About me:
Hi! I’m Rehemat, I’m 23 and from south London. I did my undergraduate degree in Geoscience at Royal Holloway (Uni. of London) and graduated last summer. I’m currently at UCL studying for a PhD and am in my first year.
I also play the violin and am part of two orchestras, and enjoy surfing, snowboarding (although I haven’t been for a few years), and more recently – rock climbing!

My work:

Plankton are microscopic organisms which float around the ocean and cannot swim against a current. There are two types – zooplankton (animals with one cell) and phytoplankton (plants). Foraminifera (forams for short) are zooplankton with a body (shell, also called a test) made from calcium carbonate (calcite) – thats the same material as the white stuff you can find in your kettle. They have one cell and come in many different shapes and sizes, and have different living habits too. Planktonic forams float in the uppermost part of the ocean (top 500 metres) and benthic forams live on the ocean floor. There are also larger benthic forams – the best and probably the most impressive place to find one species of these (Nummulites) are in the pyramids in Egypt – each building block contains thousands of Nummulites! Forams eat lots of things including phytoplankton, copepods (like shrimp) and bacteria. Some forams even build their bodies out of any material which surrounds them. They’re called agglutinated forams.
I study fossilised planktonic forams from a time period known as the Eocene (56 – 33.9 million years ago). During the Eocene there was lots of carbon dioxide and global temperatures were much higher than they are today. Scientists use the Eocene as a parallel to what our climate could be like by 2100. Although the Eocene is characterised by a gradual cooling, but had periods of extreme warmth called hyperthermals. These include the Palaeocene-Eocene-Thermal-Maximum (55.7 million years ago, the Palaeocene is the time period before the Eocene) and the Middle Eocene Climatic Optimum (40 million years ago). There’s also one called Eocene Thermal Maximum, also known as the ELMO event – the scientists who discovered the event found a change in a *red* carbonate poor clay rich horizon. Its good to know climate scientists have a sense of humour too!!!
Foram test chemistry can be used to work out lots of different things including depth habitats (so if the forams lived in surface water or deeper in the ocean), whether they had symbionts (like algae) and past sea surface temperatures (using the ratio of magnesium to calcium and putting this into a mathematical equation). Just like animals in their natural environments, forams respond to different environmental conditions (vital effects) in the ocean. However we can’t actually work out exactly what they did in the ocean and we don’t know exactly how different elements ‘fit’ into the crystal structure of foram calcium carbonate either. So really all past climate chemistry data from foraminifera has to be questioned in terms of this! Part of my work will be looking at this problem and working out exactly how accurate the data we get from forams are.

I normally start the day by checking my emails and reading any papers that have been published recently – I get alerts through to my email every time a new publication/journal issue released and personally I find it easier to just read them when I get the email otherwise sometimes I forget! Next, I normally make a list of the things I have to do and then start on that.

Right now, I have a set of 52 samples which are between 54.4 and 38 million years old from a time period known as the Eocene. Each sample has to be washed down and sieved in order to turn them from a hard block of sediment into sand sized grains, so I can work with them. In every sample I’ve got to identify which foraminifera species are present. So first, I empty some of the material into a small black dish which has a grid on it. Then I use a  technique called foraminifera picking. This involves using a paintbrush (and some water to wet the bristles of the paintbrush so the forams will stick to them) and then literally picking a foram from the picking tray into a slide. Its a very careful and slow process and its really important to have a steady hand and hope your forams don’t ‘jump’ out of your picking tray if they don’t stick to the bristles. There are so many different foram species and sometimes it is quite hard to tell them apart, especially if they look very similar! Using a scanning electron microscope is very useful, and can help to identify different species and look more carefully at the appearance of a foram too.

As my project is partly geochemical based, I will also be doing some chemistry on my forams and putting them into different  machines called mass spectrometers to find out the amounts of different elements in their skeletons. The preparation techniques for every type of mass spectrometry analysis are different:

For solution ICP-MS analysis (where I’ll need to use at least 30 forams per sample) the preparation is much longer and involves a lot more steps and lots of different chemicals like nitric acid and hydrazine; forams also have to be crushed using two glass plates – you have to place them on one glass plate, line them up then slowly place the other glass plate on top so you can crush them.

For LA-ICPMS analysis (where I’ll be analysing about 10 forams per sample) the preparation is much simpler. The forams need to be cleaned in deionised water in a test tube. The water is replaced in the test tube 4 times, and after the 4th time the test tube with the forams in is placed in an ultrasonic bath which shakes the water very fast for about 5-10 seconds (or less depending on how fragile the forams are) in order to make any clay particles fall off the forams. Sometimes scientists use a water-methanol mix for this step.

I did some LA-ICPMS analysis in early May:  This picture shows a bit of what I did!

Glossary

ICP-MS: Inductively Coupled Plasma Mass Spectrometry
LA-ICPMS: Laser Ablation Inductively Coupled Plasma Mass Spectrometry

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What I’ll be up to during “I’m a geoscientist get me out of here!”

One of the perks of working within the world of research and science is you get to travel. So from June 3rd-8th and 17th-22nd I’ll be at a summer school in Urbino, Italy. The summer school is all about foraminifera, and is mostly focused on learning about foraminiferal biology and ecology, how they can be used for past environment (palaeoenvironmental) and past ocean condition (palaeoceanographic) interpretations. There are four parts to the summer school (an intro to forams, larger benthic forams, benthic forams and planktonic forams), and I’ll be taking the foram intro and planktonic foram classes. I’m really looking forward to learning more about forams and everything I learn at the summer school will definitely help me when I get back to England and start doing my PhD work again!

MAJOR apologies if you don’t get an instant reply from me during those dates I *promise* to get back to you on the same day and I’m definitely going to be uploading pictures of what I’ll be up to!!

I’m also going back to Italy in early July to present a poster at a conference – if anyone wants to have a look at it I’d be more than happy to send it to you 🙂