Updated Articles and Resources
- What Is an Ophiolite?Created: 2009-11-06 @ 20:55:10 EST Updated: 2009-11-06 @ 21:03:40 EST
Not a rock type, it's a whole assemblage of crustal rocks… - Mineral Collecting at Contact Zones - What to Look For in Country Ro…Created: 2009-11-05 @ 14:29:24 EST
For mineral opportunities, be aware of contact zones… - Peridotite Gallery - Pictures of PeridotiteCreated: 2009-11-03 @ 17:00:30 EST Updated: 2009-11-03 @ 18:33:34 EST
See peridotite in the hand and in the landscape… - Chabazite - The Zeolite MineralsCreated: 2009-10-30 @ 13:00:22 EDT
Chabazite is one of the common zeolite minerals… - Heulandite - The Zeolite MineralsCreated: 2009-10-30 @ 13:00:11 EDT
Heulandite is one of the common zeolite minerals… - Laumontite - The Zeolite MineralsCreated: 2009-10-30 @ 13:00:01 EDT
Laumontite is one of the common zeolite minerals… - Natrolite - The Zeolite MineralsCreated: 2009-10-30 @ 12:59:50 EDT
Natrolite is one of the common zeolite minerals… - Stilbite - The Zeolite MineralsCreated: 2009-10-30 @ 12:59:39 EDT
Stilbite is one of the common zeolite minerals… - Analcime (Analcite) - The Zeolite MineralsCreated: 2009-10-30 @ 12:59:15 EDT
Analcime is one of the common zeolite minerals… - Geology Biographies and the Parade of HeroesCreated: 2009-10-15 @ 23:50:35 EDT
Enjoy your geologists now, because you won't recognize them once they're history… - Farm North of Sutter Buttes, California Created: 2009-09-21 @ 00:16:52 EDT Updated: 2009-09-21 @ 00:50:53 EDT
Farm country near the Sutter Buttes of central California, 'the world's smallest mountain range.'… - West Side of the Sutter Buttes, California Created: 2009-09-21 @ 00:16:25 EDT Updated: 2009-09-21 @ 00:51:11 EDT
West side of the Sutter Buttes of central California, 'the world's smallest mountain range.'… - Rampart, North Side of Sutter Buttes, California …Created: 2009-09-21 @ 00:16:06 EDT
View from the north of the volcanic rampart of the Sutter Buttes… - Chisel-Tip Rock Pick - Rock HammersCreated: 2009-09-20 @ 22:56:55 EDT Updated: 2009-09-20 @ 23:04:36 EDT
An antique hammer of uncommon style… - Zeolites - The Silicate MineralsCreated: 2009-09-18 @ 13:36:51 EDT Updated: 2009-09-18 @ 13:52:59 EDT
The great majority of rocks are made of silicate minerals… - The Zeolite MineralsCreated: 2009-09-18 @ 13:30:15 EDT Updated: 2009-09-18 @ 13:30:15 EDT
A cryptic and important group of low-temperature minerals… - Crysts, Blasts and Clasts - Large Particles in RocksCreated: 2009-09-16 @ 23:37:15 EDT Updated: 2009-09-16 @ 23:43:50 EDT
There's a welter of terminology for large particles in various types of rocks… - Where Were You During the Loma Prieta QuakeCreated: 2009-09-10 @ 20:54:54 EDT Updated: 2009-09-11 @ 12:42:18 EDT
Share your story from the 1989 Loma Prieta Earthquake… - Where to Look for Rocks and MineralsCreated: 2009-08-27 @ 18:22:50 EDT
Rocks and minerals can be found everywhere, but there is a learning process involved… - Metamorphic MineralsCreated: 2009-08-22 @ 00:12:10 EDT
Minerals forming in solid rocks under prolonged heat and pressure… - Evaporite MineralsCreated: 2009-08-22 @ 00:07:13 EDT
Minerals typically formed in evaporitic settings… - Hydrothermal Vein MineralsCreated: 2009-08-22 @ 00:01:55 EDT
Minerals formed during injection of deep hot fluids and pegmatite formation… - Diagenetic MineralsCreated: 2009-08-21 @ 23:56:51 EDT
Minerals that form during the consolidation of a rock from sediment… - Primary MineralsCreated: 2009-08-21 @ 23:49:13 EDT
Minerals that form during the solidification of a melt… - Scientific ObservationCreated: 2009-08-13 @ 17:46:17 EDT Updated: 2009-08-13 @ 17:53:14 EDT
Scientific observation is a refined version of an everyday skill… - Sinkhole, Oman - Erosional Landform PicturesCreated: 2009-08-10 @ 17:03:56 EDT Updated: 2009-08-10 @ 17:04:16 EDT
Sinkholes are a widespread erosional landform type… - Arroyo, Nevada - Erosional Landform PicturesCreated: 2009-08-05 @ 19:58:24 EDT Updated: 2009-08-05 @ 19:58:41 EDT
Arroyos are dry, steep-walled streambeds… - Monadnock, New Hampshire - Erosional Landform PicturesCreated: 2009-08-05 @ 19:49:23 EDT Updated: 2009-08-05 @ 19:49:40 EDT
Monadnocks are erosional landforms… - Cliff, New York - Erosional Landform PicturesCreated: 2009-08-05 @ 19:43:30 EDT Updated: 2009-08-05 @ 19:43:48 EDT
Cliffs are erosional landforms… - Ravine, Finland - Erosional Landform PicturesCreated: 2009-08-05 @ 19:12:34 EDT Updated: 2009-08-05 @ 19:30:48 EDT
Ravines are a basic erosional landform type… - Gulch, California - Erosional Landform PicturesCreated: 2009-08-05 @ 19:10:45 EDT Updated: 2009-08-05 @ 19:31:21 EDT
Gulches are an erosional landform type, a kind of ravine… - Gorge, Texas - Erosional Landform PicturesCreated: 2009-08-05 @ 19:08:32 EDT Updated: 2009-08-05 @ 19:31:14 EDT
Gorges are erosional landform types, a type of ravine… - Cirque, California - Erosional Landform PicturesCreated: 2009-08-04 @ 23:29:35 EDT Updated: 2009-08-04 @ 23:41:31 EDT
Cirques are mountaiside bowls carved by glacial erosion… - Hummocky Cross-Bedding, Utah - Pictures of Sedimentary StructuresCreated: 2009-08-03 @ 20:16:35 EDT Updated: 2009-08-03 @ 20:16:53 EDT
Hummocky cross-bedding in sedimentary rocks is a sign of ancient storms… - Scour-and-Fill Structures, California - Pictures of Sedimentary Stru…Created: 2009-08-03 @ 19:31:46 EDT Updated: 2009-08-03 @ 19:32:09 EDT
Scour-and-fill structures are signs of geologic history in sedimentary rocks. … - Stromatolitic Structure, Mongolia - Pictures of Sedimentary Structur…Created: 2009-08-03 @ 19:11:47 EDT Updated: 2009-08-03 @ 19:12:06 EDT
Bacteria or algae may leave stromatolitic structure in sedimentary rocks. … - Bedding, California - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:06:17 EDT
Bedding is the most common feature of sedimentary rocks… - Channel Cast, California - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:05:49 EDT
Channel casts are common sedimentary features in turbidites… - Concretions, Nevada - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:05:35 EDT
Concretions are a widespread sedimentary structure… - Convolute Lamination, California - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:05:09 EDT
Convolute lamination disturbs the bedding of sedimentary rocks… - Flame Structure, California - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:04:53 EDT
Flame structure helps indicate gravity and current directions in sedimentary rocks… - Foreset Beds, Australia - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:04:32 EDT
Foreset beds are laid down on a sloping surface… - Gas-Escape Structures, Colorado - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:03:52 EDT
Marks made by bubbles rising through sediment beds… - Geopetal Structure, Wisconsin - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:03:33 EDT
Geopetal structures are a reliable indicator of the horizontal direction in sedimentary rocks… - Graded Bedding, California - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:03:06 EDT
Graded bedding helps determine the vertical direction in sedimentary rocks… - Imbrication, Nevada - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:02:53 EDT
Imbrication is a stacking of grains according to the current… - Lamination, California - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:02:38 EDT
Lamination is the fine layering typical of many sedimentary rocks… - Linear Ripples, New York - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:02:23 EDT
Ripples are commonly preserved in sedimentary rocks… - Load Casts, California - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:02:00 EDT
Load casts form where heavy sediments press down on soft sediments… - Mudcracks, California - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:01:31 EDT
Mudcracks are a sure sign of subaerial exposure… - Rip-Up Clasts, California - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 20:01:10 EDT
Rip-up clasts in sedimentary rocks are signs of subsea avalanches… - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 19:59:42 EDT Updated: 2009-07-29 @ 19:59:42 EDT
Signs of geologic history in sedimentary rocks. … - Flute Casts, Mongolia - Pictures of Sedimentary StructuresCreated: 2009-07-29 @ 19:57:13 EDT Updated: 2009-07-29 @ 19:58:03 EDT
Flute casts are widespread signs of geologic history in sedimentary rocks. … - Types of Volcanoes - Tuff Cone, OregonCreated: 2009-07-24 @ 21:04:00 EDT Updated: 2009-07-24 @ 21:04:37 EDT
Tuff cones are one of the volcano types found on land… - Mud Volcano, California - Depositional Landform PicturesCreated: 2009-07-24 @ 20:46:38 EDT Updated: 2009-07-24 @ 20:47:06 EDT
Mud volcanoes are classified as depositional landforms… - Mud Volcano, California - Depositional Landform PicturesCreated: 2009-07-24 @ 20:43:26 EDT Updated: 2009-07-24 @ 20:43:55 EDT
Mud volcanoes of all sizes are depositional landforms… - Lava Flow, Oregon - Depositional Landform PicturesCreated: 2009-07-24 @ 20:06:26 EDT Updated: 2009-07-24 @ 20:06:50 EDT
Lava flows can be classified as depositional landforms… - Stream Offset, California - Tectonic LandformsCreated: 2009-07-24 @ 16:01:57 EDT Updated: 2009-07-24 @ 16:05:23 EDT
Stream offsets are common signs of fault movement… - Shutter Ridge, California - Tectonic LandformsCreated: 2009-07-24 @ 16:00:28 EDT Updated: 2009-07-24 @ 16:05:39 EDT
Shutter ridges are common tectonic landforms along transcurrent faults… - Sag Basin, California - Tectonic LandformsCreated: 2009-07-24 @ 15:57:55 EDT Updated: 2009-07-24 @ 16:04:51 EDT
Sag basins are tectonic landforms found along transcurrent faults… - Rift Valley, Uganda-Congo - Tectonic LandformsCreated: 2009-07-24 @ 15:52:34 EDT Updated: 2009-07-24 @ 16:04:33 EDT
Rift valleys are among the largest tectonic landforms… - Pressure Ridge, California - Tectonic LandformsCreated: 2009-07-24 @ 15:50:29 EDT Updated: 2009-07-24 @ 16:04:12 EDT
Pressure ridges are common tectonic landforms along transcurrent faults… - Fault Scarp, California - Tectonic LandformsCreated: 2009-07-24 @ 15:48:10 EDT Updated: 2009-07-24 @ 17:25:25 EDT
Fault scarps are a type of tectonic landform… - Escarpment, Oregon - Tectonic LandformsCreated: 2009-07-24 @ 15:46:10 EDT Updated: 2009-07-24 @ 16:02:30 EDT
The largest escarpments are tectonic landforms… - Tectonic LandformsCreated: 2009-07-24 @ 15:07:28 EDT Updated: 2009-07-24 @ 16:06:17 EDT
Common types of tectonic landforms… - Slickensides or Fault Mirrors - Closeup of Basalt SlickensideCreated: 2009-07-20 @ 19:12:00 EDT Updated: 2009-07-20 @ 23:54:54 EDT
Closeup of the fault-polished rock surface of a San Quentin basalt outcrop… - Slickensides or Fault Mirrors - Slickenside in BasaltCreated: 2009-07-20 @ 19:08:24 EDT Updated: 2009-07-20 @ 23:54:41 EDT
Slickenside in a basalt outcrop, Marin County California… - Obsidian Picture Gallery - Spherulites in ObsidianCreated: 2009-07-14 @ 23:04:37 EDT Updated: 2009-07-14 @ 23:04:56 EDT
Spherulites are balls of minerals that occur in obsidian… - Obsidian Picture Gallery - Spherulites in ObsidianCreated: 2009-07-14 @ 20:07:31 EDT Updated: 2009-07-14 @ 23:05:27 EDT
Obsidian may contain 'bubbles' of mineral matter called spherulites. … - About Geology - Geology BasicsUpdated: 2009-11-06 @ 00:58:38 EST
Whatever your interest is in geology, here's where to start learning about it… - The Strangelove OceanUpdated: 2009-11-06 @ 00:54:14 EST
Strangelove oceans are nasty things no matter what they really are… - Look to the Skies! - Cosmic ImpactsUpdated: 2009-11-06 @ 00:52:39 EST
Research on cosmic impacts has made us take a big gulp and thank our lucky stars… - Explore Geology - Learn MoreUpdated: 2009-11-06 @ 00:43:00 EST
Get involved more deeply and personally in geology-related activities… - Quakes and Other Events - Geological Phenomena…Updated: 2009-11-06 @ 00:38:52 EST
Geological events like earthquakes and volcanic eruptions are always newsworthy… - Mohs Hardness ScaleUpdated: 2009-11-05 @ 18:37:36 EST
The ten-mineral Mohs scale of relative hardness, based on what scratches what… - Asbestos in a NutshellUpdated: 2009-11-05 @ 18:23:08 EST
This mineral resource has been first a boon, then a bane in its century of commercial existence… - Earth's Formation in a NutshellUpdated: 2009-11-05 @ 18:17:27 EST
The straight story of how Earth began, as today's geologists tell it… - The World versus the Earth: Creation and CreationismUpdated: 2009-11-05 @ 18:11:33 EST
Genesis or geology? The foundation of the world versus the origin of the Earth… - Famous StonesUpdated: 2009-11-05 @ 17:46:47 EST
Real rock stars from around the world, from Plymouth Rock to the Blarney Stone to the Black Stone of the Ka'aba… - Jupiter's Moon Io, the Real Volcano WorldUpdated: 2009-11-05 @ 17:34:34 EST
What does Jupiter's amazing moon Io teach us about Earth?… - Types of Types - About Geologic Type SpecimensUpdated: 2009-11-05 @ 17:10:47 EST
When geologists need some sort of precise standard for imprecise things, they revert to type--type specimens, that is… - The Web-Wide WorldUpdated: 2009-11-05 @ 14:51:18 EST
Digital Earth combines enormous amounts of data in a geographically organized database… - Fossils of Triceratops Trail, Golden Colorado…Updated: 2009-11-05 @ 14:48:40 EST
Dinosaur tracks and other fine fossils are preserved for Golden's citizens… - The Still Small Voice of WIMPs - Underground LaboratoriesUpdated: 2009-11-05 @ 14:34:41 EST
When searching for WIMPs, scientists seek the quietest places deep underground… - Why You Should Vote for GeologistsUpdated: 2009-11-05 @ 14:31:00 EST
The best person for the job may well be a geologist… - Jökulhlaups - Glacial Outburst FloodsUpdated: 2009-11-05 @ 12:56:34 EST
Jökulhlaups are peculiar glacial floods, as impressive as the people who live with them… - Seismic Hazard Map, ChinaUpdated: 2009-11-03 @ 20:59:04 EST
The China part of the Global Seismic Hazard Map of 1999… - Aftershocks Are Not AfterthoughtsUpdated: 2009-11-03 @ 19:49:19 EST
Aftershocks can be nasty surprises, even worse than the main event… - Toward a National Geologic TrailUpdated: 2009-11-02 @ 23:52:22 EST
America's biggest flood may become its biggest virtual park… - Lakeview Gusher - View Out the HorseshoeUpdated: 2009-10-27 @ 23:19:36 EDT
The scene from the scene of the great gusher of 1910… - Lakeview Gusher - Asphalt Lake BedsUpdated: 2009-10-27 @ 23:19:28 EDT
Silt combines with crude oil at the Lakeview gusher site… - Lakeview Gusher - Asphalt FlowsUpdated: 2009-10-27 @ 23:19:11 EDT
Crude oil mimicked lava during the 1910 Lakeview gusher and afterwards… - Lakeview Gusher - Asphalt on the RampartsUpdated: 2009-10-27 @ 23:19:02 EDT
Asphalt and sand top the berm at the Lakeview gusher site… - Lakeview Gusher - Retaining WallUpdated: 2009-10-27 @ 23:18:55 EDT
Visit the site of America's most spectacular oil gusher a hundred years later… - Lakeview Gusher - Northern RampartUpdated: 2009-10-27 @ 23:18:47 EDT
Visit the site of America's most spectacular oil gusher a hundred years later… - Lakeview Gusher - Center of the WellUpdated: 2009-10-27 @ 23:18:39 EDT
An iron pipe stand at the center of America's greatest gusher… - Lakeview Gusher - Oil-Soaked SandUpdated: 2009-10-27 @ 23:18:30 EDT
Accidental asphalt pavement from the Lakeview gusher… - Lakeview Gusher - Gusher Site and MonumentUpdated: 2009-10-27 @ 23:18:19 EDT
Monument at the site of America's most spectacular oil gusher… - Lakeview Gusher - Scene of the Lakeview Gusher…Updated: 2009-10-27 @ 23:18:08 EDT
Site of America's most spectacular oil gusher… - Lakeview Oil Gusher - The Gusher in ProgressUpdated: 2009-10-27 @ 23:17:56 EDT
Contemporary postcard showing America's most spectacular oil gusher in 1910… - Seismic Testimony from the KurskUpdated: 2009-10-27 @ 19:40:45 EDT
The death agony of the Russian submarine Kursk was heard by the world seismograph network… - Asteroid GeologyUpdated: 2009-10-15 @ 23:28:02 EDT
Recent work is finding remnants of planetary formation in the astroid belt… - What Is Geology's Nobel Prize?Updated: 2009-10-15 @ 23:13:59 EDT
Nothing in geology quite measures up to the Nobel Prize… - Earth Science Week - A Special Week for EarthUpdated: 2009-10-10 @ 00:35:09 EDT
Six months away from Earth Day is a whole week for Earth science: Earth Science Week… - Looking Deeply Into GlaciersUpdated: 2009-10-09 @ 23:56:36 EDT
Ways of examining glaciers close up, inside, and underneath… - [Updated: 2009-10-09 @ 08:01:13 EDT
: yardang kess kopje… - [Updated: 2009-10-08 @ 00:28:42 EDT
: whiz quiz silicate minerals geo quiz dimensional matrix tetrahedra… - Mineral Habits - Rosette HabitUpdated: 2009-10-01 @ 14:46:29 EDT
Barite commonly displays a rosette habit… - Mineral Habits - Rhombohedral HabitUpdated: 2009-10-01 @ 14:44:56 EDT
Calcite forms rhombohedral grains… - Mineral Habits - Reniform HabitUpdated: 2009-10-01 @ 14:43:37 EDT
Hematite shows the reniform habit… - Mineral Habits - Radiating HabitUpdated: 2009-10-01 @ 14:42:28 EDT
A pyrite dollar shows radiating habit… - Mineral Habits - Prismatic HabitUpdated: 2009-10-01 @ 14:37:33 EDT
Prismatic habit is usually shown by tourmaline… - Mineral Habits - Micaceous HabitUpdated: 2009-10-01 @ 14:33:18 EDT
Micaceous habit is exemplified here not by mica but by asbestos… - Mineral Habits - Massive HabitUpdated: 2009-10-01 @ 14:32:09 EDT
Quartz shows a massive habit in this gneiss… - Mineral Habits - Lamellar HabitUpdated: 2009-10-01 @ 14:26:42 EDT
Thick gypsum chunks show a lamellar habit… - Mineral Habits - Granular HabitUpdated: 2009-10-01 @ 14:24:50 EDT
The granular habit involves poorly formed crystals, unlike the equant habit… - Mineral Habits - Fibrous HabitUpdated: 2009-10-01 @ 14:22:22 EDT
Rutile takes a fibrous form in quartz… - Mineral Habits - Equant HabitUpdated: 2009-10-01 @ 14:20:03 EDT
The equant habit is more or less round… - Mineral Habits - Drusy HabitUpdated: 2009-10-01 @ 14:18:07 EDT
Drusy minerals form crystalline crusts… - Mineral Habits - Cruciform HabitUpdated: 2009-10-01 @ 14:14:20 EDT
Cruciform minerals commonly occur in crossed twins… - Mineral Habits - Botryoidal HabitUpdated: 2009-10-01 @ 14:12:14 EDT
Botryoidal mineral tend to look like grape clusters… - Mineral Habits - Blocky HabitUpdated: 2009-10-01 @ 14:10:37 EDT
Pyrite grains display a blocky habit… - Mineral Habits - Bladed HabitUpdated: 2009-10-01 @ 14:08:42 EDT
Kyanite exemplifies the bladed mineral habit… - Mineral Habits - Amygdaloidal HabitUpdated: 2009-10-01 @ 14:06:14 EDT
Amydaloidal minerals form in amygdules… - Mineral Streak - Identifying Cinnabar and Hematite by Streak…Updated: 2009-10-01 @ 14:01:37 EDT
Streak colors are distinctive for cinnabar and hematite… - Native Copper - Elemental Minerals - Pictures of Native Elements…Updated: 2009-10-01 @ 13:58:07 EDT
Copper, the element Cu, is found in nature in native form… - Mineral Streak - Identifying Native Metals by Streak…Updated: 2009-10-01 @ 13:56:50 EDT
Three native metals, gold, platinum and copper, identified by streak… - Mineral Streak - Beware of ScratchesUpdated: 2009-10-01 @ 13:54:25 EDT
Some minerals, like corundum, are harder than the streak plate… - Mineral Streak - The Typical White StreakUpdated: 2009-10-01 @ 13:53:15 EDT
Most minerals have a white streak… - Mineral Streak - White and Black Streak Plates…Updated: 2009-10-01 @ 13:52:29 EDT
Streak plates come in white and black… - Mineral Streak - Identifying Copper Sulfide Minerals by Streak…Updated: 2009-10-01 @ 13:51:57 EDT
Copper sulfide minerals have very similar streaks… - Mineral Streak - Identifying Magnetite by Streak…Updated: 2009-10-01 @ 13:50:41 EDT
Magnetite has a black streak… - Mineral Streak - Identifying Galena by Streak…Updated: 2009-10-01 @ 13:49:46 EDT
Galena's streak differentiates it from hematite… - Mineral Streak - Identifying Minerals by Streak…Updated: 2009-10-01 @ 13:46:58 EDT
About this simple but effective field technique for mineral identification… - About SandUpdated: 2009-09-29 @ 20:53:54 EDT
Sand-related sites are as numerous as sand grains… - Geology of the Sutter Buttes, California Updated: 2009-09-21 @ 00:52:58 EDT
Pictures, maps and notes from the Sutter Buttes of central California, 'the world's smallest mountain range.'… - Cross-Peen Crack Hammer - Rock HammersUpdated: 2009-09-20 @ 23:03:50 EDT
Cross-peen crack hammers are for hard-rock country… - Chisel, Mason's or Bricklayer's Hammer - Rock Hammers…Updated: 2009-09-20 @ 23:02:19 EDT
The chisel or bricklayer's hammer is for use in fossil hunting or examining stratified rocks… - Geologist's or Prospector's Hammer - Rock Hammers…Updated: 2009-09-20 @ 23:00:17 EDT
The prospector's hammer is the typical geologist hammer… - Gallery of Artificial Rocks - SlagUpdated: 2009-09-19 @ 20:06:40 EDT
Slag is a form of artificial rock… - Gallery of Artificial RocksUpdated: 2009-09-14 @ 17:03:19 EDT
Bricks, mortar, concrete, plaster and other artificial rocks… - What Is Geology?Updated: 2009-09-13 @ 21:01:25 EDT
The whole of Earth sciences, compressed to a nutshell… - Petroleum in a NutshellUpdated: 2009-09-11 @ 00:19:03 EDT
The basics about this important geologic commodity… - Where Were You for Loma Prieta?Updated: 2009-09-10 @ 20:57:37 EDT
Memories come rumbling back at this time of year, especially to your About Geology Guide… - Over the Coasts: An Aerial View of Geology by Michael CollierUpdated: 2009-09-09 @ 20:50:28 EDT
A book to make anyone dream like a geologist… - Carbonate Minerals - Calcite PictureUpdated: 2009-09-08 @ 00:23:15 EDT
Calcite is one of the carbonate minerals… - Carbonate Minerals Updated: 2009-09-08 @ 00:18:09 EDT
Two major minerals and a host of popular minor ones… - Carbonate Minerals - Siderite PictureUpdated: 2009-09-08 @ 00:17:10 EDT
Siderite is one of the carbonate minerals… - Redoubt Volcano, Alaska, USAUpdated: 2009-09-05 @ 00:26:17 EDT
Redoubt Volcano, one of Alaska's many volcanoes.: volcanic ash advisory centers aleutian volcanic arc redoubt volcano u s geological survey eruption plume… - Must Reads: Essential Articles and Resources about GeologyUpdated: 2009-09-03 @ 13:48:37 EDT
- The Tokai Earthquake of 20xxUpdated: 2009-09-03 @ 12:32:43 EDT
Japan has been preparing for it for over 25 years… - Contact the Geology GuideUpdated: 2009-09-01 @ 14:47:25 EDT
FAQ and directions for contacting About Geology Guide Andrew Alden… - Tourmaline Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:58:43 EDT
Tourmaline is one of the silicate minerals… - Talc Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:58:17 EDT
Talc is one of the silicate minerals… - Staurolite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:57:53 EDT
Staurolite is one of the silicate minerals… - Oxide Minerals - Spinel PictureUpdated: 2009-08-24 @ 20:57:22 EDT
Spinel is one of the oxide minerals… - Sillimanite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:56:51 EDT
Sillimanite is one of the silicate minerals… - Serpentine (Chrysotile) Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:55:48 EDT
Serpentine is one of the silicate minerals… - Scapolite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:55:18 EDT
Scapolite is one of the silicate minerals… - Oxide Minerals - Rutile PictureUpdated: 2009-08-24 @ 20:54:49 EDT
Rutile is one of the oxide minerals… - Quartz Picture Gallery - Quartz and Silica MineralsUpdated: 2009-08-24 @ 20:54:18 EDT
Get familiar with quartz… - Pyroxene Minerals - Pictures of the PyroxenesUpdated: 2009-08-24 @ 20:53:42 EDT
The pyroxene minerals are major parts of the crust and mantle… - Pyrophyllite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:50:53 EDT
Pyrophyllite is one of the silicate minerals… - Prehnite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:50:23 EDT
Prehnite is one of the silicate minerals… - Oxide Minerals - Magnetite PictureUpdated: 2009-08-24 @ 20:48:42 EDT
Magnetite is one of the oxide minerals… - Lazurite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:48:12 EDT
Lazurite is one of the silicate minerals… - Kyanite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:47:47 EDT
Kyanite is one of the silicate minerals… - Graphite or Native Carbon - Elemental Minerals - Pictures of Native …Updated: 2009-08-24 @ 20:47:19 EDT
Carbon, the element C, occurs in native form as graphite… - Garnet - Pictures of the Garnet MineralsUpdated: 2009-08-24 @ 20:46:47 EDT
Major members of the garnet group of minerals… - Rock-Forming Minerals - Feldspar PictureUpdated: 2009-08-24 @ 20:45:53 EDT
Feldspar is a major rock-forming mineral… - Epidote Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:45:21 EDT
Epidote is one of the silicate minerals… - Dumortierite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:44:51 EDT
Dumortierite is one of the silicate minerals… - Native Carbon or Diamond - Elemental Minerals - Pictures of Native E…Updated: 2009-08-24 @ 20:44:18 EDT
Diamond is a rare form of carbon, the element C, in native form… - Oxide Minerals - Corundum PictureUpdated: 2009-08-24 @ 20:43:50 EDT
Corundum is one of the oxide minerals… - Chlorite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:43:09 EDT
Chlorite is one of the silicate minerals… - Beryl Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:42:44 EDT
Beryl is one of the silicate minerals… - Benitoite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:42:05 EDT
Benitoite is one of the silicate minerals… - Axinite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:41:41 EDT
Axinite is one of the silicate minerals… - Carbonate Minerals - Aragonite PictureUpdated: 2009-08-24 @ 20:41:00 EDT
Aragonite is one of the carbonate minerals… - Andalusite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:40:26 EDT
Andalusite is one of the silicate minerals… - Amphibole MineralsUpdated: 2009-08-24 @ 20:39:53 EDT
Gallery of amphibole minerals… - Zircon Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:39:00 EDT
Xircon is one of the silicate minerals… - Topaz Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:37:59 EDT
Topaz is one of the silicate minerals… - Titanite (Sphene) Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:37:20 EDT
Titanite, or sphene, is one of the silicate minerals… - Sodalite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:36:02 EDT
Sodalite is one of the silicate minerals… - Olivine Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:34:01 EDT
Olivine is one of the silicate minerals… - Nepheline Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:33:34 EDT
Nepheline is one of the silicate minerals… - Muscovite Mica - Pictures of Mica MineralsUpdated: 2009-08-24 @ 20:33:01 EDT
Muscovite is an aluminum-rich member of the mica minerals… - Leucite Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:31:56 EDT
Leucite is one of the silicate minerals… - Amphibole Minerals - Hornblende PictureUpdated: 2009-08-24 @ 20:30:41 EDT
Hornblende in the gallery of amphibole minerals… - Eudialyte Picture - The Silicate MineralsUpdated: 2009-08-24 @ 20:29:36 EDT
Eudialyte is one of the silicate minerals… - Pyroxene Minerals - Enstatite PictureUpdated: 2009-08-24 @ 20:29:15 EDT
Enstatite is one of the pyroxene minerals… - Biotite Mica - Pictures of Mica MineralsUpdated: 2009-08-24 @ 20:28:48 EDT
Biotite is an iron-rich member of the mica minerals… - Pyroxene Minerals - Augite PictureUpdated: 2009-08-24 @ 20:28:10 EDT
Augite is one of the pyroxene minerals… - Phosphate Minerals - ApatiteUpdated: 2009-08-24 @ 20:27:52 EDT
Apatite is the principal phosphate mineral… - List of Official State Rocks by StateUpdated: 2009-08-22 @ 01:07:59 EDT
Twenty-five states honor 17 different rocks as state rocks or state stones… - Official State Rocks and State Stones of the United States - Coal - …Updated: 2009-08-22 @ 01:05:30 EDT
Coal is the state rock of Utah… - Native Sulfur - Elemental Minerals - Pictures of Native ElementsUpdated: 2009-08-21 @ 00:56:57 EDT
Sulfur, the element S, is found in nature in native form… - Sulfide Minerals - Sphalerite PictureUpdated: 2009-08-21 @ 00:55:45 EDT
Sphalerite is one of the sulfide minerals… - Native Silver - Elemental Minerals - Pictures of Native ElementsUpdated: 2009-08-21 @ 00:55:04 EDT
Silver, the element Ag, is sometimes found in nature in native form… - Carbonate Minerals - Rhodochrosite PictureUpdated: 2009-08-21 @ 00:53:09 EDT
Rhodochrosite is one of the carbonate minerals… - Sulfide Minerals - Pyrite PictureUpdated: 2009-08-21 @ 00:51:40 EDT
Pyrite is one of the sulfide minerals… - Native Platinum - Elemental Minerals - Pictures of Native ElementsUpdated: 2009-08-21 @ 00:50:51 EDT
Platinum, the element Pt, occurs in native form… - Sulfide Minerals - Molybdenite PictureUpdated: 2009-08-21 @ 00:50:04 EDT
Molybdenite is one of the sulfide minerals… - Sulfide Minerals - Marcasite PictureUpdated: 2009-08-21 @ 00:46:46 EDT
Marcasite is one of the sulfide minerals… - Carbonate Minerals - Magnesite PictureUpdated: 2009-08-21 @ 00:45:11 EDT
Magnesite is one of the carbonate minerals… - Native Gold - Elemental Minerals - Pictures of Native ElementsUpdated: 2009-08-21 @ 00:43:14 EDT
Gold, the element Au, is usually found in nature in native form… - Sulfide Minerals - Galena PictureUpdated: 2009-08-21 @ 00:42:36 EDT
Galena is one of the sulfide minerals… - Sulfide Minerals - Cinnabar PictureUpdated: 2009-08-21 @ 00:40:34 EDT
Cinnabar is one of the sulfide minerals… - Sulfide Minerals - Chalcopyrite PictureUpdated: 2009-08-21 @ 00:40:09 EDT
Chalcopyrite is one of the sulfide minerals… - Oxide Minerals - CassiteriteUpdated: 2009-08-21 @ 00:39:41 EDT
Cassiterite is one of the oxide minerals… - Sulfide Minerals - Bornite PictureUpdated: 2009-08-21 @ 00:38:18 EDT
Bornite is one of the sulfide minerals… - Evaporite Minerals and Halides - UlexiteUpdated: 2009-08-20 @ 23:55:59 EDT
Ulexite is one of the evaporite minerals… - Mineral Picture GalleryUpdated: 2009-08-20 @ 23:55:31 EDT
The mineral wing of the About Geology Picture Gallery… - Evaporite Minerals and Halides - Sylvite PictureUpdated: 2009-08-20 @ 23:54:57 EDT
Sylvite is one of the halide minerals… - Evaporite Minerals and Halides - Halite PictureUpdated: 2009-08-20 @ 23:52:04 EDT
Halite is one of the halide minerals… - Sulfate Minerals - Gypsum Rose PictureUpdated: 2009-08-20 @ 23:50:59 EDT
Gypsum is one of the sulfate minerals… - Evaporite Minerals and Halides - Borax PictureUpdated: 2009-08-20 @ 23:50:19 EDT
Borax is one of the evaporite minerals… - Sulfate Minerals - Anhydrite PictureUpdated: 2009-08-20 @ 23:49:39 EDT
Anhydrite is one of the sulfate minerals… - Carbonate Minerals - Witherite PictureUpdated: 2009-08-20 @ 23:48:52 EDT
Witherite is one of the carbonate minerals… - Willemite Picture - The Silicate MineralsUpdated: 2009-08-20 @ 23:48:21 EDT
Willemite is one of the silicate minerals… - Phosphate Minerals - VarisciteUpdated: 2009-08-20 @ 23:47:50 EDT
Variscite is a colorful phosphate mineral common in rock shops… - Phosphate Minerals - TurquoiseUpdated: 2009-08-20 @ 23:47:16 EDT
Turquoise, a precious gemstone, is also a phosphate mineral… - Carbonate Minerals - Smithsonite PictureUpdated: 2009-08-20 @ 23:45:50 EDT
Smithsonite is one of the carbonate minerals… - Phosphate Minerals - PyromorphiteUpdated: 2009-08-20 @ 23:45:05 EDT
Pyromorphite is a significant phosphate mineral and ore of lead… - Oxide Minerals - Pyrolusite PictureUpdated: 2009-08-20 @ 23:44:32 EDT
Pyrolusite is one of the oxide minerals… - Oxide Minerals - Psilomelane PictureUpdated: 2009-08-20 @ 23:43:19 EDT
Psilomelane is one of the oxide minerals… - Quartz and Silica Minerals Gallery - Opal PictureUpdated: 2009-08-20 @ 23:42:18 EDT
Opal is a hydrated form of amorphous silica… - Carbonate Minerals - Malachite PictureUpdated: 2009-08-20 @ 23:41:29 EDT
Malachite is one of the carbonate minerals… - Hemomorphite Picture - The Silicate MineralsUpdated: 2009-08-20 @ 23:41:00 EDT
Hemimorphite is one of the silicate minerals… - Oxide Minerals - Hematite PictureUpdated: 2009-08-20 @ 23:40:13 EDT
Hematite is one of the oxide minerals… - Evaporite Minerals and Halides - FluoriteUpdated: 2009-08-20 @ 23:39:41 EDT
Fluorite is one of the halide minerals… - Carbonate Minerals - Dolomite PictureUpdated: 2009-08-20 @ 23:35:59 EDT
Dolomite is one of the carbonate minerals… - Dioptase Picture - The Silicate MineralsUpdated: 2009-08-20 @ 23:35:22 EDT
Dioptase is one of the silicate minerals… - Oxide Minerals - Cuprite PictureUpdated: 2009-08-20 @ 23:34:22 EDT
Cuprite is one of the oxide minerals… - Chrysocolla Picture - The Silicate MineralsUpdated: 2009-08-20 @ 23:32:02 EDT
Chrysocolla is one of the silicate minerals… - Quartz and Silica Minerals Gallery - Cryptocrystalline Quartz in Che…Updated: 2009-08-20 @ 23:31:28 EDT
A fractured chert pebble displays silica in its cryptocrystalline form… - Carbonate Minerals - Cerussite PictureUpdated: 2009-08-20 @ 23:30:55 EDT
Cerussite is one of the carbonate minerals… - Sulfate Minerals - Celestine or Celestite PictureUpdated: 2009-08-20 @ 23:30:19 EDT
Celsetine or celestite is one of the sulfate minerals… - Sulfate Minerals - Barite Roses PictureUpdated: 2009-08-20 @ 23:28:47 EDT
Barite is one of the sulfate minerals… - Pyroxene Minerals - Rhodonite PictureUpdated: 2009-08-20 @ 00:49:42 EDT
Rhodonite is one of the pyroxenoid minerals… - Geology of San Francisco, California - Basalt in the Japanese Tea Ga…Updated: 2009-08-19 @ 00:33:23 EDT
The stones of the Japanese Tea Garden make it one of San Francisco's geologic attractions… - Slate - All About SlateUpdated: 2009-08-18 @ 15:35:30 EDT
Slate is a widely used low-grade metamorphic rock… - Retrograde MetamorphismUpdated: 2009-08-16 @ 15:09:00 EDT
A schist has nodules where garnets once were.: queen canyon pressure rocks mica schist rare diamonds… - Potassium-Argon Dating Methods - K-Ar and Ar-Ar DatingUpdated: 2009-08-15 @ 18:11:04 EDT
Potassium-argon isotopic dating is especially useful for determining the age of lavas… - Fault Map of Parkfield Segment - San Andreas Fault at ParkfieldUpdated: 2009-08-15 @ 01:09:39 EDT
Map showing faults and topography of the Parkfield segment of the San Andreas fault… - SAFOD Drilling Rig - San Andreas Fault at ParkfieldUpdated: 2009-08-15 @ 01:09:03 EDT
The drilling rig of the San Andreas Fault Observatory at Depth (SAFOD) project north of Parkfield… - SAFOD Drilling Profile - San Andreas Fault at ParkfieldUpdated: 2009-08-15 @ 01:08:49 EDT
Schematic profile and geologic section of the SAFOD drill hole across the San Andreas fault… - Drill Cuttings at SAFOD - San Andreas Fault at ParkfieldUpdated: 2009-08-15 @ 01:08:34 EDT
Grit from the borehole bottom is collected by the SAFOD project to study the San Andreas fault… - Adjust the Crown-O-Matic - San Andreas Fault at ParkfieldUpdated: 2009-08-15 @ 01:08:10 EDT
Warning sign on drilling equipment reinforces safety at the SAFOD drilling project to study the San Andreas fault… - Parkfield Ground Squirrel - San Andreas Fault at ParkfieldUpdated: 2009-08-15 @ 01:07:53 EDT
Local wildlife patronizes the offerings at the SAFOD drill site near Parkfield, California… - SAFOD in the News - San Andreas Fault at ParkfieldUpdated: 2009-08-15 @ 01:07:38 EDT
Mark Zoback is interviewed for television, informing the public about geology research… - The 28 September Parkfield Earthquake - San Andreas Fault at Parkfie…Updated: 2009-08-15 @ 01:07:18 EDT
The first hour of postseismic activity after the 28 September 2004 Parkfield earthquake… - Cholame Valley - San Andreas Fault at ParkfieldUpdated: 2009-08-15 @ 01:06:52 EDT
Cholame Valley in the Parkfield segment of the San Andreas fault… - Parkfield Cafe - San Andreas Fault at ParkfieldUpdated: 2009-08-15 @ 01:01:39 EDT
The Parkfield Cafe is famous for its hospitality among geologists studying the San Andreas fault… - The Fitness of GeologyUpdated: 2009-08-13 @ 18:22:25 EDT
Geologists may be the fittest of scientists… - Sherlock Holmes, Forensic GeologistUpdated: 2009-08-13 @ 16:54:22 EDT
The great detective Sherlock Holmes is the exemplar of the modern geologist… - Igneous Rock Types - Pictures of Igneous Rocks…Updated: 2009-06-10 @ 13:55:52 EDT
The major igneous rock types, plutonic, intrusive and extrusive… - Geology of San Francisco, CaliforniaUpdated: 2009-05-21 @ 23:00:12 EDT
A photo tour of San Francisco's geologic attractions… - Mineral HabitsUpdated: 2009-05-20 @ 00:57:27 EDT
The various forms that minerals take in rocks… - The Silicate MineralsUpdated: 2009-05-03 @ 09:25:56 EDT
The great majority of rocks are made of silicate minerals… - Oxide MineralsUpdated: 2009-04-24 @ 17:40:53 EDT
A varied mineral group with simple formulas… - Sulfide MineralsUpdated: 2009-04-22 @ 20:32:38 EDT
is one of the sulfide minerals… - Evaporite Minerals and HalidesUpdated: 2009-04-21 @ 20:47:13 EDT
Introducing the halides and evaporite minerals… - Sulfate MineralsUpdated: 2009-04-17 @ 19:54:59 EDT
Sulfate minerals form near the Earth's surface… - Phosphate MineralsUpdated: 2009-04-16 @ 00:59:19 EDT
Minerals that include this important element… - Mica Minerals - Pictures of MicasUpdated: 2009-04-14 @ 19:05:36 EDT
The micas include several notable mineral species… - Elemental Minerals - Pictures of Native Elements…Updated: 2009-04-13 @ 20:43:08 EDT
Notable elements that are found in nature in native form… - Rock-Forming MineralsUpdated: 2009-04-03 @ 17:50:45 EDT
A handful of very abundant minerals account for the great majority of the Earth's rocks… - Official State Rocks and State Stones of the United StatesUpdated: 2009-01-14 @ 19:57:22 EST
Twenty-five states have honored 17 different state rocks or state stones. Here they are… - Washington DC Geology Updated: 2008-11-21 @ 11:47:16 EST
Pictures showing geology in Washington, DC… - San Andreas Fault at Parkfield - Pictures of the San Andreas FaultUpdated: 2008-11-14 @ 19:01:18 EST
Photos and notes from the San Andreas fault segment centered on Parkfield, California… - Rock Hammers - Pick the Right HammerUpdated: 2008-06-19 @ 17:10:17 EDT
Hammers that geologists and rockhounds use… - Lakeview Oil Gusher - Greatest Oil Gusher of Them All…Updated: 2007-03-22 @ 20:12:45 EDT
Visit the site of America's most spectacular oil gusher a hundred years later…