Popocatépetl: a song of snow and fire | Volcanology

Dear reader, be aware… the content of this blog may be explosive! As I am writing this, the crater of the Mexican volcano, Popocatépetl, is alight with the glow of the hot lava that is slowly being squeezed out to the surface. Sometimes this happens very calmly, and only a trail of puffs of steam mark the activity.

Smoking Popocatepetl
Smoking Popocatépetl, 24 Jan 2016. © José Arnoldo Rodríguez Carrington via Flickr

But this apparent tranquility can quickly change into something much larger, much more violent, and much more dangerous to the 30 million people living around Popocatépetl. How can the volcano change its behavior so quickly? And what, exactly, does quick even mean in this case? Well, this is what we Volcanologists at the Museum are trying to find out, and that is why we are right now packing our geological hammers, getting ready to take off to Mexico!

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How do you scan a shark? | Vertebrates Palaeobiology

You may have seen the Museum’s work in the news recently, when our scan of a catshark helped University of Sheffield researchers understand how shark teeth evolved. In this blog, Brett Clark from the Museum’s Vertebrates Palaeobiology department shows us the method used.

Our research, led by Dr Zerina Johanson, investigates the evolution and development of teeth in jawed vertebrates – in particular, the tooth arrangement of present day sharks.

But how exactly do you scan a shark?

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Notes in the collections tell natural stories | Curator of Micropalaeontology

Earlier in the summer I tweeted a picture of a microfossil slide I made in 1997. On the back I had written that it was made while I was listening to England bowl Australia out for 118 in a cricket test match at Edgbaston, Birmingham.

slide with cricket annotation
A microfossil slide with a cricket-related annotation on the back.

The slide got me thinking about more important hidden notes I have found recently that relate to historical events and provide a context to the microfossil collection. This post examines evidence of a collector’s escape from a disintegrating ice floe, attempts to cover-up a major disagreement between two scientists and the sad end for a laboratory that led to my first job as a curator.

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Chance discovery contributes to origins and evolution focus | Curator of Micropalaeontology

When I first came to the Museum I dreamt that one day someone would bring something in for identification that I would recognise to be a really important find. The contents of a consultancy sample back in 2005 helped to make my wish come true. This post tells of the discovery and subsequent publication of a significant species of early fossil fish from Oman that provides information on the origins and evolution of life on our planet, one of the main focus areas of Museum science.

Montage of photos showing close ups of fossil plates and scales
Examples of plates and scales of the early fish Sacabambaspis

Very occasionally I get consultancy rock samples sent to me for dissolving to find microfossils. This is so that we can provide the age for a rock formation or details about fossil environments or climate. And so it was that Alan Heward, then of Petroleum Development Oman (PDO), sent me a sample in 2005 for analysis to try to find age diagnostic conodonts. Conodonts are extinct phosphatic microfossils that look like teeth and are used extensively for dating rocks that are roughly 500-205 million years old.

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New paper: Modal mineralogy of CI and CI-like chondrites by X-ray diffraction | Meteorites

Some meteorites, called CI chondrites, contain quite a lot of water; more than 15% of their total weight. Scientists have suggested that impacts by meteorites like these could have delivered water to the early Earth. The water in CI chondrites is locked up in minerals produced by aqueous alteration processes on the meteorite’s parent asteroid, billions of years ago. It has been very hard to study these minerals due to their small size, but new work carried out by the Meteorite Group at the Natural History Museum has been able to quantify the abundance of these minerals.

A CI chondrite being analysed by XRD. For analysis a small chip of a meteorite is powdered before being packed into a sample holder. In the image, the meteorite sample is the slightly grey region within the black sample holder. The X-rays come in from the tube at the right hand side.
A CI chondrite being analysed by XRD. For analysis a small chip of a meteorite is powdered before being packed into a sample holder. In the image, the meteorite sample is the slightly grey region within the black sample holder. The X-rays come in from the tube at the right hand side.

The minerals produced by aqueous alteration (including phyllosilicates, carbonates, sulphides and oxides) are typically less than one micron in size (the width of a human hair is around 100 microns!). They are very important, despite their small size, because they are major carriers of water in meteorites. We need to know how much of a meteorite is made of these minerals in order to fully understand fundamental things such as the physical and chemical conditions of aqueous alteration, and what the original starting mineralogy of asteroids was like.

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A new microfossil display at the Museum | Curator of Micropalaeontology

Last month a new temporary display featuring some of our foraminiferal specimens and models was placed in the Museum gallery. This features real microfossils on one of our foraminiferal Christmas card slides alongside 20 scale models, part of a set of 120 models generously donated to us last year by Chinese scientist Zheng Shouyi.

Senior Microfossil Curator Steve Stukins admiring some of the specimens and models on display and thinking
Senior Microfossil Curator Steve Stukins admiring some of the specimens and models on display and thinking “this is a much better place for them than the Curator of Micropalaeontology’s office!”

As a curator dealing with items generally a millimetre or less in size I have not often been involved in developing exhibits other than to provide images or scale models like the Blaschka glass models of radiolarians. Displaying magnified models is one of the best ways to show the relevance of some of the smallest specimens in the Museum collection, the beauty and composition of foraminifera and to highlight our unseen collections.

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