Saturday 29 February 2020

3rd to 9th March 2020


NEXT WEEKS EVENTS

2nd to 8th March 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 3rd

Geostudies Lecture Course - Germany
When
Mon, 3 February, 19:30 – 21:30
Where
Wynstones School, Stroud Road, Whaddon, Gloucester (map)
Description
The Geology of Germany 

 Monday 13th for 10 weeks (not 17th Feb) until 23rd  March. Held at Wynstones School, Stroud Road, Whaddon, Gloucester from 7.30 - 9.30pm on Mondays. 

Like Britain, Germany consists of a number of exotic Terranes, derived from different continents and amalgamated together by plate tectonic collisions. Northern Germany is part of Avalonia, which amalgamated with the East European Craton (Baltica) along the Tornquist suture in the east. A great deal of this area is plastered by thick Quaternary glacial sediments. 

Central Germany is part of Armorica, which collided with the north during the Variscan orogeny. There is, in places, thick Mesozoic unconformable cover. The extreme south is part of the Alpine orogeny, but its effects were transmitted northwards to affect and reactivate older structures. There was extensive volcanic activity during the Tertiary, and some famous asteroid impact sites. 

Cost £75

tuesday 4th


wednesday 5th


thursday 6th

Bath Geol Soc - AGM and Lecture
When
Thu, 6 February, 19:00 – 21:00
Where
16 Queen Square, Bath at the kind invitation of the Bath Royal Literary and Scientfic Institution. (map)
Description
Annual General Meeting, 2019
AGM will start at 7.00 p.m. followed by the lecture at 7.30p.m. Please note that the AGM is for members only. Visitors are welcome to attend the evening's lecture.
Did Ocean Acidification kill off Calcifiers at the end of the Cretaceous?
Prof. Toby Tyrrell, University of Southampton
Ammonites went extinct at the time of the end-Cretaceous asteroid impact, as did more than 90% of species of calcium carbonate-shelled plankton (coccolithophores and foraminifera).Comparable groups not possessing calcium carbonate shells were less severely affected, raising the possibility that ocean acidification, as a side effect of the collision, might have been responsible for the apparent selectivity of the extinctions (calcium carbonate dissolves in even slightly acidic seawater). We investigated whether ocean acidification could have caused the disappearance of the calcifying organisms. I will describe the results of some modelling work we carried out. We simulated various scenarios for how the impact could have produced more acidic seawater (different possible mechanisms from impact to acidity). The results suggest that, although acidification was quite extreme in some scenarios, nevertheless it was probably not the primary reason why so many calcifiers went extinct.
------------------------------------------

Geostudies Lecture - Uniformitarianism
When
Thu, 6 February, 19:30 – 21:30
Where
The Chantry, Thornbury (map)
Description

The Limits of Uniformitarianism.


The science of geology is heavily dependent on the principle of uniformitarianism – the idea  that geological conditions and processes have remained substantially unchanged through geological time, meaning that we can interpret the past on the basis of our understanding of the geological present. But how accurate is this principle? To what extent were conditions and processes different in the past? Are present conditions and processes typical? How well do we understand present processes? And there are also spatial features to consider; A casual examination of a modern sedimentary or volcanic environment reveals rapid and wide-ranging changes in facies over a small area. Our evidence of past environments is largely based on small, possibly unrepresentative, exposures of tiny fractions of those past environments. Are we justified in using evidence from the past to interpret the present and future, such as climate change?  Held at The Chantry, Thornbury, in the Hanover Room.  First meeting 7.30 – 9.30, Thurs 16th  January until April 2nd  (not Thurs 20th Feb or 19th March). Cost £75


Programme

What do we mean by Uniformitarianism? Origin of the term and the historical context in which it arose and developed as a counter to “Old” Catastrophism.

What are the main problems with Uniformitarianism? The rise of “New” Catastrophism in the later part of the 20th century. Problems of direction, cyclicity, punctuation, gradualism in the following fields of geology:

Uniformitarianism and sedimentation. Have conditions changed over geological time? How representative in terms of coverage and completeness is the sedimentary record?

Uniformitarianism and volcanicity, earthquakes, intrusion and landslides

Uniformitarianism and the solar system – external processes affecting earth geology

Uniformitarianism and major environmental change (such as climate and sea level changes)

Uniformitarianism, evolution and mass extinction  

Uniformitarianism and tectonics – was plate tectonics a relatively young development? Is the Wilson (supercontinent) Cycle real?

Geomorphology and Uniformitarianism

Is the present the key to the past? (or in reverse?)


friday 7th


saturday 8th


sunday 9th

OUGS Severnside - AGM and Talks
When
Sun, 9 February, 10:00 – 16:00
Where
: Langstone Village Hall, Old Chepstow Road, Langstone, Newport NP18 2ND, South Wales (map)
Description

Branch Annual General Meeting

Branch AGM followed by a number of short talks from members.

This is a winter social event for our branch members.

Doors open at 10 am, and the AGM itself will start at 11 am. This will include a short presentation describing the various events we held during 2019.

Tea and coffee will be available throughout the day. A buffet lunch will be provided after the AGM, but you are welcome to bring your own packed lunch. Please note that there is no charge for this event.

After lunch we will have a number of short talks from members. We would love to hear from anyone who would like to give a talk about their own geology visits, for example while on holiday. There will be a projector available if you wish to show some photos or provide a short presentation (eg in Powerpoint), although a talk with some rock specimens only would be equally welcome. A talk can be quite brief and should not exceed 15-20 minutes. Please contact Norman (details below) if you would like to share your geological experiences with other members.

The branch library will be available throughout the day and you will be able to borrow geology-related books from its large collection, as well as return any books borrowed previously.

Please let Norman know if you plan to attend (details below) so that we can ensure sufficient food and drink are provided for everyone.


GeoStudies in Mallorca

GeoStudies in Mallorca

I have recently returned from an excursion to Mallorca, arranged by Geostudies. This article is intended to give a broad overview of the trip with a few pictures of the highlights. No great geological insights are given - only a flavour of the geology of Mallorca.

The areas covered are indicated in the following map.


We arrived on the island on the morning of Monday 17th February. After lunch our (small) bus took us to the peninsula with Alcudia at its base. Highlights were a nappe of Upper Jurassic with a filling of Lower Cretaceous.

Nappe - the line of pine trees mark the Lower Cretaceous. Above and below are cliffs of Upper Jurassic limestone.

And chevron folding.

Chevron folding


Tuesday took us to the South-West side of the island where we looked at the oldest rocks - Triassic - Bunter, Muschelkalk and Keuper. It was a dull day and the rocks, while being very interesting, were not photogenic. But we did find a nice restaurant atop 1,000 foot cliffs. And it had good coffee.




Wednesday was our only day without a visit to a beach. Instead we went to the Cuber reservoir to look at Jurassic limestones forming the highest peaks of the island.

Puig Major (1,436m) seen across the Cuber reservoir. Note the road hairpinning its way up the Jurassic limestone mountain. The dome on Puig Major protects radar antennae.

The spectacular scenery was not what I was expecting on Mallorca.


Thursday was intended to be a leisurely walk along a beach looking at Oligocene and Eocene sediments. We should have been warned as getting down to the beach was complicated as our GA guide (30 years old) did not specify how to get there. But once on the beach we were fascinated by looking at conglomerates, micrites, marls, lots of faulting and shattering and, not least, some oncoliths and stromatolites.

But the walking was not easy. There was a lot of scrambling over boulders. And then the beach came to an end! Going back was not an attractive option, so we decided to wade the short distance to where we knew there was a civilised beach with a restaurant.
Extreme beach geology. Photo taken with my phone - that is my finger on the lower left.

Fortunately the water was reasonably warm. This was the non-geologic highlight of the trip.

Friday took us to Randa and Cala Pi. At Randa we looked for nummulitic limestone and found it in an abandoned quarry. Also turbidites. We retreated from the roadside exposure to avoid being run over by the multitude of high speed cyclists racing up and down the steep road.

Examining turbidites at Randa

Then to Cala Pi which is a rather beautiful spot with the added attraction of lots of fossil corals.

Cala Pi

Saturday was spent looking at Cretaceous limestones on the North East corner of the island. These were much deformed by tectonism and were covered in may places by Recent arenites.

Cretaceous limestone covered by recent sand dunes

Our last day, Sunday, was spent on the Formentor Peninsula, which has some of the most spectacular scenery on the island. It is dominated by thrusting. Generally it is Lias limestone over Oligocene/Miocene shales. The best example was beneath a hotel in Cala San Vicenç.

Lias limestone thrust over Oligocene/Miocene shale.

Further north we saw tall, white, limestone cliffs towering over blue seas.

The Formentor Lighthouse at the end of the peninsula.

On the way back down the peninsula we stopped at the road tunnel and looked at yet another thrust plane lowering over the road.

Thrust plane 

And then the next day we flew home. 

I hope this race through our trip to Mallorca whets your appetite to visit this wonderful island.

More About Zealandia

More About Zealandia

THIS ARTICLE gives an introduction to the (mostly) sunken continent of Zealandia which lies to the east of Australia and appears above the waves in New Zealand and New Caledonia. 

There is new information garnered from six new boreholes drilled from the ship JOIDES Resolution.

The expedition drilled for samples at six sites, marked on this map with stars. IODP, Author provided
The writers conclusions are that part of the reason for Zealandia's sunken state is that tectonic forces stretched and thinned the continents crust as it was being separated from Gondwana 85 million years ago.

But they also postulate a “subduction rupture event” – a process similar to a massive slow-moving earthquake – spread around the whole of the western Pacific about 50 million years ago.

You can read more about this in the scientific paper on which the introductory article is based, You can get it HERE

Wednesday 26 February 2020

Unpaid Geological Internship Available

Unpaid Geological Internship Available

The following has been forwarded to me.

---------------------------------------------------------------------------

Opportunities for Undergraduate and Post-Graduate Geological Internships

The Somerset Geology Group (SGG), in partnership with the Somerset Environmental Records Centre (SERC), is undertaking a project to review Somerset’s 230 Local Geological Sites (LGS). These were formerly designated as Regionally Important Geological Sites (RIGS). The project is supported by several organisations including The Curry Fund of the Geologists’ Association, Exmoor National Park Authority, and Somerset Archaeological & Natural History Society.

To complete the desk-based site research and fieldwork for this review, SERC are seeking applications from geology undergraduates and post-graduates. The successful interns will work on a voluntary basis, but training and travelling expenses to site will be provided. The availability of an academic email account (.ac) would be useful. SERC is based at the Somerset Wildlife Trust HQ in Taunton, but interns will be required to work throughout Somerset.

We are seeking individuals able to commit at least three months of their time to the project. This is year 4 of the 5 year project, and our focus in 2020 will be on sites in South Somerset. 
This opportunity will be particularly suitable if you:
  • have studied geology for at least two years (or similar)
  • have a residential base in or near Somerset
  • are on a degree course offering year-out placements
  • are interested in volunteering on the project and can envisage being able to commit a reasonable number of volunteer weeks (or days over a longer period of time)
  • enjoy web- and literature-based research in geology (particularly the importance of geological sites) and are comfortable with electronic-based form completion and basic GIS use (e.g. Google maps/Google Earth/Digimap)
  • are interested in developing your skills in writing site assessments based on the site research backed up by field investigation of each site
  • would like to be part of a project contributing to Earth Science conservation
  • would simply like to keep in touch with Earth Science conservation, as part of our SGG network

To apply, please send a 2-page CV and short covering letter to Leon DeBell (SERC Manager) at Leon.DeBell@Somerc.com by 3rd May 2020, copying in somersetgeology@gmail.com. Please indicate whether or not you hold a current full driving licence. For further details or an informal discussion, phone Leon DeBell on 01823 652446.   








Small Earthquakes on Mars

Small Earthquakes on Mars, No One Hurt, Many Interested

It is reported HERE that NASA's InSight probe has detected earthquakes on Mars.



The sound of the first detected Marsquake, 7 April 2019, speeded up 60 times. In this extract, there is first noise from the local wind, then the seismic event itself, and the spacecraft’s robotic arm as it moves to take pictures.

The best guess for the location of the largest quakes (less than 4 on the Richter scale, so quite small by Earth's standards) is the Cerberus Fossae.

600 km wide region of Mars, with the fractures known as Cerberos Fossae running diagonally from westnorthwest to eastsoutheast. ESA/DLR/FU Berline (G Neukum)

Mars does not have plate tectonics so these quakes are the result of Mars's crust experiencing stresses, caused by local deformation, leading to fractures similar to what occurs in earthquakes in the interiors of Earth’s continents – well away from plate boundaries.


Saturday 15 February 2020

17th February to 1st March 2020


NEXT WEEKS EVENTS

17th February to 1st March 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 17TH

Geostudies Field Course - Mallorca
When
17– 24 Feb 2020
Description

The Geology of  Mallorca 

 Mallorca  is an extension of the Alpine range of the Betic Cordillera. Rocks ranging in age from the Carboniferous to  the Pleistocene are mainly sedimentary and have been severely affected by thrusting and folding during the Miocene, producing two ranges of mountains – the Sierra  Norte and Sierra de Levante, separated by a fault guided valley preserving younger sediments. 

Dave Green, Joys Green Farm, Forge Hill, Lydbrook, Glos GL17 9QU  Tel 01594 860858   
e-mail davegeostudies@gmail.com 

tuesday 18th

GEOSTUDIES FIELD COURSE - MALLORCA
------------------------------

Geol Soc Western - Lecture
When
Tue, 18 February, 18:00 – 20:00
Where
The Hub, 500 Park Ave, Aztec W, Almondsbury, Bristol BS32 4TR, UK (map)
Description
Talk - The Engineering Geology and Geomorphology of Hot Deserts by Professor Jim Griffiths, Plymouth University  

The Western Regional Group is pleased to welcome Professor James Griffiths, Emeritus Professor of 
Engineering Geology & Geomorphology, University of Plymouth. Jim received the prestigious Glossop Medal 
from the Geological Society in 2013 and has over 15 years’ industry experience and over 20 years in 
academia working in geology and geomorphology.  

Over the past 40 years considerable understanding and experience has been gained of the 
geomorphological processes and ground characteristics peculiar to hot desert regions, and the effects these 
have on engineering design and construction. This work was summarized by Engineering Group Working 
Party on Hot Deserts in EGSP 25 (Walker 2012). The Working Party brought together a team of practicing 
engineering geologists, applied geomorphologists, geotechnical and civil engineers with a wealth of varied 
but complimentary experience of working in hot deserts. The report covered: desert environments; processes 
and landforms; hazards and the desert ground model; soil and rock description and characteristics; site investigation; engineering  behaviour of desert soils; construction  materials; and engineering design and  construction.   

This presentation will be on the engineering  geological and geomorphological aspects of  hot deserts conditions and the way these  disciplines inform engineering design. The  presentation will be by Professor Griffiths who  co-authored three of the ten chapters in the  report and will draw on the all aspects of the  findings of the Working Party.  

Walker, M.J., (ed.) 2012. Hot Desert Engineering Geology and Geomorphology.  
Geological Society Engineering Geology Special Publication, 25, pp.424. 

wednesday 19th

GEOSTUDIES FIELD COURSE - MALLORCA

thursday 20th

GEOSTUDIES FIELD COURSE - MALLORCA
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Thornbury Geology Group, 7.30pm, The Chantry, Thornbury
When
Thu, 20 February, 19:00 – 21:30
Description
Thornbury Geology Group, 7.30pm at The Chantry, Thornbury, and every 3rd Thursday in the month.  

friday 21st

GEOSTUDIES FIELD COURSE - MALLORCA

saturday 22nd

GEOSTUDIES FIELD COURSE - MALLORCA

sunday 23rd

GEOSTUDIES FIELD COURSE - MALLORCA

monday 24th

GEOSTUDIES FIELD COURSE - MALLORCA
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Geostudies Lecture Course - Germany
When
Mon, 24 February, 19:30 – 21:30
Where
Wynstones School, Stroud Road, Whaddon, Gloucester (map)
Description
The Geology of Germany 

 Monday 13th for 10 weeks (not 17th Feb) until 23rd  March. Held at Wynstones School, Stroud Road, Whaddon, Gloucester from 7.30 - 9.30pm on Mondays. 

Like Britain, Germany consists of a number of exotic Terranes, derived from different continents and amalgamated together by plate tectonic collisions. Northern Germany is part of Avalonia, which amalgamated with the East European Craton (Baltica) along the Tornquist suture in the east. A great deal of this area is plastered by thick Quaternary glacial sediments. 

Central Germany is part of Armorica, which collided with the north during the Variscan orogeny. There is, in places, thick Mesozoic unconformable cover. The extreme south is part of the Alpine orogeny, but its effects were transmitted northwards to affect and reactivate older structures. There was extensive volcanic activity during the Tertiary, and some famous asteroid impact sites. 

Cost £75

tuesday 25th


wednesday 26th

Bristol Nats Lecture
When
Wed, 26 February, 19:30 – 21:00
Where
Room 1.5 Wills Memorial Building, University of Bristol (map)
Description
Trains and Trilobites
Talk by David Clegg
Geological journeys in Canada including the Burgess Shale

thursday 27th

Geostudies Lecture - Uniformitarianism
When
 19:30 – 21:30
Where
The Chantry, Thornbury (map)
Description

The Limits of Uniformitarianism.


The science of geology is heavily dependent on the principle of uniformitarianism – the idea  that geological conditions and processes have remained substantially unchanged through geological time, meaning that we can interpret the past on the basis of our understanding of the geological present. But how accurate is this principle? To what extent were conditions and processes different in the past? Are present conditions and processes typical? How well do we understand present processes? And there are also spatial features to consider; A casual examination of a modern sedimentary or volcanic environment reveals rapid and wide-ranging changes in facies over a small area. Our evidence of past environments is largely based on small, possibly unrepresentative, exposures of tiny fractions of those past environments. Are we justified in using evidence from the past to interpret the present and future, such as climate change?  Held at The Chantry, Thornbury, in the Hanover Room.  First meeting 7.30 – 9.30, Thurs 16th  January until April 2nd  (not Thurs 20th Feb or 19th March). Cost £75


Programme

What do we mean by Uniformitarianism? Origin of the term and the historical context in which it arose and developed as a counter to “Old” Catastrophism.

What are the main problems with Uniformitarianism? The rise of “New” Catastrophism in the later part of the 20th century. Problems of direction, cyclicity, punctuation, gradualism in the following fields of geology:

Uniformitarianism and sedimentation. Have conditions changed over geological time? How representative in terms of coverage and completeness is the sedimentary record?

Uniformitarianism and volcanicity, earthquakes, intrusion and landslides (Mar 13)

Uniformitarianism and the solar system – external processes affecting earth geology (Mar 27)

Uniformitarianism and major environmental change (such as climate and sea level changes) (Mar 5)

Uniformitarianism, evolution and mass extinction (Mar 12)

Uniformitarianism and tectonics – was plate tectonics a relatively young development? Is the Wilson (supercontinent) Cycle real? (Mar 26)

Geomorphology and Uniformitarianism (Apr 2)

Is the present the key to the past? (or in reverse?)

friday 28th


saturday 29th

Bath Geol Soc - Field Trip
When
Sat, 29 February, 10:30 – 12:00
Where
Brown's Folly Car Park (G.R. ST 798663) (map)
Description
Brown's Folly Nature Reserve
Leader: Graham Hickman, Bath Geological Society
The annual, morning clear-up of the Great oolite exposures on the SSSI reserve near Bathford. Bring your secateurs and hedge trimmers to cut back the vegetation and clean up the outcrops, or just take the opportunity to visit the sites and talk about geology.

Meet at 10.30 a.m. at Brown's Folly Car Park (G.R. ST 798663). Strong boots, waterproofs and hard hats are required.

sunday 1st