This striking rock is none other than obsidian, which forms when lava cools rapidly with high silica content. This results in no crystals forming, giving obsidian its characteristic glassy appearance.
#TectonicTuesday #LapworthRocks #Obsidian #Volcanic #Volcano #Tectonic #Igneous #Geology #Museum
Where do volcanic bombs get their shape from? They become rounded due to cooling and solidifying mid-air after they are ejected from the volcano during an eruption.
Image by Greg Milner.
#LapworthRocks #TectonicTuesday #volcano #volcanic #tectonic #rocks #rock #geology #museum
What can we learn about the composition of our Earth? What are tectonic plates? Find out in our learning sessions, available for primary and secondary schools: ow.ly/UPi350WBbc3
#TectonicTuesday #LapworthRocks #learning #schools #geology
Fun fact: The Earth's tectonic plates move about as fast as your fingernails grow!
Another fact: Ben Miller once told jokes next to a lava lake!
Now he’s bringing his stand-up show Volcano to Birmingham on Fri 12 Sept. Join us for a lively night out!
lapworth-comedy.even...
#TectonicTuesday
Basalt is one of the most well-known and common igneous rocks. Did you know that basalt comprises more than 90% of volcanic rocks on Earth?
#LapworthRocks #TectonicTuesday #rocks #rock #igneous #tectonic #volcanic #volcano #basalt #museum #geology
This lantern slide shows a photograph by Tempest Anderson! Can you guess which active Italian #volcano is captured here? It famously erupted in 79 AD, burying nearby towns such as Pompeii and Herculaneum with #ash and #pyroclastic flows.
#TectonicTuesday #LapworthRocks #igneous #geology #museum
This breadcrust bomb comes from Mount St Helens, U.S, and forms in the same way a #volcanic bomb does, but gets its name from the characteristic cracked surface! This results from the outer surface cooling down and then cracking when gas bubbles expand from its hot interior.
#TectonicTuesday
Lapworth's Lava Chicken, yeah, it's tasty as hell! 🎶
#TectonicTuesday #LapworthRocks #geologyrocks #geology #igneous #metamorphic #volcano #tectonic #bird #museum #Minecraft #MinecraftMovie
Rhyolite is an extrusive #igneous rock formed when a silica-rich #magma is pushed out of a #volcanic vent and quickly cools on the planet's surface!
Explore this model at https://skfb.ly/ov7UF
#TectonicTuesday #LapworthRocks #geologyrocks #geology #metamorphic #volcano #tectonic #museum
A folded amphibolite being held up in front of a wall of 13 other rocks. The amphibolite is grey with darker grey bands in it. The bands are folded in an undulating way. The rock wall behind is brown in colour and there is an array of rocks displayed. Some are folded and others are fractured.
Did you know that, under the right conditions, rocks can bend?
For today’s #TectonicTuesday, here are some folds in banded amphibolite found in Norway.
Studying the geometry of folds can help us understand the deformation history of rocks.
#TectonicTuesday #SedgwickMuseum #EarthSciences
Tiny rootless fold in dolomite. Picture is of a hand sample. Rock is grey to earthy in color. It is an accentuated streaky appearance. Deformation in the footwall of Munisiyari Thrust which places Paleoproterozoic gneiss over Neoproterozoic Lesser Himalaya. Location. Munsiyari town baazaar road towards petrol pump, Uttarakhand, India.
Outcrop view of pale yellow dolomite showing rootless folds. Rock is from the footwall of Munsiyari Thrust, which places Paleoproterozoic gneiss over Neoproterozoic Lesser Himalaya. Location. Munsiyari bazaar road to petrol pump. Uttarakhand, India.
Rootless folds in footwall dolomite of the Munsiyari thrust.
This thrust places Paleoproterozoic gneiss over Neoproterozoic metasedimentary Lesser Himalaya. Considered to be the floor thrust of the Main Central Thrust zone.
Loc: Road from Munisiyari baazar to petrol pump.
#TectonicTuesday
A museum staff member holding the rock up in front of a wall of 13 other rocks. The specific specimen is a deep/purple colour with fine layers of red/orange colour too. The layers are displaced.
A close up of the rock where you can see the layers in more detail. They are extremely fine , hence the term 'laminated' is used.
What’s the story behind this fascinating rock?
It is laminated layers of shales and jaspers found in North West Queensland, Australia, formed 500 million years ago. These colourful layers do not align because they have been faulted (fractured and displaced).
#TectonicTuesday #Faulting #Geology
A wall of thirteen rocks showing various different types of deformation. You can see folding, bending and fracturing.
Ever wondered what happens to rocks under pressure? 🪨
Deformation is the change rocks undergo when force (known as stress) is applied to them. Factors like the rate of stress, temperature, and pressure influence the type of deformation that occurs.
#TectonicTuesday #RockDeformation #Geology
View of regional northerly dips of Greater Himalaya Sequence from Khati village, entrance to Sunderdunga and Pindari valley, Kumaon.
View of regional northerly dips of Greater Himalaya Sequence from Baaling village, Darma Valley, Kumaon.
View of regional northerly dips of Greater Himalaya Sequence, from near Bawaldhar, entrance to Johar valley and Milam Glacier. Kumaon.
A close up of thinly bedded northerly dipping high grade metamorphic rocks of the Greater Himalaya Sequence in Sunderdunga valley, Kumaon.
The Greater Himalaya is a northerly dipping homoclinal medium to high grade metamorphic slab.
Examples from the Kumaon Himalaya.
#TectonicTuesday
Attenuation of the limbs in these folds has left some of the fold hinges essentially floating.
#Laxfordian folding on the north west coast of the #IsleofLewis
#TectonicTuesday #Geology #Lewisian #Folding ⚒️🧪
