Sunday, 29 December 2013

Antarctic Diamonds

Scientists have found evidence for diamonds in the icy mountains of Antarctica, however it is currently forbidden to recover minerals from the Antarctic for commercial purposes. Diamonds form from carbon that has been put under extreme heat and pressure, reaching up to 150km beneath the Earth's crust. Volcanic eruptions help to bring valuable crystals, including diamonds, to the Earth's surface, in blue rocks called kimberlites. These kimberlites have now been found in Antarctica in three separate samples, and are a specific type that suggests the presence of diamonds, however only 10% would be economically viable. The Protocol on Environmental Protection to the Antarctic Treaty has banned the extraction of mineral resources, except for scientific purposes, but this is up for review in 2041. At this time, views on mining here could change, and technology may have continued to advance, making it more economically viable to extract minerals here.
The paper that has been published regarding these kimberlites explains that they are 120 million years old, corresponding to the ages of other Cretaceous Gondwanan kimberlites from around the world. They have been brought up to the surface of the Earth due to the reactivation of a Graben (a trench that is bordered by normal faults) associated with rifting of India from Australia and Antarctica.

A Graben surrounded by normal faults

Tuesday, 24 December 2013

Fleshy Head

Mummified Edmontosaurus regalis (a herbivorous duck-billed dinosaur that is a member of the hadrosaurid family that lived between 75 and 65 million years ago) remains have been found in Alberta, Canada, with it's fleshy head ornament completely preserved. This is the first evidence of a dinosaur having a completely soft tissue crest - up to now, only bony crests have been preserved, as skin rarely fossilises. When the dinosaur died, it would have been buried instantly in sediments, where there would have been a lack of oxygen, slowing down the process of decay and allowing soft tissue to be mineralised.
The paper published in Current Biology (which unfortunately I can't get full access to without paying $30!) explains that the fleshy head ornament would have replaced the bony crests in hadrosaurids at the end of the Cretaceous (around 66 million years ago). It would have been used in a visual display to attract mates or to determine leadership in a herd.

A reconstruction of the fleshy head (courtesy of the BBC)
Other dinosaurs have been previously found with some soft tissue preservation. An article in Nature explains how a 113 million year old Scipionyx samniticus (a therapod dinosaur) fossil has been found with soft tissue preservation, whilst National Geographic explains about how a 70 million year old Tyrannosaurus rex fossil has also been found with some soft tissue from the thighbone.

Saturday, 21 December 2013

3D Specs at the Ready!

Today I received my winter copy of the Planet Earth magazine, which is in association with NERC (Natural Environment Research Council), and after flicking through it, one story in particular caught my eye. Researchers from the BGS (British Geological Society) are working on making the first ever 3D virtual fossil collection, by scanning the UK's finest fossils. So far they've taken thousand of high-resolution photos, 3D models and stereoscopic images of the fossils, and more information is being added all the time. Along with the photos are comprehensive fact sheets, explaining things such as where the fossils were found, what species they are and where they are stored. The photo files can be downloaded and they work with 3D printers (see my previous post about 3D printing), allowing for the possibility of perfect replicas to be used in classrooms for teaching purposes, without risk of damaging the fossils. I'd definitely recommend having a look at the 3D fossil collection, as you get to see the detail of fossils that you wouldn't normally get a chance to look at.

One of many 3D movable images (courtesy of  GB3D)

Thursday, 19 December 2013

Bremen Core Repository

For one of my modules with Uni, we had a trip to the Bremen Core Repository in the University of Bremen, Germany. Here we got to see how the 154km of cores are stored, in a 4 degrees centigrade room, in hundreds of movable rails.

Lots of Cores
More Cores!

Core Labels
We also got to see a drill rig that will soon be going back out to sea to drill for more cores, a close up of a drill bit, an XRF (X-Ray Fluorescence) machine, which is used for completely geochemical analysis on cores, and an MSCL (Multi-Sensor Core Logger) machine, which is used for high resolution imaging of cores.

Drill Rig

Drill Bit

XRF Machine

MSCL Machine
Then we went into a lab to start analysing the cores. First we put around 16 cores out onto special holders with rulers on, which make it easier for making accurate observations.

These cores are split into separate pieces where they have broken off, and these pieces can be split into sub-pieces. The sub-pieces have labels and arrows attached to them, to ensure that they are put back in the same place after analysis.

Core Pieces

Labels on Cores
An interesting core was from the KT (Cretaceous-Palaeogene) boundary, which occurred 66 million years ago. The boundary is clear to see, and is best known to mark the time of the dinosaur mass extinction event.

KT Boundary
Another interesting core shows how they are separated into a working half and an archive half. Samples cannot be taken from the archive half, but it can be used for surface analysis. The working half is where samples are taken from, and can include slices, thin sections and drills. Polystyrene is then put in place where the samples were taken from to mark when they originated.

Working and Archive Halves

We then started working on these cores, looking at their mineralogy, textures, structures and metamorphic features, to determine what rock they are. I was concentrating on the metamorphic features, looking for evidence of deformation. This can include reaction rims (which are areas between two minerals that are the products of reactions) and zonations (which is when a mineral changes composition as it grows).

Reaction Rim
This was a very interesting trip as we got to learn about cores in a working environment, as we saw how they are stored and how they are examined. We also got to look around Germany, and we went to the Christmas Market each evening, which was lovely. I'll end on a few snaps from the market - not geology related, but it shows that geology isn't all work and no play!

Market Stalls and a Soldier!



Market Stalls

Pretty Sunrise


More Rides!

Hauptbanhof (Main Station)

Saturday, 14 December 2013


The BBC has written a report about the supervolcano under the Yellowstone National Park, explaining that it is 2.5 times bigger than previously thought. It stretches for 55 miles and could contain up to 600 cubic km of molten rock, meaning that if an eruption occurred today, the consequences could be catastrophic. Yellowstone has had three major eruptions so far; 2.1 million years ago, 1.3 million years ago and 640,000 years ago, suggesting an average frequency of one every 700,000 years. This is a very rough estimate, as it is only based on two gaps between the three eruptions.
National Geographic explains that the most recent eruption was 1,000 times the size of the Mt St Helens eruption in 1980, with a pillar of ash rising 100,000 feet. Pyroclastic flows (dense fogs of ash, rocks and gas with a temperature of 800 degrees celsius) rolled along the landscape, welding itself to the ground. The eruption 2.1 million years ago was twice as strong, and the one 1.3 million years ago was slightly smaller, but still as devastating.
The Examiner goes on to explain that no supervolcano has erupted in human history, so it is hard to predict what will happen. They also say that there is an imminent danger, and that the magma is "ready to erupt", causing an eruption that would be 2,000 times larger than the Mt St Helens eruption in 1980.
However, the Yellowstone National Park Service believes that there is no evidence of an imminent catastrophic eruption, as geological activity has remained constant throughout the 30 years that it has been monitored. Instead the eruption is expected to occur in the next 1,000-10,000 years. This eruption could be in the form of a lava flow, oozing slowly for months and years, allowing people to have plenty of time to escape. Scientists also believe that they would examine the precursors to a catastrophic eruption for months or even years. These precursors include smaller volcanic eruptions, strong earthquake storms and ground deformation. The intensity of the precursors would increase closer to the time of the catastrophic eruption.
National Geographic gives a detailed explanation of what to expect from from a supervolcano. First, a hot plume would upwell, melting the rocks beneath the Earth's crust, forming a chamber filled with magma, rock, water vapour, carbon dioxide and other gases. The land would begin to dome upward as this material accumulates over thousands of years forming several fractures. The pressure in the chamber would build up, before being released through the fractures. The surface of the dome would collapse, leaving behind a caldera.
So it seems there is some controversy over the timescale in which Yellowstone will erupt, and the severity of the eruption, but hopefully us geologists will be able to keep an eye on things to give people enough warning about the impending doom!

Wednesday, 11 December 2013

Hot Stuff!

Nasa's Iris mission has been observing the Sun's surface and its outer layers, where the temperatures can reach up to 2,000,000 degrees centigrade, with explosions of plasma moving at hundreds of kilometres per hour. This mission has been designed to help get a better understanding of space weather, as solar storms and flares have the potential to disrupt power supplies, transport and communications systems here on Earth.

Image of a Solar Storm (Courtesy of The BBC)
Earth Magazine goes into solar activity in more detail, looking into its possible effects and the vulnerability of power grids and satellites. If a massive solar storm hit the Earth, the impacts could be the worst that mankind has ever faced. If power was lost for a few months or years, commerce would stop immediately, with only a few shops remaining open using cash. Most fuel stations, pipelines and ATMs would stop as soon as the power was lost, shortly followed by land phone lines and mobile phone lines, along with water and wastewater treatment. Medical treatment would also shut down as hospitals would eventually lose electricity too. Emergency services and law enforcement workers would stop working to be with their families, along with power grid workers, making restoration even more difficult. There is also a nuclear concern, as reactors would shut down and melt down. We have become dependent on technology, opening us up to more risks and vulnerabilities. Flares and storms may also affect satellites, as they can be knocked out of their orbit, or their electronics may be damaged.
So the development of understanding of solar activity is vital for helping us to predict when they will happen so that we can be prepared. The most at risk areas are in the north, as that is where solar storms are likely to be most severe. The chances of an event this severe are very low, but it would leave over 100 million people cut off from electrical power.Resilience needs to be built, so that communities can cope with the disaster. Scientists, engineers and government officials are discussing the space weather threat and actions are being taken, but we still don't know when the next strike will occur. But don't worry, us geologists will save the day and figure it all out!

Thursday, 5 December 2013

When Life Gives You Lemons...

A mass extinction event that occurred 252 million years, otherwise known as the Permian-Triassic extinction event, ago may have been, in part, caused by rain that was as acidic as lemon juice. This rain would have killed off plants and organisms around the world, as was caused by sulphur emission from massive volcano eruptions in the Siberian Traps. The rain may have reached a pH of 2, which is as acidic as lemon juice, and would have been sufficient enough to disfigure plants and stop them growing, leading to their extinction. This would in turn led to the extinction of mammals, as the food supply would be dwindling. After the eruptions ended, rain pH levels would have become less acidic within one year.
The BBC and the Natural History Museum have discussed the Permian-Triassic extinction event in more detail. An estimated 93-97% of all species were wiped out in this event, during the three pulses of extinction. There a several other causes of this extinction. The earlier phase was probably due to environmental change caused by the formation of the supercontinent Pangaea. This landmass caused hot and dry conditions to occur worldwide.

Map of Pangaea (courtesy of Geogrify)
The later phase may have been due to a catastrophic impact event, increased volcanism, explosions from the Siberian Traps, release of methane from the sea floor, sea level change, anoxia (lack of oxygen), increasing aridity and a shift in ocean circulation due to climate change. This caused my favourite fossil group to eventually die out - Trilobites!
Trilobites (digressing slightly here, but never mind!) first appeared 521 million years ago, and had over 17,000 species! They lived in the sea, with some burrowing in the mud, some crawling on the seafloor and some swimming in open waters and reefs. Some trilobites were blind, but many had well developed eyes, with some being on stalks so that the ones who buried themselves in mud could just stick their eyes out like periscopes.

Trilobites (courtesy of BBC)