Friday 26 October 2012

Fossil Rock Anthem

What do you think of this?

Limbed Fish

Recent discoveries of advanced fish-like stem-tetrapods (for example, Panderichthys and Tiktaalik) have greatly improved our knowledge of the fin-to-limb transition. However, a paucity of fossil data from primitive finned tetrapods prevents profound understanding of the acquisition sequence of tetrapod characters. However, a new stem-tetrapod (Tungsenia paradoxa gen. et sp. nov.) from the Lower Devonian (Pragian, ~409 million years ago) of China, extends the earliest record of tetrapods by some 10 million years. Sharing many primitive features with stem-lungfishes, the new taxon further fills in the morphological gap between tetrapods and lungfishes. The X-ray tomography study of the skull (photo) depicts the plesiomorphic condition of the brain in the tetrapods. The enlargement of the cerebral hemispheres and the possible presence of the pars tuberalis in this stem-tetrapod indicate that some important brain modifications related to terrestrial life had occurred at the beginning of the tetrapod evolution, much earlier than previously thought.

Thursday 18 October 2012

West Country Geology field programme 2013

A meeting was held at Box during August where it was agreed by representatives of BNS Geology Section, Bath Geological Society and West of England Geologists’ Association that, as a one-year trial, the three societies will organise a joint programme of field meetings for 2013.  This should be of benefit to members of all the societies, as we can all draw on a wider base of expertise, avoid clashes and repetitions, and ensure good attendance.  I am sure that this will be a positive improvement for all involved.
Please add any comments, thoughts and suggestions to this post.

24th October - The Forgotten Engineer

'The Forgotten Engineer'
19:30 Wednesday 24 October
Speaker: Trevor Thompson
This an illustrated talk on Charles Richardson (1814-1896) former President of the Bristol Naturalists’ Society Engineering Section. His many engineering feats, some of which are known to us all, could not have been achieved without the required knowledge and understanding of geology.
Talks take place in the S H Reynolds lecture theatre, Wills Memorial Building, University of Bristol, BS8 1RJ.
Further details - Bristol Naturalists' Society - geology

Thursday 11 October 2012

21st October Itchington Lane clearance

John Toller is organising a clear-up of the exposure at Itchington Lane (Nr Thornbury) on Sunday 21st October
Map Ref ST 655877
Simple gardening tools will suffice. Bring gloves, wellies and a drink
The limestone outcrop is next to "Bristol's Time Gap" geological information sign, adjacent to road bridge under M5 motorway.
Please let John know if you may be free - otherwise he can try for an alternative date - email.

Amazing sight in the South Pacific

A reader sent the link to this video clip. He says some of the descriptions of the material are a bit suspect!

Wednesday 10 October 2012

Somerset Geology Group - Autumn Newsletter

Please click here to download the Somerset Geology Group Autumn Newsletter from Hugh Prudden.

'Ammonite order' in architecture?

What are those on top of the fluted pilasters that bookend the fa├žade in the photo above? Ammonites!
The ‘ammonite order’ was the brainchild of George Dance, who used it in London in 1789. It was taken up enthusiastically by Amon Wilds and his son, also called Amon, builder-architects who did a lot of work in Sussex, especially Brighton. Perhaps they liked ammonites because the name afforded the opportunity for a visual pun. Fossil-collecting was already a popular pastime by 1810, and ammonites, or ‘snake stones’ as they were often called, were prized by collectors. Their likeness fits wonderfully, if eccentrically, on top of the pilasters on this Lewes house, and no doubt acted as a kind of advertisement for the builders. In 1816 Castle Place was bought by a Dr Gideon Mantell, who was a geologist. No doubt he liked the ammonites too. 
Read more

Fossil reveals spider mid-strike

A hundred million years ago, an amber flow spoiled a spider’s day: it had waited, possibly for hours, to ambush a wasp in its web, and just as it decided to strike, spider, wasp and web were all trapped forever.
The good news for us is that it’s turned up at a dig in Myanmar's Hukawng Valley.

The early Cretaceous fossil preserves – with stunning clarity – the juvenile spider about to make a meal of a parasitic wasp that was trapped in its web. The spider is an orb weaver and relatives still exist today, although the kind in the amber is extinct. The wasp is a relative of species which today are parasites on both spiders and their eggs. There are also fifteen unbroken strands of the spider’s web also preserved in the fossil.

Monday 8 October 2012

Somerset Earth Science Centre and Tedbury Camp

Because of blasting in the quarry and the loss of the little Silurian fossils, Bath Geological Society's field trip on Friday 12th October has changed. We shall visit the Centre in the morning and tour one of the local quarries and then visit Tedbury Camp in the afternoon. There are further details on the website.
Booking is essential because of space in the Centre's minibus.
Contact: 07712 776117 or email.

Friday 5 October 2012

Scary-looking cat-sized dinosaur

A two-foot long dinosaur with the beak of a parrot, fangs and covered in bristly quills is the latest new dinosaur to be identified. The Pegomastax africanus scampered around the earth 200 million years ago. The new dinosaur, Pego, is a member of the Heterodontosaur family, and measured less than 1m and weighed less than a small cat. It had a beak and fangs and looked terrifying according to the mock-up created by the University of Chicago.
A Pegomastax skeleton had been sitting in a drawer in Harvard for the past 50 years, embedded in a piece of red rock. The rock was unearthed during a dig in South Africa in the 1960s.
Palaeontologists have speculated that the beaked two-legged cat creature may also have been covered in porcupine quills, saying that it would have been like a "nimble two-legged porcupine".
The volcanic ash in which the skeleton was buried has preserved hundreds of bristles that spread from Pego's neck to the tip of its tail.
The fangs tucked behind the beak - unusual in herbivores - were likely used for sparring and mating competitions. Maybe they were used mainly for nipping, in the manner of today's fanged deer.

Break-up of a plate?

An April 2012 earthquake in Indonesian may signal the breakup of the Indo-Australian tectonic plate and gave the earth's crust such a shaking that earthquakes happened all over the globe. That's the thrust of new articles in Nature, one of which analyses the quake and says the 11 April 2012 event had an extraordinarily complex four-fault rupture. The event was also noteworthy for being a slip-strike, an unusual type of earthquake that sees the crust split. Subduction, which happens when one plate slides beneath another, is a more common source of earthquakes. The article notes that “Occurrence of great intraplate strike-slip faulting located seaward of a subduction zone is unusual” and goes on to explain that the event started with one shock that "initially expanded bilaterally with large slip (20–30 metres)” before a “bilateral rupture was triggered on an orthogonal left-lateral strike-slip fault … that crosses the first fault.” Next came “westward rupture on a second … strike-slip fault” and the event finished when “rupture was triggered on another ... fault about 330 kilometres west of the epicentre crossing the Ninetyeast ridge.”

Tuesday 2 October 2012

Ancient streambed on Mars

NASA's Curiosity Mars rover has made its first major science discovery.
Water—fast-running and relatively deep—once coursed over the now bone-dry surface; a finding based on the presence of rounded pebbles and gravel near the rover's landing site in Gale Crater.
What's more, the team has concluded that the water was present for "thousands or millions of years," though the researchers said it would take far more research to get a clearer picture of the flow's longevity.
The discovery is the first proof that surface water once ran on Mars. Planetary scientists have hypothesized that the cut canyons and river-like beds photographed by Mars satellites had been created by running water, but only now do researchers have on-the-ground confirmation—and the promise of learning much more about the nature and duration of the water flows.
"We've now identified pebbles and gravel at the landing site that clearly have been carried down by water, have been broken down and very much smoothed out," said William Dietrich, a geomorphologist working with the Curiosity imaging science team. "This is the beginning of our process of learning how much water was running and how long this area was wet."
Click here for full account.