Geology: the foundation of #Civilizations, Petra @McrMuseum

One of my highlights from the first episode of the stunning new BBC Civilizations series (available on BBC iPlayer) was Simon Schama’s visit to Petra.

Image Wikipedia Berthold Werner

This beautiful building, created during the 4th century Nabataean Kingdom was only possible because of the  the properties of the sandstone it is carved into.

Most buildings are made from rock that has been excavated, shaped into blocks which are then stacked to make walls. Petra is different, the columns, doors and rooms have all been excavated from the bedrock in the side of the gorge.

The Nubian Sandstone

The orange-brown sandstone at Petra was formed over a range of different time periods (from the Cambrian to the Upper Cretaceous) and was formed in a variety of different conditions from desert to shallow seas. The distinctive colour comes from the iron minerals that have reacted with oxygen forming the rusty-red.

Sand from Petra

The sandstone is very similar to the Triassic sandstone found in Cheshire and north-west England. This formed during desert conditions. The remains of the sand dunes can still be seen where the rock is exposed at the Stockport railway viaduct (on the M60) and the railway cutting going into Liverpool Limestreet station.

Triassic desert sandstone from Cheshire, similar to the sandstone at Petra

So what made it possible to create this building at Petra?

Not too hard, not too soft

Like the story of the Three Bears and the porridge, the sandstone here is just right. The strength and hardness come from how strong the cement is that holds the grains together to form the rock.

Too soft and it crumbles into sand. Softer parts of this sandstone have eroded away over the years and now form much of the sand of the Arabian Desert. Too hard and it is difficult to chisel out to form features (such as the details at the top of the columns) and rooms.

Strength

In contrast to buildings made from blocks of rock, Petra is pretty strong when under attack from armies, earthquakes and the ravages of time. Conventional block built buildings inevitably have points of weakness where the blocks meet.

It looks nice

One of the marks of culture and civilization is the desire to be surrounded by beautiful things. I guess it is a matter of personal taste, but the sandstone is a beautiful rusty-red colour reflecting the iron-minerals coating the quartz grains in the sandstone.

Right place at the right time

Petra was on a key trading route. It sits in a narrow sheltered gorge with little room for conventional buildings. The obvious thing to do is tunnel into the soft rock.

I didn’t want to miss an excuse to include a clip of one of my favorite films: Indiana Jones And The Last Crusade. Good opportunity to look at the Nubian Sandstone 🙂

Lamp from Petra, Manchester Museum

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Marie Stopes re-assessed: reluctant Mancunian, sexual revolutionary, birth control pioneer

Our very own Honorary Researcher Dr. Clare Debenham will be giving a talk about the life and impact of Marie Stopes at Manchester Museum on:

Saturday 10th of March 2018, book your ticket on Eventbrite!

Marie Stopes studying plant fossils now in Manchester Museum
Image courtesy of John Rylands Library

Marie was controversial in her lifetime, but since the Second World she has been maligned both in the academic world and in the popular press. Now is the time to re-assess her achievements. This talk offers a frank appraisal. 

Marie Stopes was the first female lecturer at the University of Manchester and worked on the Museum’s fossil plant collection. Her book, Married Love was published 100 years ago and became an immediate best seller as capturing the mood of the age. The enthusiastic response to Married Love encouraged Marie to set up the country’s first birth control clinic. 

This will be a rare opportunity to see the fossils collected by Marie Stopes and hear about her fossil collecting adventures.

Love Fossils? – We need your help!

 

If you love fossils and want to help us unlock the treasures of Manchester Museum’s fossil collection, this is your chance to make a real difference. This Valentine’s day, we are inviting people to unlock the treasures at the heart of the museum through our exciting new online project Reading Nature’s Library.

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Reading Nature’s Library has been developed to reveal information about the museum’s amazing objects to help discover more about our world. The project is part of Zooniverse an online home for interesting projects looking for volunteer help. With over 4.5 million objects in the museum’s collection, recording this information is too great a task for us to tackle alone. The first few thousand objects have been photographed and we want your help to read the labels and record the names, places and other information.

 

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Gneiss new to the collection from beautiful Bhutan #MMCourtyard

We have a new rock in the collection which will help us tell the story of the formation of the Himalayan mountain chain. We are currently developing activities and displays for our Courtyard Project which will include our South Asia Gallery in partnership with the British Museum.

Byron Adams and Frances Cooper  very kindly collected the rock for us on a recent trip to Bumthang, Bhutan where they have been studying the interactions between tectonics climate and surface processes. This is our first rock from Bhutan and it is a stunningly beautiful part of the world.

Bumthang (which means ‘Beautiful field’), Bhutan 2912m above sea level. Image taken by Byron Adams.

The rock is an example of Augen Gneiss (Augen from the German for ‘eyes’) which forms  in extremely high pressure and temperature environments during mountain building. The Augen are the lens-shaped white Plagioclase Feldspar crystals seen in image below.

White lens-shaped augen of Plagioclase Feldspar crystals in layers of black mica

This rock joins our recent acquisition of a piece of Mount Everest piecing together story of the geological history of the region.

Reaching new heights with collecting: Everest specimen

I’m excited to say we have reached new heights with our collection: we’ve acquired a rock fragment from Mount Everest!

The fragment was donated by Nobel Prize winner Professor Andre Geim, who was given it by David Tait MBE, who has climbed Everest five times raising money for the NSPCC.

Mount Everest from the south
By Anju Sherpa (Own work) [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)%5D, via Wikimedia Commons

I think I’d be the first to admit that it is not the most spectacular looking specimen in the collection, but it definitely trumps everything on location and effort put in to collecting it. I’ve been in touch with David Tait to thanks him and ask about where it was collected. He said that it was from the ‘upper reaches’ of Mount Everest and he apologised for it being quite small!

The geology of Mount Everest is quite interesting and as our rock is a Schist rather than the Ordovician Limestone, it can’t quite be from the very top.

The best paper I’ve found is: SEARLE, M., SIMPSON, R., LAW, R., PARRISH, R., & WATERS, D. (2003). The structural geometry, metamorphic and magmatic evolution of the Everest massif, High Himalaya of Nepal-South Tibet Journal of the Geological Society, 160 (3), 345-366  DOI: 10.1144/0016-764902-126

We are currently developing activities and displays for our Courtyard Project which will include our South Asia Gallery in partnership with the British Museum. So a piece of Mount Everest will be a fantastic way of helping tell the story of the geological history of the region.

Gold!

Christmas at Manchester Museum

goldGold in quartzite. Geology Collection, Manchester Museum.

Gold – A Gift for a King

A Christian association with gold is the gift the three kings gave to Jesus in recognition of his kingship –

“and going into the house they saw the child with Mary his mother, and they fell down and worshipped him. Then, opening their treasures, they offered him gifts, gold and frankincense and myrrh.” (Matthew 2:1–2, 11).

the-three-wise-kings-atlas-catalan-1375-fol-v-980x498.pngThe Three Wise Kings – detail from the Catalan Atlas, 1375. Image from springfieldmuseums.org.

Gold is universally considered one of the great earthly treasures and an appropriate gift for rulers throughout history due to its rarity and purity.  The chieftains of pre-Colombian America interpreted its dazzling yellow colour as enchanted with protective powers captured from the sun god, wrought armour from the soft malleable stuff, which of course proved deceptive in battle.  Heavenly associations with gold are repeated…

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Marie Stopes: Social Reformer, Palaeobotanist and… Artist

Guest blog by Clare Debenham, Honorary Researcher at Manchester Museum

Marie Stopes was the first woman science lecturer at what is now the University of Manchester. She went on to be controversially a sexual revolutionary and birth control pioneer.

What is not widely known is that she was also a talented artist. This illustration of a Cycad comes from her book:

Cycad illustration from Ancient Plants, Marie Stopes 1910

We’ve recently discovered this unsigned water colour, found in the Botany collection at Manchester Museum, which may also be her work.

Cycad painting possibly by Marie Stopes. It shows some differences from her illustration above, but dates from the time Marie Stopes was working at Manchester University.

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