Monday 30 December 2019

DOWN TO EARTH EXTRA - JANUARY 2020


DOWN TO EARTH EXTRA - January 2020


You can get the latest edition HERE.



PROPOSED TWO INDOOR COURSES IN MARCH 2020

Proposed Two Indoor Courses in March 2020

Nick Chidlaw has contacted me about two courses he would like to run in Thornbury in early March.

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Information on courses
I am currently offering two 1-day courses for next March; these are indoor-based, and describe field areas where I have organised events in the past. These courses may be attractive to people who are not in a position to visit these areas e.g. insufficient time available because of family / work commitments, or health problems.
Details of each course is provided at the bottom of this message.
Each course would comprise powerpoint-based lectures, together with examination of hand specimens of relevant mineral and rock types, and published geological maps of the field areas. The hand specimens have been collected by the tutor in the field areas described.
A handout outlining the day’s programme containing sketch maps and other relevant drawings, stratigraphic tables and a list of optional reading,  would be provided on each course. No prior knowledge of geology or the study areas would be assumed.  
Please note that these courses are run on the same weekend and in the same venue, but are independent of one another – you can enrol on both if you wish to, or one of them, according to your interests / availability.
Venue for both courses
The Buckingham Room (single storey building by the car park) at The Chantry, 52 Castle Street, Thornbury, South Gloucestershire. BS35 1HB. See website for further details www.thechantry.org.uk

I will provide Information on accommodation options to those who live beyond reasonable commuting distance. 
On each course, attendees would bring their own packed lunch and other refreshments, or go into the town for lunch.  
Tuition Fee 
£27.00 per person for each course.
Payment of Tuition Fee
Cheque payable to me sent to 8, Silver Street, Dursley, Glos. GL11 4ND. Bank Trans can be arranged if required (let me know).
Deadline for viability of both courses 
Saturday 1st February (5 weeks before the courses are due to run).
Both courses to have a minimum of 10 attendees / fee equivalent. Maximum of 30 attendees on each course. If viability for either or both courses is reached, those enrolled will be informed on the deadline date and arrangements will be able to continue. Further enrolments can be made up to 1 week before the courses are due to run. If the minimum number of attendees / fee equivalent is not reached for either course by the deadline, that course will be cancelled and fees received will be returned to those who have sent them in.
Any queries, do get in touch with the tutor nickchidlaw@gmail.com

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PERMIAN STRATA IN NORTH EAST ENGLAND: continental dune fields, marine reefs and karstic collapse


Permian Slump Olistolith, Trowe Point

Saturday 7th March 10.00 am – 5.00 pm
During the Permian period (299 – 252 million years ago), the crust that became the British Isles was located just north of the equator, under a hot, dry climate. Here, continental environments characterised the period, except in parts of north, where in Mid and Late Permian times episodic marine incursions laid down mostly carbonate sediments with interbedded evaporites. In the north east of England, Permian strata of both continental and marine origin are well represented and exposed, particularly along the attractive coastline. They are impressive, reflecting a variety of environments: continental dune fields, succeeded by both deep and shallow water shelf deposits, including an extensive bryozoan reef belt 20 miles long and up to 100m high. In some of the marine strata, fish, land plants and land reptile remains are preserved. Localised as well as extensive wholesale landsliding of the marine shelf  is evident. In what are now the onshore areas, the evaporites (chiefly halite and anhydrite) were subsequently mostly dissolved, forming impressive collapse features. Bizarre concretionary structures, which may have developed in much more recent geological times, characterize some of the carbonates.      

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METAMORPHISM AND MINERALIZATION IN THE BRISTOL – MENDIP AREA

Pb & Zn Ores with Calcite, Radstock Museum

Sunday 8th March 10.00 am – 5.00 pm
Following the end of the Carboniferous period around 300 million years ago, the area of the earth’s crust that became the British Isles began to stretch and heat as the North Atlantic Rift basin began to form. In the west of England, subsiding rift basins developed where the Cotswolds and Somerset Levels now lie. Between these places, in the Bristol – Mendip area, the crust was under tension at times, causing opening of lines of weakness including faults, joints and fissures. Into these created spaces, and cave systems, descending and ascending chemical –rich fluids accumulated, cooling and crystalizing to form mineral deposits. They include deposits of iron and manganese in Triassic times, and chiefly lead and zinc sulphides in Middle Jurassic times. Associated with the latter, other fluids spread extensively through porous strata in some areas, metamorphosing them to a silica-rich rock. Subsequently, many of these mineral deposits became of significant economic importance to man. This course will familiarise attendees with the history and character of this mineralization, and the impressive variety of mineral types that have been collected in the area in the past.  

Saturday 14 December 2019

16th December 2019 to 5th January 2020


NEXT WEEKS EVENTS

16th December 2019 to 5th January 2020


THE FOLLOWING IS AN EXTRACT FROM BRISTOL AND WEST COUNTRY GEOLOGY CALENDARS

MORE DETAILS CAN BE FOUND IN THE BRISTOL AND THE WEST COUNTRY CALENDARS AND ON THE WEB SITES OF THE RELEVANT SOCIETY OR ORGANISATION.


MONDAY 16TH


tuesday 17th

SMFS Evening Meeting
When
Tue, 17 December, 19:30 – 21:30
Where
The Friends' Meeting House, 1A, Ordnance Rd, Southampton. SO15 2AZ (map)
Description
“Geological Cartoons; historical & modern” – presentation by our Chairman Phil James.

Members’ Display Table: Geological Funnies!

Details at http://www.sotonminfoss.org.uk/smfsprog.htm

Wednesday 18th


Thursday 19th

Thornbury Geology Group, 7.30pm, The Chantry, Thornbury
When
Thu, 19 December, 19:00 – 21:30
Description
Thornbury Geology Group, 7.30pm at The Chantry, Thornbury, and every 3rd Thursday in the month.  

Friday 20th


Saturday 21st


sunday 22nd


monday 23rd

Geostudies - Annual Dinner
When
Mon, 23 December, 19:30 – 22:00
Where
The Watersmeet Hartpury, Gloucester GL19 3BT, UK (map)
Description
Annual Geological Reunion Dinner at Watersmeet, Hartpury 7.30 for 8.00pm 

tuesday 24th


WEDNESDAY 25TH


THURSDAY 26TH


FRIDAY 27TH


SATURDAY 28th


SUNDAY 29th


MONDAY 30th


TUESDAY 31st

WEDNESDAY 1st


THURSDAY 2nd


FRIDAY 3rd


SATURDAY 4TH


SUNDAY 5TH



Sunday 8 December 2019

Dorset Building Stone

Dorset Building Stone

A correspondent has brought THIS FASCINATING SITE to my notice. And it has an accompanying BLOG. So far I have just skimmed a few articles but I am impressed by the thoroughness of the coverage. 

I now know that the Parish Church of St. Peter and St. Paul in Blandford was built by the Bastard brothers using Upper Greensand but they placed the bedding vertically rather than in the natural horizontal position and therefore it has weathered badly. Despite their unfortunate name the brothers produced the finest Georgian church outside London and rebuilt the town after a devastating fire in 1731. 

The site is full of such interesting detail and is obviously a labour of love - well worth looking at - again and again!



Saturday 7 December 2019

9th to 15th December 2019


NEXT WEEKS EVENTS

9th to 15th December 2019


THE FOLLOWING IS AN EXTRACT FROM BRISTOL AND WEST COUNTRY GEOLOGY CALENDARS

MORE DETAILS CAN BE FOUND IN THE BRISTOL AND THE WEST COUNTRY CALENDARS AND ON THE WEB SITES OF THE RELEVANT SOCIETY OR ORGANISATION.


MONDAY 9th

Geostudies - Lecture Series - Ordovician
When
Mon, 9 December, 19:30 – 21:30
Where
Wynstones School, Stroud Road, Whaddon, Gloucester (map)
Description
Geology of the Ordovician Period. 

The last Phanerozoic geological period to be named, after a bitter struggle between Murchison and Sedgwick. Lasting from 
485 to 444Ma ago, this period saw the enormous radiation of new forms of life and the earliest colonisation of the land by primitive plants “The Great Ordovician Biodiversification Event” . The two halves of Britain were separated by the Iapetus Ocean, but both were tectonically extremely active. The supercontinent of Gondwana drifted across the South Pole, possibly triggering a short and unusual (high CO2) glaciation and the second biggest mass extinction of life at the end of the period. As usual there is considerable debate about aspects of this period. 

Starts Mon 16th September  for 10 weeks (not 28th Oct nor 4th Nov nor 2nd Dec), until 9th December   Held at Wynstones School, Stroud Road, Whaddon, Gloucester from 7.30-9.30pm on Mondays. 

Cost £75 (including tea, coffee etc at break time!).  

TUESDAY 10th

WEGA Christmas Lunch
When
Tue, 10 December, 12:00 – 14:00
Where
The Eastfield Inn, 219 Henleaze Rd, Bristol BS9 4NQ, UK (map)
Description
Xmas lunch 12 noon at Eastfield Inn, Henleaze - please book through Treasurer
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Cardiff University Lecture - Volcanoes—all you need to know!
When
Tue, 10 December, 18:30 – 20:00
Where
School of Earth and Ocean Sciences will be held in the Wallace Lecture Theatre (0.13), Main Building, Cardiff University, Park Place, Cardiff CF10 3AT (map)
Description
The secrets of Vulcan: the hidden world of underwater volcanoes.    Chris MacLeod,  Cardiff

The 2019-2020 monthly Tuesday evening lecture series in the School of Earth and Ocean Sciences will be held in the Wallace Lecture Theatre (0.13), Main Building, Cardiff University, Park Place,
 Cardiff CF10 3AT.  Lectures begin at 18.30.  Booking is not needed.  Should you require the Q&A sessions to be in Welsh, please email edwardsd2@cardiff.ac.uk at least two weeks before the event.

Did you know that the majority of volcanic eruptions – maybe even 90% – occur under water and of which we are largely unaware? There remains a very great deal we don't know about volcanoes, but many exciting new insights are emerging from ongoing research. This lecture series will encompass the diversity of volcanoes, their functioning and products, together with the nature of eruptions and their attendant problems of predictions plus their ensuing past and present environmental and biological impacts.

WEDNESDAY 11TH


Thursday 12th

Geostudies - Lecture Series - Miscellany
When
Thu, 12 December, 18:30 – 20:30
Where
John Kyrle High School, Ledbury Rd, Ross-on-Wye HR9 7ET, UK (map)
Description
Understanding the Earth – a Geological Miscellany

Thursday September 19th, 6.30-8.30pm, running for 10 weeks at the Adult Education Centre, John Kyrle High School until 12th December (missing out 24th, 31st October and 7th November) covering the following topics: Geological maps and structures, and their relationship to landscape development; Tectonics, mountain building and their effects on landforms; Geological resources – formation , occurrence and exploitation; Climate change in a geological context. 

Cost £75, including drinks at break time. 

friday 13th

Cheltenham Mineral and Geological Society - Lecture
When
Fri, 13 December, 19:00 – 21:00
Where
Shurdington at The Century Hall (map)
Description
Sale, Quiz,  and Raffle   

saturday 14th


sunday 15th



Thursday 5 December 2019

Did a Rainy Spell Start Dinosaur Evolution?

Did a Rainy Spell Start Dinosaur Evolution?

THIS ARTICLE tells a rather charming story of how a chance encounter led to a theory that a wet period in the mostly dry Triassic (the Carnian) encouraged (or demanded) evolution. Some crinoids died. Corals became more modern, mammals may have appeared. And dinosaurs - a rather rare group - evolved into a diverse group.

The article has lots of detail - was the Wrangellian eruptions in western North America responsible for global warming which led to increased precipitation? 

But now the Carnian is being intensively studied wherever it is found, including the Dolomites, which allows me to show one of my photos of a mountain with some red stuff - is that the Carnian?


How Life Survived Snowball Earth

How Life Survived Snowball Earth

THIS ARTICLE in the New York Times, based on THIS ARTICLE in a scientific journal (subscription required), describes research which found that some areas beneath the ice, separated from the atmosphere, had sufficient oxygen to sustain life. These areas were near the shoreline, land against sea ice.

The researchers reckon that glacial meltwater, running into the sub-ice oceans carried oxygen in sufficient quantity to let aerobic life to survive.

The articles describe the research which led to this conclusion, in much more detail than I give and the N Y Times article is very easy to read.

Credit...Chris Butler/Science Source