Down to Earth Extra January 2023

The January 2023 edition of Down to Earth Extra has been published. You can dowload it from HERE or you can read it below.

Glaciers Have Been Around for 60 Million Years

THIS ARTICLE tells us that glaciers have been around for far longer than was previously thought. It was assumed that the first glaciers of the current ice-house phase appeared after the dramatic cooling which happened 34 million years ago.

But by studying glacial landforms in the Transantarctic Mountains, especially cirques or corries, the authors come to the conclusion that mountain glaciers existed there for the past 60 million years.

At the time Antarctica was covered by dense sub-tropical forests.

ONLINE COURSES FOR JANUARY & FEBRUARY

Nick Chidlaw has asked me to publicise the following courses. We are, of course, pleased to do so - it is the main reason the blog exists!

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During the lockdowns of recent years, I developed and ran a number of online courses on various geological subjects (both located in the UK as well as places abroad). The idea was to offer geological learning to those who usually attend the courses (indoor and outdoor) and field trips I offer, but who were prevented from doing so because of covid-related social restrictions. I was gratified to find so many people enrolled on these courses, and I understand they enjoyed them and gained a lot of new knowledge.  

Although we can now mix much more freely again, the winter months (particularly January and February) are usually a time when doing geological events is restricted by short days and the likelihood of poor weather. Field based events are particularly affected, but indoor events can be also, if snow or ice restricts travelling to and from venues. 

It may be that more of those who enjoy studying geology in the warmer, lighter months would be interested during January and February in doing online courses that enable them to study subjects in their own homes and in periods of time when convenient to them.  A detailed, illustrated course document  is emailed (PDF form) to each enrollee for them to download onto their pcs. These courses 'simulate' an indoor slide-based lecture course. This involves reading through the document in stages as and when convenient to each enrollee, during a set 'Reading Period' of time (scale of weeks). An optional reading list is provided, should enrollees wish to read around the subject further. At the end of the Reading Period, the simulation continues with a 1 week optional 'Dialogue Period' in which all enrollees can send to the tutor if they wish to any questions regarding the course material and which I will answer. A concluding email is then sent to all those enrolled on the course, in which questions and answers are shown that I consider the most beneficial to the learning of the group as a whole.   

I am offering to run 2 such online or 'Distance Learning' courses, one in January, and one in February of 2023. They are independent of one another - you can enrol on either, or both. Please find outline information below. Any queries, email me at nickchidlaw@gmail.com.  I hope you find these proposals interesting and decide to enrol. 

COLD DESERTS OF THE PAST 

Tutor: Dr Nick Chidlaw 

The Quaternary Period extends from 2.6 million years ago to the present, during which time the earth has experienced extensive ice sheets developing episodically in the mid-latitudes. This course focuses on 2 such occasions when glaciations developed in Britain, and looks at sedimentary deposits created in the area of the Cotswold Hills in the west of England. The first is from the 'Anglian Glaciation' over 400,000 year ago, when ice extended down the Vale of Moreton depositing glacial till and outwash gravels. The second is the 'Devensian Glaciation' (less than 100,000 years ago) when meltwater sands and gravels were laid down in the Cirencester area under a cold, tundra climate.

 Coln Gravel Pit near Fairford, Glos.  October 1995. These workings are now flooded to form a lake used for watersports.    

Reading Period  (3 weeks) Monday 2nd - Sunday 22nd January 2023. 

Dialogue Period  (1 week) Monday 23rd - Sunday 29th January 2023

Tuition Fee: £30.00 per person.  No prior knowledge of geology or the study area is assumed. The course document would be sent out to enrollees just before the Reading Period starts. 

In view of postal delivery problems, fees are most conveniently sent by bank trans. I can provide details to those enrolling. 

Course viability deadline Friday 30th December. Fees received will be reimbursed soon after if the course does not reach viability by this date.  

THE FORMER WYE GLACIER FRONT AT HEREFORD 

Tutor: Dr Nick Chidlaw 

Some 26,000 year ago, much of northern and western Britain lay below continuous glacier ice, and adjacent lands were occupied by inhospitable tundra. The Wye Valley Glacier, over 200 m thick, reached as far east as Hereford, where local hills protruded island-like above the ice sheet. This course offers an opportunity to study the legacy of this glacier, some 40 miles from Bristol created during the Devensian, the most-recent glaciation of the Quaternary period. Highlights include the plugging of the pre-glacial valley of the river causing its re-direction to that seen today, and the pond-studded 'kettle-kame moraine' deformed during the melting of contained ice.    

Hereford Pit, a few miles west of the city, in October 1996. Glacial outwash gravels. The Pit is now backfilled and re-landscaped.  

 

Reading Period    (3 weeks)  Monday 30th January - Sunday 19th February 2023. 

Dialogue Period (1 week)  Monday 20th - Sunday 26th February 2023. 

Tuition Fee: £30.00 per person.  No prior knowledge of geology or the study area is assumed. The course document would be sent out to enrollees just before the Reading Period starts. 

In view of postal delivery problems, fees are most conveniently sent by bank trans. I can provide details to those enrolling. 

 Course viability deadline Friday 27th January. Fees received will be reimbursed soon after if the course does not reach viability by this date.  

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New palaeontology online short course from the Natural History Museum

You may be interested in this course from the Natural History Museum. You can find full details HERE.

• Location: Online
  
  
• When: 16 January - 24 February 2023
  
  
• Adult: £149

• Members: £127
  
  
  

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An NHM Masterclass short course

Life on Earth has an intricate history of origins, adaptations, radiations and extinctions but with every new discovery our understanding of the evolution of life becomes clearer. Join a team of Museum researchers and curators as they highlight six moments in the 500-million-year evolutionary history of complex life on Earth, from the beginnings of animal life itself, through the greening of the planet, all the way to the evolution of modern mammals and their subsequent diversification even back to the water whence all life arose.

This course will be delivered online. Each week, a pre-recorded lecture developed specifically for this Masterclass will be released ahead of two live, moderated, interactive Q&A sessions later in the week. The Q&A sessions will be recorded for those unable to attend live, and a reception event will be held for all enrolled students in the last week of the course, for students to meet their peers and the course lecturers at the Museum.

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 Does Evolution Have Favourite Forms - YES!

A correspondent brought THIS ARTICLE to my notice, pointing out that Simon Conway Morris had written about the same thing in 2004 - see HERE. Very true but it does bear repeating. Evolution tends to give the same solution to similar problems even when it is starting from a greatly different source.

The main example the author uses is the crab. Apparently there are five different sorts of crabs alive in the world today. They all look rather similar but, although they are all decapods they are, otherwise, not related.

Crabs are not the only group discussed. The author mentions mammals. There are two major groups - marsupials (with pouches) and placentals which includes you and me. Very different biology but each group has a version of moles, mice, anteaters, gliders, cats and wolves.

Wolf skulls. The marsupial on the left and the placental on the right. The similarity is unmistakable.

The author goes on to discuss similar organs such as eyes. And speculates that alien intelligences may not look all that different from us. Neither the author or I think they are already among us!

1 Day Field Course with Nick Chidlaw

Nick wanted to run this course in early October; there were enough people who wanted to go on the course but there was difficulty with the date. So he is going to run the course on Sunday the 5th March. Nick has contacted the people who expressed an interest in the October date, but if you want to join, I am sure Nick can find a place for you. All you need to know is in Nicks advertisement which is below.

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  A CIRCULAR WALK IN SOUTH GLOUCESTERSHIRE: shallow tropical seas and rivers, ice age valley incision 

Sunday 5th March 2023   10.00 am - 5.00 pm

The generally low-lying landform of much of the county of South Gloucestershire is interrupted near the village of Cromhall by a steep sided, narrow meandering valley lined by rocky crags. The base of the valley was dammed in the 19th century to form a 700m+ long lake, part of the grounds of Tortworth Court (now a hotel). Some 40m deep, the valley is short: indistinguishable from the surrounding countryside only 2 miles to the south of the lake, and likewise so in the open ground on the lake’s north-west side. The stream that feeds and exits the lake is small, and is a ‘misfit’, occupying a valley cut by much more powerful waters during the ice age. Rock exposures, including the natural crags, track cuttings and old quarry workings provide an opportunity to examine the local character of successive stratigraphic units of the Carboniferous Limestone Supergroup. The strata dip 20 – 30 degrees to the south and south east, demonstrating the structural contrast between that found north and south of the ‘Variscan Front’ in the Bristol area, established by the end of the Carboniferous period some 300 Ma. No previous knowledge of geology or the area will be assumed.   

 

A handout outlining the day’s programme, including location sketch map, geological map and cross section, 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.

*     There will be no requirement to wear hard hats on this course. 

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 6th January. If the course has become viable (minimum of 10 enrolments) by this date, enrolments will be able to continue until 1 week (Sunday 26th February) before the course runs..   

Google Earth oblique image of the study area, looking south showing the abruptly-incised meandering valley and lake near the village of Cromhall. 

Track cutting in the Cromhall Sandstone Formation (Middle part). The character of the Carboniferous Limestone Supergroup changes notably between South Gloucestershire and the Mendips; in this area in the north, reddish quartz sandstones and mudrocks, deposited in rivers, occupy much of its upper part and are virtually absent in the south.