mineral of Missouri and Wisconsin
Galena is the state mineral of Missouri and Wisconsin. Page 8.

Official State Minerals of the United States - Gold - State Mineral of Alaska and California
Gold is the state mineral of Alaska and California. Page 9.

Official State Minerals of the United States - Quartz - State Mineral of Arkansas
Quartz is the state mineral of Arkansas. Page 11.

Official State Minerals of the United States - Rose Quartz - State Mineral of South Dakota
Rose quartz is the state mineral of South Dakota. Page 13.

Official State Minerals of the United States - Silver - State Mineral of Nevada
Silver is, by implication, the state mineral of Nevada. Page 15.

Official State Minerals of the United States - Talc - State Mineral of Vermont
Talc is the state mineral of Vermont. Page 17.

Igneous Rock Textures - Aphanitic Texture
Aphanitic rocks have mostly invisible mineral grains.

Igneous Rock Textures - Equigranular Texture
Rocks with equigranular texture have grains the same size. Page 2.

Igneous Rock Textures - Phaneritic Texture
Phaneritic rocks have visible mineral grains. Page 4.

Igneous Rock Textures - Porphyritic Texture
Rocks with porphyritic texture have larger grains in a matrix of smaller grains. Page 6.

Igneous Rock Textures - Spinifex Texture
Rocks with spinifex texture are full of long needlelike crystals. Page 8.

Peridotite Fresh and Weathered, California - Pictures of Peridotite
Peridotite outcrop showing fresh and weathered surface. Page 2.

Magnetite Crystals in Altered Peridotite, Greece - Pictures of Peridotite
Peridotite is very rich in iron. Geology. Page 4.

Desert Pavement Near Blythe, California - Desert Pavement Gallery
A heavily varnished, ancient desert pavement surface. Page 9.

Old Desert Pavement Near Blythe, California - Desert Pavement Gallery
Closeup of the ancient, heavily varnished desert pavement near Blythe, California. Page 8.

Spring Flowers in Desert Pavement - Desert Pavement Gallery
Desert pavement can help retain moisture in the soils beneath it. Page 3.

Rock Varnish in a Cobble from Desert Pavement - Desert Pavement Gallery
Rock varnish or desert varnish is common on desert pavement. Page 2.

Dinosaur Ridge - Geology of Golden, Colorado
Headquarters of the Dinosaur Ridge geological site, west of Denver. Page 9.

Aerial Overview of Golden - Geology of Golden, Colorado
Aerial overview of the Golden area, west of Denver.

North Table Mountain - Geology of Golden, Colorado
North Table Mountain in the Golden area, west of Denver. Page 3.

Geology of Golden, Colorado - POGI Site Stratigraphy
Profile of the Point of Geological Interest site west of Denver. Page 6.

Paleosol at the Point of Geological Interest or POGI - Geology of Golden, Colorado
Paleosol in the I-70 roadcut, west of Denver. Page 7.

Liesegang Structure at the POGI Site - Geology of Golden, Colorado
Liesegang structure in sandstone at the POGI site, west of Denver. Page 8.

Red Rocks Park - Geology of Golden, Colorado
Red Rocks Park is a geologic highlight of the Golden area, west of Denver. Page 10.

Uranium Roll-Front Deposit - Geology of Golden, Colorado
A small uranium roll-front crops out in a roadcut south of Golden, Colorado. Page 11.

Uranium Minerals in a Roll-Front Deposit - Geology of Golden, Colorado
Uranium minerals in a roll-front deposit west of Denver. Page 12.

South Table Mountain - Geology of Golden, Colorado
South Table Mountain in the Golden area, west of Denver. Page 2.

Triceratops Trail, Golden - Geology of Golden, Colorado
Gas-escape structures in the Triceratops Trail fossil park in the Golden area, west of Denver. Page 4.

Fossils of Triceratops Trail, Golden Colorado - Raindrop Impressions
Raindrop impressions are among the fossils preserved for Golden's citizens. Page 8.

Geology of the Las Vegas Region - Las Vegas Rocks
Las Vegas is decorated with boulders of all kinds. Page 3.

Geology of the Las Vegas Region - Gypsum
Gypsum is common in the rocks around Las Vegas. Page 11.

Geology of the Las Vegas Region - Keystone Thrust
The Keystone Thrust is a highlight of Las Vegas geology. Page 7.

Geology of the Las Vegas Region - Geologic Map of the Las Vegas Area
A schematic geologic map of the Las Vegas area. Page 2.

Upper Las Vegas Wash, Nevada - Wash Gravels
Gravel is the typical sediment at Upper Las Vegas Wash. Page 4.

Upper Las Vegas Wash, Nevada - Freshwater Snail Fossil
A Quaternary gastropod from Upper Las Vegas Wash. Page 8.

Sevier Thrust Belt in Nevada - Keystone Thrust
The Keystone Thrust is west of Las Vegas, Nevada.

Sevier Thrust Belt in Nevada - Valley of Fire
Valley of Fire in southern Nevada is related to the Sevier thrust belt. Page 7.

Geology of Valley of Fire State Park, Nevada
The Aztec Sandstone displays crossbedding in this spectacular desert park northeast of Las Vegas.

Entrance to Valley of Fire State Park, Nevada
Red rocks of the Aztec Sandstone are the first thing you see in this park northeast of Las Vegas. Page 2.

Valley of Fire State Park, Nevada - Cambrian Cliffs
Gray Cambrian limestone looms over this desert park northeast of Las Vegas. Page 3.

Valley of Fire State Park, Nevada - Petroglyph Canyon
Red rocks of the Aztec Sandstone line the walls of Petroglyph Canyon in Valley of Fire State Park, Nevada. Page 6.

Valley of Fire State Park, Nevada - Tafoni
Tafoni in the red rocks of the Aztec Sandstone at Valley of Fire State Park, Nevada. Page 10.

Valley of Fire State Park, Nevada - Desert Varnish
Red rocks of the Aztec Sandstone display desert varnish in Valley of Fire State Park, Nevada. Page 11.

Igneous Rock Textures - Glassy or Hyaline Texture
Glassy rocks have no or almost no grains. Page 3.

Igneous Rock Textures - Pyroclastic Texture
Rocks with pyroclastic texture are made of pieces of volcanic material. Page 7.

Igneous Rock Textures - Vesicular Texture
Rocks with vesicular texture are full of bubbles. Page 9.

Precious Stone Optical Special Effects - Asterism in Corundum
Asterism in a star sapphire. Geology.

Precious Stone Optical Special Effects - Chatoyancy in Quartz
Chatoyancy in a tiny quartz catseye earring. Page 2.

Precious Stone Optical Special Effects - Fire in Diamond
Fire, or colored refractions, in diamond. Page 3.

Precious Stone Optical Special Effects - Fluorescence in Fluorite
Fluorite fluoresces purple under ultraviolet light. Page 4.

Precious Stone Optical Special Effects - Iridescence in Seashell
Iridescence displayed in the abalone insets of a Venice Beach sidewalk. Page 5.

Precious Stone Optical Special Effects - Schiller in Opal
An opal stud displays schiller in sunlight. Page 8.

Dinosaur Ridge, Morrison, Colorado - Ripples in the Dakota Group
Ripple marks at Dinosaur Ridge National Natural Landmark near Denver, Colorado.

Fossils of Triceratops Trail, Golden Colorado - Palm Leaves
Fine palm-leaf fossils are preserved at Triceratops Trail. Page 5.

SAFOD - First Core Section
A section of core from the SAFOD drilling project is readied for opening. Page 6.

SAFOD - Cleaning the Cores
Cores are cleaned from the SAFOD drilling project. Page 9.

SAFOD - Slickensides in Fault Gouge
Slickensides mark the shaly gouge from SAFOD cores across an active earthquake fault. Page 13.

SAFOD - Core Under Glass
A core sample from the SAFOD project is displayed at a press event. Page 12.

SAFOD - Opening the First Core
Geologists prepare to open the first cores into an active earthquake fault. Page 7.

SAFOD - The First Sample
Core-catcher sample is the first fruit of the SAFOD drilling project. Page 8.

SAFOD - Geologic Cross Section
Geologic section of the SAFOD drilling project into an active earthquake fault. Page 2.

SAFOD - Retrieving the Core
A SAFOD worker pulls a core barrel from a hole drilled into an active earthquake fault. Page 4.

Geology of San Francisco, California - Alcatraz Island
Alcatraz Island is one of San Francisco's geologic attractions. Page 5.

Geology of San Francisco, California - Baker Beach
Baker Beach is one of San Francisco's geologic attractions. Page 22.

Geology of San Francisco, California - Bernal Hill
Bernal Hill is one of San Francisco's geologic attractions. Page 12.

Geology of San Francisco, California - Dunes of Ocean Beach
Ancient sand dunes are one of San Francisco's geologic attractions. Page 3.

Geology of San Francisco, California - Elk Glen Lake, San Francisco
Elk Glen Lake is one of San Francisco's geologic attractions. Page 2.

Geology of San Francisco, California - Boulder Bridge, Stow Lake, Golden Gate Park
The rustic stone bridge at Stow Lake is one of San Francisco's geologic attractions. Page 7.

Geology of San Francisco, California - Chert at Grand View Park
Grand View Park is one of San Francisco's geologic attractions. Page 11.

Geology of San Francisco, California - Outcrop at Lakeview-Ashton Minipark
Lakeview-Ashton Minipark's outcrop is one of San Francisco's geologic attractions. Page 13.