What Does a Geologist Do? Information and two videos about the relevance of geology today.
Troglobites are creatures that have adapted to a permanent life in the darkness of a cave.
||Geologic Time Scale
Divisions of Geologic Time USGS periodically revises rock unit names and age estimates.
Rocks Galleries of igneous, sedimentary and metamorphic rock photos with descriptions.
|What Are Minerals?
Minerals are the building blocks of our society. We use items made with them every day.
||What Is Earth Science?
What Is Earth Science? The study of Earth and its neighbors in space. Learn more!
||Great Rift Valley
The East Africa Rift System Learn about the complex East Africa Rift Valley system.
Plate Tectonics Articles, theory, plate diagrams, plate maps and teaching ideas.
Sliding Rocks - Racetrack Playa How these rocks slide across a dry lake bed is a mystery.
||Gold History and Uses
Gold A history of gold uses, mining and prospecting over thousands of years.
||Diamonds from Coal?
Diamonds from Coal? They form under several conditions that rarely involve coal.
||Maps Of Pangaea
Pangaea Maps A sequence of maps shows how a large supercontinent fragmented.
Salt Glaciers are masses of salt that flow downslope under their own weight.
||What is a Geyser?
What is a Geyser? Photos of geysers from around the world. Causes, height and more.
Geology Tools Available are pick, chisel and crack hammers, rock chisels, goggles and more.
Salt Domes are columns of salt that move upwards because of the salt\'s low specific gravity.
Volcanos Articles about volcanoes, volcanic hazards and eruptions past and present.
How Do Snowflakes Form? They grow from a tiny particle but they might not reach the Earth.
Bear Attacks Knowing how to react to a bear encounter and attack could save your life.
||What is a Maar?
What is a Maar? The second most common volcanic landscape feature on Earth.
Landslides A USGS fact sheet about landslides and events that trigger them.
||Rare Earth Elements
REEs Special metals used in cell phones, DVDs, batteries, magnets & many other products.
Roadside Geology Guides Learn about the Geology of your favorite state as seen from the road.
||San Andreas Fault
What is the San Andreas Fault? Map, photos and description of the fault by Dr. David Lynch.
The Geology of Bottled Water It costs 1000x as much as tap water. What are you getting?
How Old is the Grand Canyon? Wayne Ranney explores the age of the Grand Canyon.
||Green River Fossils
Spectacular Fossils of the Green River Formation. Some of the world\'s best fossil fish.
||Air Bubbles in Amber
Bubbles in Amber Cretaceous oxygen levels determed from air bubbles trapped in amber.
|What is a Hydrograph?
What is a Hydrograph? Charts that display the change of a hydrologic variable over time.
Yosemite Glaciers There are two active glaciers in Yosemite - but they are slowly melting away.
The Selenga River delivers most of the water to Lake Baikal, the largest lake in the world.
Stream Gaging Stations Used by hydrologists to monitor streams or other water bodies.
Homeowner\'s Insurance and Geologic Hazards Most policies do not cover geologic hazards.