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Travel log – The Kenya rift

Travel log – The Kenya rift

Topographic map of the Kenya rift and surroundings. Dark red lines indicated faults from the GEM database. Dotted blue lines separate the northern, central and southern Kenya rift. In green circles the discussed locations.

A little over a year ago, I was lucky enough to join a field trip to the Kenya rift organized by Potsdam University and Roma III. This rift is part of the active East African Rift System, which I introduced in a previous blog post. With a group of 25 enthusiastic participants from Roma Tre, Potsdam University, Nairobi University and GFZ Potsdam (we somehow always managed to make the 20-person bus work), we set out to study the interaction between tectonics, magmatism and climate and their link to human and animal evolution. Based on several pictures, I’ll take you through the highlights.

 

 

 

 

Basement foliation and fault orientation

Two numerical modellers looking at rocks… Gneisses of the Mozambique belt with steeply dipping foliation – I think. Courtesy of Corinna Kallich, Potsdam University.

Although this first picture might not look so impressive (I promise, more impressive ones will come), this road outcrop shows the structure of the basement that is responsible for the orientation of the Kenya rift’s three western border faults. Here in particular, we are slightly west of the Elgeyo escarpment, the scarp of the major east-dipping Elgeyo fault. It reactivated the steep foliation of the Mozambique belt gneisses that formed during the Pan-African orogeny (550-500 Ma; Ring 2014). Changes in foliation orientation are mirrored by changes in fault orientation from NNE to NW upon going from the Northern to the Southern Kenya rift (see map). The Elgeyo fault itself displaced the 14.5 My old massive extrusion of phonolite lavas that can be seen throughout the Kenya rift area, marking the start of the current rift phase. From the differences in basement level between the western shoulder and the rift centre, the total offset along the fault is ~4 km!

Rift axis volcanism

Lunch overlooking the Menengai caldera that collapsed 36,000 yr ago. Courtesy of Corinna Kallich, Potsdam University.

With on-going rifting, the tectonic and magmatic activity localised in the centre of the Kenya rift. One massive central volcano is the Menengai volcano, whose view we enjoyed over lunch. This 12 km wide caldera collapsed 36,000 yr ago; the ash flows of the eruption can be found throughout the whole of Kenya. Within the caldera, diatomite layers alternating with trachyte lava flows indicate the presence of lakes 12 and 5 ky ago. These lakes were fed by the neighbouring Nakuru basin overflowing into the Menengai crater. The volcano itself was responsible for the earlier compartmentalization of the larger Nakuru-Elmentaita basin. At the moment, freshwater springs are being fed by the groundwater, and 40 geothermal wells are being constructed to benefit from the groundwater being heated by the magma chamber at 3-3.5 km depth.

Lunch at Hell’s Gate

Looking along Hell’s Gate Gorge – cut into the white diatomite and pyroclastic layers – towards feeder dikes of the remaining core of a volcano. Courtesy of Corinna Kallich, Potsdam University.

Watching the wildlife and beautiful scenery is usually the reason people visit Hell’s Gate National Park, but we studied the flow structures in a highly viscous, silica-rich lava flow. We then scrambled our way through Hell’s Gate Gorge that cut into mostly diatomite lake sediments (these algae are very helpful) alternated with pyroclastic layers. Most impressive however, were the crosscut basaltic intrusions that we could trace back to the centre of an otherwise eroded volcanic dome. The well-deserved lunch was a rather frustrating affair, as Vervet monkeys took every chance at stealing our food, not even shying away from distracting us with their adorable babies.

Monkey enjoying my lunch. Courtesy of Corinna Kallich, Potsdam University.

 

 

 

 

 

Wishing the lake was back

The white diatomites of the Olorgesailie Formation, indicating the presence of a lake. Courtesy of Corinna Kallich, Potsdam University.

The Olorgesailie basin is where paleoanthropologist Louis Leakey and his wife palaeontologist Mary Leakey (Wikipedia) unearthed a score of Acheulean hand axes in the 1940s. The 600-900 ky old tools were used to dig for roots, cleave, hammer and scrape meat and can be seen in the Kariandusi museum site. Besides the hand axes (made from all the trachyte found in the area), we marvelled at the Olorgesailie Formation that contains them, which was deposited between ~1.2-0.5 Ma. The formation consists of repetitions of wetland, river and lake sediments and paleosols (fossil soils, indicating dryer conditions). As we stand baking in the sun on top of the dusty, white diatomite, the vision of a lake sure is very alluring.

A not-so-fresh lake

On our way to a tiny hotspring along the edge of the slightly pink waters of Lake Magadi. In the foreground the white evaporates the lake is mined for. Courtesy of Corinna Kallich, Potsdam University.

While we mostly stayed in resorts, our only campsite (proper “glamping” with a shower and bathroom in the tent) was close to Lake Magadi, one of the lakes along the rift axis. This saline, alkaline lake gave its name to magadiite, a sodium hydro silicate, that when dehydrated forms chert (i.e. flint). The lake is also mined for its sodium carbonate, known as trona. During the African Humid Period (15,000-5,000 yr ago; Maslin et al. 2014), Lake Magadi was about 40 m higher, a lot fresher and connected to Lake Natron further south. Fun fact from Wikipedia: elephants visit the Magadi Basin to fill up on their own salts supplies as well. From my own experience, I can tell you, it does not taste very good.

 

 

My trusted companions for over a decade did not survive Kenya’s heat and volcanics… Serves me right for not taking them out often enough!

And then there were the hippos, neptunic dikes, dancing Maasai, a boat trip to the hydrothermal vents on Ol Kokwe Island, giraffes outside our cabin, midnight stargazing… too much to capture in one blog post. I had a wonderful time in Kenya exploring the geology, admiring the wildlife and getting to know its people. My only regret? Losing my shoes…

 

 

 

 

References:

Maslin, M. A., Brierly, C. M., Milner, A. M., Shultz, S., Trauth, M. H., Wilson, K. E. (2014). East African climate pulses and early human evolution, Quaternary Science Reviews 101, 1-17.

Ring, U. (2014). The East African Rift System, Austrian Journal of Earth Sciences, 107, 1.

Strecker, M. R., Faccenna, C., Wichura, H., Ballato, P., Olaka, L. A. and Riedl, S. (2018). Tectonics, seismicity, magmatic and sedimentary processes of the East African Rift Valley, Kenya, Kenya Field School Field Guide.

Personal communication with Strecker, M. R., Wichura, H., Olaka, L. A. and Riedl, S.

Conferences: Secret PhD Drivers

Conferences: Secret PhD Drivers

Conferences are an integral part of a PhD. They are the forum for spreading the word about the newest science and developing professional relationships. But as a PhD student they are more likely to be a source of palpitations and sweaty palms. This week Kiran Chotalia writes about her personal experience on conferences, and lessons learnt over the years.

Kiran Chotalia. PhD Student at Dept. of Earth Sciences, University College London, UK.

My PhD is a part of the Deep Volatiles Consortium and a bunch of us started on our pursuit of that floppy hat together. Our first conference adventure was an introduction to the consortium at the University of Oxford, where the new students were to present on themselves and their projects for a whole terrifying two minutes. At this stage, we had only been scientists in training for a few weeks and the thought of getting up in front of a room of established experts was scary, to say the least. Lesson #1: If it’s not a little bit scary, is it even worth doing? It means we care and we want to do the best we can. A healthy dose of fear can push us to work harder and polish our skills, making us better presenters. Overcoming the fear of these new situations takes up a lot of your energy. But it always helps to practice. In particular, I’ve always been encouraged to participate in presentation (poster or oral) competitions. Knowing that you’re going to be judged on your work and presentation skills encourages you to prepare. And this preparation has always helped to calm my nerves to the point where I’m now at the stage I can enjoy presenting a poster.

Regular work goals that crop up in other professions are often absent, especially when we’re starting out.  The build-up to a conference acts as a good focus to push for results and some first pass interpretations. At the conference itself, it makes sure people come to see your poster and you can start to get your face out there in your field. Lesson #2: Sign up for presentation competitions. AGU’s Outstanding Student Presentation Award (OSPA) and EGU’s Outstanding Student PICO and Poster (OSPP) awards are well established. At smaller conferences, it’s always worth asking if a competition is taking place as, speaking from experience, they can be easily missed. They also give you a good excuse to practice with your research group in preparation, providing the key component of improving your presentation skills: feedback. Lesson #3: Ask for feedback, not just on your science but your presenting too. If you’re presenting to people not in your field, practice with office mates that have no idea what you get up to. By practicing, you can begin to find your style of presenting and the best way to convey your science.

Me, (awkwardly) presenting my first poster at the Workshop on the Origin of Plate Tectonics, Locarno.

Sometimes, you’ll be going to conferences not only with your fellow PhD students, but also more senior members. They can introduce you to their friends and colleagues, extending your network, more often than not, when you are socialising over dinner, after the main working day. Lesson #4: Keep your ear to the ground. These events provide a great opportunity to let people know you are on the hunt for a job and hear about positions that might be right for you. At AGU 2018, I became the proud owner of a ‘Job Seeker’ badge, provided by the Careers Centre. It acted as a great way to segue from general job chat into potential leads. A memento that I’ll be hanging on to and dusting off for conferences to come!

One of the biggest changes to my conferencing cycle occurred last year after attending two meetings: CIDER and YoungCEED. Both were workshops geared towards learning and research, with CIDER lasting four weeks and YoungCEED lasting a week. Lesson #5: Attend research specific meetings when the opportunity arises. Even if they don’t seem to align with your research interests from the outset, they are incredible learning opportunities and a great way to expand your research horizons. By attending these meetings, the dynamic of my first conference after them shifted. There was a focus on catching up with the collective work started earlier in the year. Whilst the pace was the most exhausting I’ve experienced thus far, it was also the most rewarding.

Between all the learning and networking, faces start to become familiar. Before you know it, these faces become colleagues and colleagues quickly become friends. In our line of work, our friends are spread over continents, moving from institution to institution. They tend to offer the only opportunity to be in the same place at the same time. This also results in completely losing track of time and catching up into the early hours of the morning, so the next lesson is more subjective. Lesson #6: Know your limits. Some can stay out until 4am and rock up at the 8.30am talk. I wish I was one of these people but I have a hard time keeping my eyes open past 12.30am. Whatever works for you!

Me, presenting my most recent poster at AGU 2018 with my job seeker badge!

After the conference finishes, you are often in a place that you’ve never visited before. Lesson #7: Have a break. If you can, even an extra day or two of being a tourist is great treat after a hectic build-up as well as the conference itself. If staying for a mini holiday post-conference is not an option, make sure you take some time when you get home to rest and readjust before you get back to work and start planning for the next one.

Last but not least, Lesson #8: Don’t forget to have fun. The stress surrounding conferences and your PhD in general can at times be all consuming. Remember to enjoy the small victories of finally getting a code to run or finding time on the SEM to analyse your samples. At conferences, enjoy being surrounding scientists that are just starting out and the seasoned professionals with a back catalogue of interesting stories. And if you’re lucky enough to be at a conference somewhere sunny, make sure to get outside during the breaks and free time to soak up some vitamin D!

The Shanghai skyline after the Sino-UK Deep Volatiles Annual Meeting at Nanjing University.

A belated happy new year!

A belated happy new year!

It was that time of the year again: holidays! Time to take a break from work, relax, and see all your friends and family again. The blog team is no different: we took a break from blogging for a little while as well, so you had to survive the holidays without us! Did you survive Christmas day without one of our blogposts? It must’ve been dreadful, I know, but that’s life! Luckily, we have some good news: we are back with some belated happy new year wishes and wintersport recommendations. We also tried to write limericks. Also also, we discuss chocolate and peppermint. Because we can. Cheers to a good blog year in 2019! 

Iris van Zelst

I once tried to ski down a slope
as friends thought there might be hope
I was covered in snow
from my head to my toe
If they invite me again it’s a ‘nope’

So, as many of you might have guessed, winter sports (or any sports, really) are not entirely my thing. Particularly skiing did not go down well for me. However, as a true Dutch girl, I do really enjoy ice skating and can recommend it thoroughly! However, this year no winter sports at all for me: I flew towards the sun in an effort to actually destress from work (feeble attempt as I brought my laptop, but still, kudos for trying, right?). I hope everyone had a very nice holiday and relaxing break. May all your (academic) wishes come true in 2019!

I also tried cross-country skiing once. That was infinitely better than alpine skiing. It was actually fun!

Grace Shephard

In hemispheric defiance of the “wintersport” edition, I am currently back Down Under where I have replaced the (seemingly eternal) television coverage of cross-country skiing with cricket, swapped a toboggan for me ‘togs’, and exchanged a pull-over for some ‘pluggers.’ I wish all of our blog readers a very happy and safe end to the year that was, and a fabulous start to the next!

What Aussies call swimming-related attire from bit.ly/AusWords

Anne Glerum

This year I spend winter in Berlin,
Where no snow has fallen and the ice is too thin.
So I drink myself heavy,
With hot chocolate and Pfeffi,
And wait for the fresh air of spring!

In the weeks before Christmas, Christmas markets dominate the streets of Berlin. Besides delicious food, they offer mulled wine and, as I discovered this year, hot chocolate with peppermintliqueur. A green version of the liqueur is made by Pfeffi, while a colorless Berlin-made peppermintliqueur is called Berliner Luft. It’s as clear and fresh as Berlin’s air according to the manufacturer. Although the freshness of Berlin’s air is debatable, the combination of chocolate and peppermint is delicious. I wish everybody a fresh start of the New Year with loads of hapiness!

Get conference ready!

Get conference ready!

It’s almost time for the AGU fall meeting 2018! Are you ready? Have you prepared your schedule and set up all your important business meetings? Here are some final tips to nail your presentation and/or poster!

Nailing your presentation
The art of the 15-minute talk: how to design the best 15-minute talk
Presentation skills – 1. Voice: how to get the most out of your presentation voice
Presentation skills – 2. Speech: how to stop staying ‘uh’

Making the best poster
Poster presentation tips: how to design the best poster layout
The rainbow colour map (repeatedly) considered harmful: how to make the best scientific figures