Geobulletin alpha

Educator How-to: Learn to Draw a Celtic Triquetra 

At the Houston Museum of Natural Science, we know that people are as much a part of natural science as rocks and dinosaurs. That’s why we love social studies and maintain exhibits like the John P. McGovern Hall of the … Continue reading

Sculpture in Stone 

Geologist and science writer Nina Morgan* visits the bi-annual OnForm sculpture show in Oxfordshire – the only UK exhibition dedicated exclusively to stone sculpture… It’s generally a lot easier to examine the lithological characteristics of rocks away from their natural setting in the field. The bi-annual OnForm sculpture show, a spectacular exhibition of contemporary stone … Continue reading

What evidence do living organisms leave behind in rocks? 

'Trace fossils - burrows or borings' Living creatures often leave behind evidence of their activity in rocks, even if their actual remains are not found as body fossils. Clues may be obtained from living examples, which we can study in their modern habitats. In this activity, pupils are invited to apply previously learned observations about the features of modern bivalve shells to the

Friday fold: Mesoscopic structures in the Lightning Creek Schist 

There are some structural goodies here at the confluence of the Rapid River and the Salmon River in west-central Idaho. I visited these outcrops three weeks ago on a field trip after the Rocky Mountain section meeting of GSA. The rocks are the Lightning Creek Schist, a schist that’s part of the Wallowa Terrane, an accreted chunk of crust that docked with western North America during the Mesozoic. Here is

Rock Explorers for young children 

The new ELI today is part of our series ELI Early years, 'Rock Explorers; putting rocks into families'. As Rock Explorers, pupils investigate a variety of rocks and sort them into groups. The activity includes opportunities for literacy, numeracy and art. You could ask the pupils how they think the rocks might be used, e.g. the White family might be used to decorate buildings, the Pink

Peilinia quadriplicata pelecypod from Texas 

Another pretty cool looking oyster that I found in the Texas creek I was exploring is Peilinia quadriplicata (also called Ostrea quadriplicata). This species is very easy to ID based on the look of the shell. I only found a left valve but it has the typical splayed look to it, kind of like a duck foot. While the shell started out with a relatively smooth margin, as the animal grew older it started to have some distinct "points" with flat, straight areas of margin between them. Overall the shell [...]

Field Work on Black Mountain 

San Diego, CA – Amineh AlBashaireh (’18) and I are working with USD scientists, Dr. Bethany O’Shea, Elizabeth Johnston, and Eric Cathcart on the geology of Black Mountain in San Diego, CA. The Santiago Peak Volcanics are exposed in the park. These rocks are early Cretaceous in age (~110 Ma) and are thought to represent the

Where my rocks go to die 

For many years I saved and collected rocks. This was especially true during my years at About.com, when I put together a large set of photos and explanations to help people learn about rocks. When About.com dropped my contract in 2014, I’d reached “peak rocks.” My office had rocks everywhere, and my closet had still

Hindia sphaeroidalis sponge from the Viola formation of Oklahoma 

I found one specimen of the sponge fossil called Hindia sphaeroidalis. in the Viola formation roadcut south of Sulphur, OK. This species spans many millions of years and is known in rocks from the Ordovician up through the lower Devonian. I've also found examples of this species from the lower Devonian aged Kalkberg formation of New York, but there they seemed to get much larger. The shape of the fossil is like a large pea with many small openings on all surfaces. The round shape seems to [...]

Lichenalia torta? bryozoan from the Moscow formation of New York 

Within the rocks of Fall Brook, near Geneseo, NY, sometimes you'll find odd dark colored fossils that look as though someone poured chocolate on the rock. I knew it was a fossil of some kind but getting a piece to reveal itself face up was not an easy task. So I kept a few pieces in the hopes that one day I would figure out what it could be. Now I may have an answer. While I was looking through the plates within the Paleontology of New York, volume  VI, I came across an illustration that [...]

April 23rd - Sully Island and Lavernock Point and copy of talk on Chernobyl, April 7th 

Saturday 23rd AprilSully Island and Lavernock PointLeader: Professor Maurice Tucker, University of Bristol and Bath Geological SocietyThe Triassic rocks near Sully and Penarth (50 miles west of Bristol), near Cardiff, were deposited around the edge of a lake or inland sea in which the Mercia Mudstone/ Keuper Marl was deposited. The Trias overlies the Carboniferous limestone which locally created hills and cliffs around the lake; wave-cut shore-platforms and wave-notches were cut into the [...]

Questions to ask at any rock face about tilted and folded rocks 

Our fieldwork series continues with 'Questions for any rock face 7: tilted or folded rocks; what questions about tilting and folding might be asked at any rock exposure?' Bedded sediments that were originally laid down horizontally, often became tilted as part of the limbs of larger folds; sometimes the folds themselves can be seen in the rock face. Take the pupils to some tilted or

A terrifying video of two coaches trapped by “shooting rocks” in Pakistan 

A terrifying video has appeared on Youtube showing two buses trapped by "shooting rocks" on the Karakorum Highway in

‘Popping Rocks’ with Robots 

It turns out that studying lava flows at the bottom of the ocean uses many of the same methods as studying lava flows on other planets, writes Lamont's Elise

Vallis Vale de la Beche unconformity - damage to this SSSI 

Message from Alan Holiday, DIGS Group "I was at Vallis Vale today with a group from Sherborne U3A. As you can see from the photo someone had had a bonfire on the unconformity surface!I wasn’t in a position to clear up the mess unfortunately.I was wondering if we might approach this through local school(s) if there is a geology dept or through geography or science  departments and try and get the staff on board to explain why this shouldn’t happen. When I was on the site in the summer [...]

Actinopteria sp. pelecypods from the Bois d'Arc formation 

I found a few pelecypod mold and casts during my hunt among the rocks of the Bois d'Arc formation in Oklahoma. All are without shell material and some have little detail with which to help identify them. One group of specimens does have some detail and appears to belong to the genus Actinopteria and may be A. textilis. The fossils I found are all of single valves but show impressions of the interior or exterior of the left or right valves. The shells have an overall rectangular outline with a [...]

New ELI - Questions to ask about fossils when looking at rocks 

The new ELI just published is 'Questions to ask at any rock face 6: fossils. What questions about fossils might be asked at any rock exposure?' - What happened to these animals/plants just after they died?- Were they buried where they were or moved around, sorted out and broken up?- As they were being buried, what might they have looked like, smelled like?- After they were buried, how did

4-5th and 18-19th June - Field Geology in Pembrokeshire (Part 2) 

Lifelong Learning 4 day course Field Geology in Pembrokeshire (Part  2)  Two weekends in June: 4th, 5th, 18th, 19th10.00 am – 5.00 pm each day. The Pembrokeshire landscape differs from much of Wales in that it is largely unmountainous, with extensive areas forming plateaux lying below 183m (600 ft). This course will visit a number of key coastal locations in the south of the county, examining rocks formed during Silurian, Devonian and Carboniferous times. The course is divided [...]

3D Impossipuzzles 

In its own way, Yorkshire culture is as crazy as Japanese culture. Today's cultural exercise was doing an impossible 3 dimensional puzzle halfway up a mountain (Ingleborough), in the rain. It was also quite cold (the ground was hard with ice as we set off up the hill) although it did warm to a few degrees above freezing later on. The game starts with a drystone wall. This is a wall of

Monday Geology Picture: Rocks on a Shelf 

Like many geologists, I like to decorate with rocks. This week’s “Monday Geology Picture” features some rocks on a shelf in my living room. There’s many more rocks on this shelf — this picture just shows a few of them. What do you spot in this picture? Among other things, I see an orthoceras fossil, some volcanic pumice, a botryoidal carbonate rock, a rock with a vein of gabbro, sandstone concretions,