Fossil Lizard Found in Skye 

A correspondent has brought THIS WEB PAGE to my notice. It concerns a tiny lizard, Bellairsia gracilis, which was found on the Isle of Skye a few years ago. It is Middle Jurassic in age. 

Its importance is that it is a "stem" fossil - it split from other lizards just before other groups developed.

This article is a good, but very simplified version, of the academic article in Nature. You can find that HERE. Once again I am amazed at the detail which can be found in fossils with the use of modern instruments. As an example look at the illustration below.

WEGA Excursion to the Lake District - New Low Price!!! 

The Blencathra Centre has recently confirmed that there has been a major reduction in the cost of this excursion!!!

 - now £289!!

So if the cost was putting you off you can still get on the trip. It will run from Friday 21st to Tuesday 25th October. 

At Blencathra FSC

Course Outline - by own transport but car sharing can be arranged.

Friday 21st - travel to Blencathra Field Studies Centre. (Field Studies Council - Blencathra FSC Blencathra, Keswick CA12 4SG, UK) Introduction, meal, overnight accomodation.

The following suggestions for the trip are from the person who will be leading from the FSC James Margeson <j.margeson@field-studies- council.org>

Sat

Morning: School House Quarry (Skiddaw Slate), Mungrisdale. Access is a 100m walk from roadside parking around 20 minutes drive from the centre.

Afternoon: Glenderterra metamorphic aureole. 4km round walk on a bridleway track from the centre. ~50m ascent and descent.

Sun

A day dedicated to the Borrowdale Volcanic Group. This rock group is probably the trickiest to access in terms of walking and parking.

I’m thinking perhaps a walk from the Honister slate mine car park to the quarries on Fleetwith Pike, about 3km and 100m ascent on a vehicle access track. This is one we can discuss though as there are a few different options we could look at.

Mon

I would suggest a visit to Shap Pink Quarry and the Shap Well unconformity. Both involve very short accessible walks. This would suit participants travelling south at the end of the course.

The field locations will be a mix, reflecting the varied and distinctive geology of the Lake District.

Cost £289 per person for residential field course.

In order to confirm your participation in the event, we do need a deposit please of £100 per person, which will be collected by our treasurer Judy Hible (email : judyhible@talktalk.net)

Please advise me, as (temporary, acting) Field Secretary that you are coming on the trip.  Or please email me with any questions: Janet Hellen <jdhellen@btinternet.com> 

Marine "Dinosaurs" - Also Scary 

A correspondent has sent me THIS LINK. It concerns recent discoveries of Late Jurassic fossil mososaurs from Morocco. These grew up to 12 metres long and fed on other mososaurs. The 12 metre beastie has been given the name of Thalassotitan atrox.

Most mososaurs had small teeth, suitable for catching fish. Thalassotitan was shaped more like a killer whale. The fossil bones found with Thalasotitan indicate that it ate other mososaurs and plesiosaurs.

The presence of a top predator like Thalassotitan suggests that the ocean ecosystem was flourishing just before the asteroid which killed the dinosaurs struck.

Thalossotitan skull

What I Did on My Holidays 

Well it wasn't a holiday - it was a Geological Learning Experience in New England, led by Dave Green. It just seemed like a holiday.

I am not going into the details here, I am just going to show some photos of things which caught my geological eye.

The photos on the blog are duplicated in much greater detail elsewhere. You can see them by clicking on the photo. If you click on the photo on the photos.churchard.com page, you zoom in even further. You may need to wait for a few seconds for the larger version to come into focus.

Garnets in a rock, on a traffic island, Hague, New York. Probably from Gore Mountain.

We found some less spectacular garnets near Lake George.

Our garnets 

43 deg 29' 58.55" N, 73 deg 44' 45.73" W

We went to Vinalhaven Island, off the coast of Maine, where a local geologist showed us round. Among the things he showed us were gabbros in granite which he described as being like pillow lavas. Instead of lava flowing into cold sea water, he describes gabbroic magma at 1,200⁰C, flowing into granite magma at 600⁰C. At the moment I cannot think of another explanation.

Blocks of gabbro in a granite matrix.

Blocks of gabbro in a granite matrix. Foot scale.

Also on Vinalhaven he showed us spheroidal rhyolite which is a most peculiar rock. How it forms is, to me, a mystery.

There is a limited outcrop of this rock and the local geologist tells us that specimen collection is forbidden.

Much of our time was spent on the Maine coast which is incredibly complicated with several terranes being plastered onto the the North American Plate. But you can see some very nice rocks.

Finely bedded sediments of the Silurian - Ordovician Kittery Formation (part of the Merrimack Group) on an island in Saco Bay.

43 deg 27' 21.15" N, 70 deg 21' 40.45" W

At Bald Head we saw the same rocks in a more metamorphosed state.

At Bald Head sediments of the Kittery Formation form a syncline.

There are good examples of boudinage.

43 deg 13' 11.62" N, 70 deg 34' 37.68" W

Also we had some rather good scenery to look at. 

Basin Brook reservoir.

44 deg 16' 9.67" N, 71 deg 1' 11.90" W

And the famed New England fall colours could be seen.

Trees became more colourful as our visit progressed.

43 deg 44' 36.39" N, 73 deg 35' 0.37" W

All my photos will be going online soon and I will link to them on the blog. 

Dave Green had put an incredible amount of work into organising this trip and it showed in the fascinating geology we saw.

Nick Chidlaw Field Course 

Nick Chidlaw has asked me to publicise this Field Course he is organising in late November.

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Title:   CONTRASTS IN THE MIDDLE JURASSIC STRATA OF THE COTSWOLDS:  deposition at the margin and near-centre of a subsiding pre-North Atlantic rift basin 

Saturday 19th November  9.00 am - 4.00 pm (sunset at about 4 pm). 

During the Middle part of the Jurassic period, around 170 million years ago,  the crust that became the British Isles was located at about 45 degrees north of the equator and the global climate was much warmer than today, with very limited evidence for ice in the polar regions. The British crust formed a series of islands surrounded by shallow seas, at times only a few meters deep. The islands were well-vegetated and populated by a wide range of animals, dominated by the dinosaurs. In the shallow seas life was also highly varied and included a variety of shellfish and larger animals including marine reptiles. 

At this time, the  Atlantic Ocean had not yet opened; Africa and and South America were joined together and the North Atlantic was beginning to open between what is now north west Africa and the eastern seaboard of the United States. To the north, the crust remained joined, but was characterised by a mosaic of active rift basins in which sediment accumulated in greater quantities than intervening areas where less subsidence took place.  In the British area, many of these basins and intervening areas were present; here, rifting had been most active during the preceding Triassic, but was continuing to influence subsidence and sedimentation in the Early and Middle Jurassic. 

In the west of England and south west Midlands, one of these basins, known as the Severn Basin, was present; it was uplifted and eroded on its north west side in later geological times, so that some of its infill was removed by erosion. Its Middle Jurassic strata now form the Cotswold Hills.  The marginal faults of the rift basin are north-south orientated; those on its western side run along the east side of the Malvern Hills and Forest of Dean, and continue southwards just to the west of the Cotswolds in the Dursley - Wotton under Edge area; those on its eastern side lie along the Gloucestershire - Oxfordshire border.  

This course looks at extensive exposures in the Inferior Oolite Group of Middle Jurassic age in the Cotswolds: one near the western margin of the Severn Basin at Breakheart Quarry, near Dursley, and the other near the centre of the Basin, at Leckhampton Hill, near Cheltenham.  The Inferior Oolite Group of the Cotswolds is divided up into many rock-stratigraphic units, enabling detailed comparisons to be made between one area and another. At the two locations to be visited can be demonstrated how the strata change in thickness and type, with some of the rock units not present at the basin margins. Breakheart Quarry is to be visited first in the morning , then we travel to Leckhampton Hill for the afternoon.   

No previous knowledge of geology or the area will be assumed for those wishing to enrol on the course.   

A handout outlining the day’s programme, including location sketch map, illustrated geological history and written log of the succession of strata, will be forwarded in advance of the course to those enrolled.

Note that enrollees will need to:

*     Arrange their own transport

*     Bring a packed lunch and any refreshments (e.g. flask of coffee, fruit juice, mineral water etc.)

*     Wear strong footwear with good tread and ankle support, and have waterproof clothing if weather is poor.

*     Hard hats will be needed at the second location for this course - they will not be needed for the first. If you do not have a hard hat, I can lend you one (let  me know in advance).

Attendees will be insured against accident for the duration of the course. 

Tuition fee: £30.00 

Contact tutor Dr Nick Chidlaw nickchidlaw@gmail.com to enrol and for any queries. 

Deadline for course viability: Friday 4th November . If the course has become viable (minimum of 10 enrolments) by this date, enrolments will be able to continue until Saturday 12th November.

Breakheart Quarry, Dursley, Glos.  View showing the lower quarry and impression of the extensive nature of the workings. Here it is possible to walk across sea beds that have been bored into by marine organisms and which have the remains of oysters attached . Quarrying has long ceased; the  site is now a run by a registered charity Breakheart Community Project; it is open to the public.  

Workings in the upper part of the quarries on Leckhampton Hill, Cheltenham, Glos.  We examine this section, together with others below and above. The Hill  has many footpaths, giving full public access.