It seems that by far the most popular part of the Geology Forum is people asking for help identifying their rocks, and the most popular of those, in turn, seem ... Read More

Every Monday morning at 1 o'clock, my weekly email newsletter goes out to thousands of subscribers. What's it like, you may wonder, and is it worth subscribing to given all ... Read More

UNESCO's World Heritage Committee has named some new localities to the list of sites, one of which is dear to geologists: the Dolomite range in northern Italy. The announcement noted ... Read More

A common landform in deserts is the inselberg, a remnant rock standing alone after all around it has eroded away. You pronounce it like a German would, "INN-sel-BAIRG," which means ... Read More

It was a big day for science Tuesday as the Sanford Underground Laboratory was formally dedicated in the former Homestake Mine in the Black Hills of South Dakota. The Rapid ... Read More

Once a band of gold prospectors discovered a peculiar area of spiky limestone protuberances high above the Stanislaus River. Between those spikes lay fist-sized gold nuggets, and soon an army ... Read More

Usually I try to help you understand the big picture, but every now and then a big photo is just the thing. This is Sarychev volcano, in the Kuril Islands ... Read More

We think we understand why Earth has a magnetic field: the liquid iron in the core acts as a gigantic dynamo. One of the first discoveries in geophysics is that ... Read More

As promised, I'm adding to the new picture gallery of erosional landforms. Today we have the valley and the hanging valley. "Valley" is a very general term in geology, so ... Read More

Many, perhaps the majority, of people's favorite landforms are formed by erosion. We seem to prefer the Grand Canyon to the Grand Bajada (if there even is one). In fact, ... Read More

Some beautiful building stones are extremely old. In Washington, DC, a showcase of decorative stone, the FDR monument is mostly Carnelian granite, of Proterozoic age (around 2600 million years). It's ... Read More

The area around Cleburne, Texas, just south of Fort Worth, has had a flurry of small earthquakes this year, including two last week. None of them has exceeded magnitude 3. ... Read More

Japan started a remarkable program in 1978 based on the certain knowledge that the Tokyo region has suffered great earthquakes, greater than magnitude 8, roughly every century—and that the last ... Read More

I'm thinking about my upcoming field trip to the Sierra foothills this weekend. The itinerary includes gold mines and mariposite localities, but the area is also known for andalusite, in ... Read More

Dunite is a deep-seated, heavy rock that consists almost entirely of the mineral olivine. Big bodies of dunite are quite rare. Your basic rock-shop specimens are usually dunite xenoliths, little ... Read More

Last weekend I visited my local volcanic park (every city should have one) and found myself transfixed by these little blobby things: amygdules. They started out as vesicles—gas bubbles—in the ... Read More

Having upgraded the rocks and minerals, it's time to move on to my photo-encyclopedia of landforms. The first stage, Depositional Landforms, is ready. These are mostly things made of sand ... Read More

Be careful what you read, because this slipped by some writers: a recent paper in Science made an excellent scientific case linking a huge, sustained volcanic outburst to a mass ... Read More

The beauty of the Web is that many journals give away part of their content. Such is the case with Science News, where ace geoscience reporter Sid Perkins surveys recent ... Read More

It was an abandoned oil-shale pit near the German city of Messel: the Grube Messel. But when they weren't digging up the black, flaky rock to be burned in furnaces, ... Read More

The two Americans who were listed as passengers on Air France flight 447 are geologist Michael Harris and his wife Anne, according to the Associated Press. He worked for Devon ... Read More

Carrying out remote meetings over the Web has a long history—in Web years. An early attempt at a 1998 GSA meeting linked two live audiences in Canada and Australia and ... Read More

An article in the May 19 Eos underscores why volcano monitoring, ridiculed by Bobby Jindal a few months ago, needs steady support. It's a report by 10 Alaska Volcanic Observatory ... Read More