Tolbachik is a basaltic volcanic massif lying at the southern end of the Kliuchevskoi group in Kamchatka, Russia. It comprises two overlapping cones: Plosky Tolbachik, a Holocene shield volcano extending to 3 km in diameter; and the older (Pleistocene) Ostry Tolbachik, a sharp-topped stratovolcano reaching some 3,700 m in height.
Science Snap (#21): Diatoms
KT Cooper is a PhD student in the School of Earth Sciences at the University of Bristol. A carbonate geochemist by training, she has just returned from a three-month secondment to Houston, Texas, USA working with Exxon Mobil.
When you start looking at things at a microscopic level, everything starts to look a little alien. Minerals assemblages can look like the landscapes of far off planets and microbes can look like their inhabitants. One such type of alien looking microscopic life form are diatoms.
Diatoms are type of algae and their colonies generate the strangest of shapes; think of them as nature’s 3D spirographs. Their cell walls are composed of silica and they can be found in many aquatic environments, from the oceans to freshwaters. Diatoms can be used to inform scientists about the environment in which they grew and how this may have been altered due to climate change. But for me, it’s just interesting to see the huge variability in their morphology.
Beyond a rock…
It’s not often on BaR that we feature a personal blog, but I can’t live a lie any longer. I am officially Beyond a Rock.
Science Snap #21: Nash Point, Vale of Glamorgan, Wales
Sorcha McMahon is a third year PhD student in the School of Earth Sciences at the University of Bristol. Sorcha is investigating how strange igneous rocks called carbonatites may have formed, using both natural samples and high-pressure experiments.
Nash Point is a picturesque headland along the coastline of the Vale of Glamorgan, consisting of near-vertical cliffs of limestone and mudstone. Strata are of Blue Lias age, and at low tide the exposed shore platform reveals indicative fossils including tiny ammonites.
Local towns of St. Donats or Llantwit Major are convenient bases for the short walk along the coastline, and the walk covers part of the impressive Glamorgan Heritage Coast path. The site itself can be accessed from the cliff tops, and is a short distance from Nash Point lighthouse. This was the last manned lighthouse in Wales (it became automated in 1998), and is now open to the public.